explanation blue bibcodes open ADS page with paths to full text
Author name code: madsen
ADS astronomy entries on 2022-09-14
author:"Madsen, Chad Allen"
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Title: The Airborne Infrared Spectrometer: Development,
Characterization, and the 2017 August 21 Eclipse Observation
Authors: Samra, Jenna E.; Marquez, Vanessa; Cheimets, Peter; DeLuca,
Edward E.; Golub, Leon; Hannigan, James W.; Madsen, Chad A.; Vira,
Alisha; Adams, Arn
2022AJ....164...39S Altcode: 2021arXiv210509419S
On 2017 August 21, the Airborne Infrared Spectrometer (AIR-Spec)
observed the total solar eclipse at an altitude of 14 km from aboard the
NSF/NCAR Gulfstream V research aircraft. The instrument successfully
observed the five coronal emission lines that it was designed to
measure: Si X 1.431 μm, S XI 1.921 μm, Fe IX 2.853 μm, Mg VIII
3.028 μm, and Si IX 3.935 μm. Characterizing these magnetically
sensitive emission lines is an important first step in designing
future instruments to monitor the coronal magnetic field, which
drives space weather events, as well as coronal heating, structure,
and dynamics. The AIR-Spec instrument includes an image stabilization
system, feed telescope, grating spectrometer, and slit-jaw imager. This
paper details the instrument design, optical alignment method, image
processing, and data calibration approach. The eclipse observations
are described and the available data are summarized.
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Title: New Observations of the IR Emission Corona from the 2019 July
2 Eclipse Flight of the Airborne Infrared Spectrometer
Authors: Samra, Jenna E.; Madsen, Chad A.; Cheimets, Peter; DeLuca,
Edward E.; Golub, Leon; Marquez, Vanessa; Reyes, Naylynn Tañón
2022ApJ...933...82S Altcode: 2021arXiv210608760S
The Airborne Infrared Spectrometer (AIR-Spec) was commissioned during
the 2017 total solar eclipse, when it observed five infrared coronal
emission lines from a Gulfstream V research jet owned by the National
Science Foundation and operated by the National Center for Atmospheric
Research. The second AIR-Spec research flight took place during the
2019 July 2 total solar eclipse across the south Pacific. The 2019
eclipse flight resulted in seven minutes of observations, during
which the instrument measured all four of its target emission lines:
S XI 1.393 μm, Si X 1.431 μm, S XI 1.921 μm, and Fe IX 2.853
μm. The 1.393 μm S XI line was detected for the first time, and
probable first detections were made of Si XI 1.934 μm and Fe X 1.947
μm. The 2017 AIR-Spec detection of Fe IX was confirmed and the first
observations were made of the Fe IX line intensity as a function of
solar radius. Telluric absorption features were used to calibrate the
wavelength mapping, instrumental broadening, and throughput of the
instrument. AIR-Spec underwent significant upgrades in preparation for
the 2019 eclipse observation. The thermal background was reduced by a
factor of 30, providing a 5.5× improvement in signal-to-noise ratio,
and the postprocessed pointing stability was improved by a factor of 5
to <10″ rms. In addition, two imaging artifacts were identified
and resolved, improving the spectral resolution and making the 2019
data easier to interpret.
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Title: Exploring the middle corona: new instrumentation to address
science questions critical to understanding the thermal structure
and dynamic evolution of the middle corona
Authors: DeLuca, Edward; Winebarger, Amy; Reeves, Katharine; Golub,
Leon; Samra, Jenna; Madsen, Chad; Rivera, Yeimy; Karna, Nishu;
Savage, Sabrina; Seaton, Daniel; West, Matthew; Downs, Cooper; Del
Zanna, Giulio
2021AGUFMSH25F2150D Altcode:
The global structure of the largely unexplored middle corona determines
the physical properties of the inner heliosphere, affects the formation
and acceleration of the solar wind, and controls the dynamics of
eruptive events. Tracing the short and long term global evolution
of the extended corona, identifying changes in corona/heliosphere
connectivity and following the dynamic evolution of eruptive events
in this unexplored region will provide observational data that will
clarify how the corona transitions from closed to open, illuminate the
genesis of coronal mass ejections, and provide input for the design
of the next generation of physics based space weather forecasts. This
poster outlines several critical science questions and identifies the
measurements that are required to make substantial progress towards
addressing the questions. We review and discuss the instrumentation
necessary to capture the observations needed for meaningful progress
in this area as well as the role of simulations in the interpretation
of the observations.
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Title: Probing the Lower Solar Chromosphere Via Dynamical Signatures
of UV Bursts in Cold Lines
Authors: Chaparro, Victoria; Madsen, Chad; DeLuca, Edward
2021AGUFMSH45B2368C Altcode:
UV Bursts are small scale brightenings identified by dramatic
intensification and broadening of emission lines often accompanied
by absorption features from cold metallic ions. They can be used
as probes of plasma conditions in the lower solar atmosphere since
their spectral features suggest they are magnetic reconnection
events in the cool lower chromosphere. We present a spatial and
temporal analysis of the intensification and broadening of the Si IV
1393.78 Å and Cl I 1351.66 Å lines observed by the Interface Region
Imaging Spectrograph (IRIS) to trace magnetic reconnection outflows
through the lower chromosphere. We employ a semi-automated UV burst
detection algorithm by applying single-Gaussian fits (SGF) to the Si
IV 1394 Å line in IRIS sit-and-stare data. We first isolate the likely
candidate population in the SGF parameter space, reducing the candidate
field from hundreds of thousands to only a few thousand spectra. We
then manually search these candidate spectra for Ni II 1393.33 Å
absorption. Following detection, we focus on the Cl I 1391.66 Å
line to observe the influence of UV bursts over lower chromospheric
dynamics. This is done by constructing a series of space-time plots of
the peak intensity, Doppler velocity, and line width SGF parameters
of Cl I 1391.66 Å to measure time lags between its intensification
and broadening, allowing us to estimate downflow velocities in the
lower chromosphere under UV burst conditions. This is possible because
the peak intensity of Cl I 1391.66 Å is dependent on fluorescence
from C II 1335.71 Å, a line strongly emitted by the UV burst source,
while its width only broadens when the emitting material is impacted
by a material flow. This study establishes the power of UV bursts as
probes of dynamical phenomena in the lower chromosphere, a region that
is notoriously difficult to observe directly. Furthermore, it lays the
groundwork for future exploration of the often overlooked cool emission
lines in the IRIS spectral passbands and their potential as physical
diagnostics. This work is part of the NSF-REU Solar Physics program at
SAO, grant number AGS-1850750. Keywords: Solar Magnetic Reconnection,
Active Solar Chromosphere, Solar Ultraviolet Emission.
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Title: An Airborne Coronal Emission Surveyor (ACES) for Total Solar
Eclipse Observations
Authors: Samra, Jenna; Cheimets, Peter; DeLuca, Edward; Madsen, Chad;
Marquez, Vanessa
2021AGUFMED13B..01S Altcode:
The Airborne Coronal Emission Surveyor (ACES) is a new imaging Fourier
transform spectrometer (FTS) that will explore the large-scale
coronal infrared (IR) emission spectrum during the April 8, 2024
total solar eclipse. ACES will fly along the path of totality on the
NSF/NCAR Gulfstream V High-performance Instrumented Airborne Platform
for Environmental Research (GV HIAPER), with a stabilized solar feed
provided by the Airborne Stabilized Platform for InfraRed Experiments
(ASPIRE). During the 6-minute total eclipse, ACES will map emission
line intensity in the 14 micron wavelength region at over a 0.73 0.5
field of view (FOV). A GV altitude of at least 13 km will enable it to
survey the near and mid-IR with minimal atmospheric interference. ACES
is the latest in a line of NSF-funded airborne instruments developed by
Smithsonian Astrophysical Observatory to explore the IR emission corona
from GV HIAPER. Previous instruments include the Airborne InfraRed
Spectrometer (AIR-Spec), a cryogenic grating spectrometer that observed
the 2017 and 2019 eclipses, and ASPIRE, which improves on the AIR-Spec
image stabilization system to provide a 20 cm solar feed stabilized to
5 arcsec RMS over 1 second. Unlike AIR-Spec, which observed a narrow
range of wavelengths and imaged along only one dimension, ACES will
survey the entire 14 micron (2,50010,000 cm-1) spectral range at high
(0.2 cm-1) spectral resolution and in two spatial dimensions. ACES is
expected to observe neutral helium as well as 18 forbidden lines of
ionized magnesium, silicon, sulfur, argon, calcium, and iron, and it
may measure weaker lines of those and other ions. The mission addresses
science questions related to the strength of different emission lines in
different regions of the corona, the relative radiative to collisional
excitation in each line, the best temperature and density diagnostics
in the passband, and the variation of elemental abundances across the
corona. The instrument consists of a condenser telescope, cryogenic
Michaelson interferometer, achromatic lens, and IR camera. The 2024
eclipse flight will serve as the ACES commissioning flight.
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Title: Calibration of the Marshall Grazing Incidence X-Ray
Spectrometer Experiment. II. Flight Instrument Calibration
Authors: Athiray, P. S.; Winebarger, Amy R.; Champey, Patrick;
Kobayashi, Ken; Savage, Sabrina; Beabout, Brent; Beabout, Dyana;
Broadway, David; Bruccoleri, Alexander R.; Cheimets, Peter;
Golub, Leon; Gullikson, Eric; Haight, Harlan; Heilmann, Ralf K.;
Hertz, Edward; Hogue, William; Johnson, Steven; Kegley, Jeffrey;
Kolodziejczak, Jeffery; Madsen, Chad; Schattenburg, Mark L.; Siler,
Richard; Vigil, Genevieve D.; Wright, Ernest
2021ApJ...922...65A Altcode:
The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a
sounding rocket experiment that observes the soft X-ray spectrum of
the Sun from 6.0-24 Å (0.5-2.0 keV), successfully launched on 2021
July 30. End-to-end alignment of the flight instrument and calibration
experiments are carried out using the X-ray and Cryogenic Facility
at NASA Marshall Space Flight Center. In this paper, we present the
calibration experiments of MaGIXS, which include wavelength calibration,
measurement of line spread function, and determination of effective
area. Finally, we use the measured instrument response function to
predict the expected count rates for MaGIXS flight observation looking
at a typical solar active region.
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Title: Calibration of the MaGIXS experiment II: Flight Instrument
Calibration
Authors: Athiray, P. S.; Winebarger, Amy R.; Champey, Patrick;
Kobayashi, Ken; Savage, Sabrina; Beabout, Brent; Beabout, Dyana;
Broadway, David; Bruccoleri, Alexander R.; Cheimets, Peter;
Golub, Leon; Gullikson, Eric; Haight, Harlan; Heilmann, Ralf K.;
Hertz, Edward; Hogue, William; Johnson, Steven; Kegley, Jeffrey;
Kolodziejczak, Jeffery; Madsen, Chad; Schattenburg, Mark L.; Siler,
Richard; Vigil, Genevieve D.; Wright, Ernest
2021arXiv210901720A Altcode:
The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a
sounding rocket experiment that observes the soft X-ray spectrum of
the Sun from 6.0 - 24 Angstrom (0.5 - 2.0 keV), successfully launched
on 30 July 2021. End-to-end alignment of the flight instrument
and calibration experiments are carried out using the X-ray and
Cryogenic Facility (XRCF) at NASA Marshall Space Flight Center. In
this paper, we present the calibration experiments of MaGIXS, which
include wavelength calibration, measurement of line spread function,
and determination of effective area. Finally, we use the measured
instrument response function to predict the expected count rates for
MaGIXS flight observation looking at a typical solar active region
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Title: Characterization of UV Bursts Using Line-Ratio Density
Diagnostics
Authors: Conneely, F.; Madsen, C. A.; DeLuca, E.
2020AGUFMSH0010005C Altcode:
We compare abundance-sensitive and abundance-insensitive electron
density diagnostics for a large sample of UV burst spectra. These bursts
are compact (~1 arcsec), short-lived (~minutes to hours) active-region
phenomena, forming in the cool lower solar atmosphere and capable of
reaching nearly 100,000K. They exhibit significant intensification and
broadening/splitting of the Si IV 1393.76/1402.77 Å lines, which we
believe are signatures of magnetic reconnection. Bursts also display
absorption from cool metallic ions Ni II and Fe II, suggesting that they
form deep in the chromosphere. These unusual phenomena are critical to
understanding energy and mass transfer within the solar atmosphere,
possibly contributing to upper-chromospheric and coronal heating and
affecting the energetics and dynamics of the lower atmosphere. We
employ a semi-automated detection algorithm to assemble a sample of
over 9,800 UV burst spectra for Interface Region Imaging Spectrograph
(IRIS) observations of two active regions spanning several days. <P
/>We perform line-ratio density diagnostics using O IV and S IV pairs as
well as a Si IV / O IV ratio. Since bursts are characterized by strong
Si IV 1402.77 Å emission and O IV 1401.16 Å also appears strongly in a
majority of burst spectra, the Si IV / O IV diagnostic has the potential
to be a robust density indicator. There is a significant uncertainty
around the use of different-species diagnostics due to their strong
dependence on relative atomic abundances, which are poorly constrained
in the chromosphere. We compare the Si IV / O IV diagnostic with the
abundance-insensitive ratios of O IV 1399.78 Å / O IV 1401.16 Å, O IV
1401.16 Å / O IV 1404.81 Å, and S IV 1404.85 Å / S IV 1406.06 Å and
comment on the viability of the Si IV /O IV method in burst regions. We
also find the rates of detection for these lines in our spectra. Our
density analysis provides useful constraints on UV burst formation
altitudes and aids in the comparison of observations to models. <P
/>This work is supported by the NSF-REU Solar Physics program at SAO,
grant number AGS-1850750 and NASA H-SR grant number 80NSSC18K1124.
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Title: EUV imaging and spectroscopy for improved space weather
forecasting
Authors: Golub, Leon; Cheimets, Peter; DeLuca, Edward E.; Madsen, Chad
A.; Reeves, Katharine K.; Samra, Jenna; Savage, Sabrina; Winebarger,
Amy; Bruccoleri, Alexander R.
2020JSWSC..10...37G Altcode:
Accurate predictions of harmful space weather effects are mandatory
for the protection of astronauts and other assets in space, whether in
Earth or lunar orbit, in transit between solar system objects, or on the
surface of other planetary bodies. Because the corona is multithermal
(i.e., structured not only in space but also in temperature),
wavelength-separated data provide crucial information that is not
available to imaging methods that integrate over temperature. The
extreme ultraviolet (EUV) wavelengths enable us to focus directly on
high temperature coronal plasma associated with solar flares, coronal
mass ejections (CMEs), and shocked material without being overwhelmed by
intensity from the solar disk. Both wide-field imaging and spectroscopic
observations of the solar corona taken from a variety of orbits (e.g.,
Earth, L1, or L5) using suitably-chosen EUV instrumentation offer
the possibility of addressing two major goals to enhance our space
weather prediction capability, namely: (1) Improve our understanding
of the coronal conditions that control the opening and closing of the
corona to the heliosphere and consequent solar wind streams, and (2)
Improve our understanding of the physical processes that control the
early evolution of CMEs and the formation of shocks, from the solar
surface out into the extended corona.
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Title: Eclipse Results from the Airborne Infrared Spectrometer
(AIR-Spec) and the Extreme-ultraviolet Imaging Spectrometer (EIS)
Authors: Tañón Reyes, N.; Samra, J.; Madsen, C.; DeLuca, E.
2020AAS...23521009T Altcode:
The Sun's dynamic outermost atmospheric layer, the corona, exhibits
extremely high temperatures meaning it's in a state of hydrostatic
and thermodynamic disequilibrium which leads to solar activity,
such as flares and coronal mass ejections. This activity can
dramatically affect humanity's infrastructure and technology in
space and on Earth. Understanding the coronal magnetic field would
allow for predictions of these magnetic reconnection-driven violent
events. Measuring the magnetic field is possible via the study of
magnetically sensitive emission lines in the infrared (IR) via the
Zeeman effect. The corona emits some IR emission lines, however, the
solar surface's intensity overwhelms them. To study these lines, we can
observe total solar eclipses wherein the moon blocks out the surface's
continuous emission. The Airborne Infrared Spectrometer (AIR-Spec) is
a pathfinder for future infrared spectrometers and spectro-polarimeters
that will measure the coronal magnetic field. On July 2, 2019 AIR-Spec
observed the total solar eclipse over the South Pacific from onboard
an aircraft. It flew at 13km to avoid low-altitude water vapor, the
primary absorber of IR radiation on Earth. AIR-Spec characterized four
emission lines to determine their viability for future instruments to
measure the coronal magnetic field. Comparing the intensity gradients
for the observed IR lines with extreme-ultraviolet (EUV) lines from
the EUV Imaging Spectrometer (EIS) gives us information regarding
the excitation processes in the corona, providing improvements to the
atomic models. We also determine the value of the IR lines as plasma
temperature and density diagnostics, using EIS data to supplement
our analysis. The analysis of the temperature and density will help
explain the behavior of the plasma, which will allow the mapping of the
coronal magnetic field. Lastly, we discuss how AIR-Spec will continue
its mission during both the 2020 and 2024 total solar eclipses as
well as its influence on future spectro-polarimetric missions. This
work is supported by the NSF-REU solar physics program at SAO [grant#
AGS-1560313] and the NSF Airborne InfraRed Spectrograph (AIR-Spec)
2019 Eclipse Flight [award# 1822314].
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Title: Total Solar Eclipse Science and Outreach in Perú
Authors: Tañón Reyes, N.; Madsen, C.
2020AAS...23523907T Altcode:
On July 2nd, 2019, the Airborne Infrared Spectrometer (AIR-Spec)
observed the total solar eclipse over the South Pacific from onboard
an aircraft as a pathfinder for future infrared spectrometers and
spectro-polarimeters that will measure the Sun's coronal magnetic
field. In addition to research, we led outreach activities in Spanish,
including lectures and tours, regarding the scientific importance of
studying solar eclipses for predicting solar activity. The lecture was
a 45-minute talk in Spanish at the Universidad Nacional de Ingeniería
(trans. National University of Engineering) in Lima, Perú. The
next day, following the lecture, we spoke with the local media,
embassy officials and local scientists in Spanish about our project and
instrument. This meeting with journalists led to a front-page story in a
local newspaper regarding our scientific study, allowing the science to
reach a broad audience across the capital. Through these interactions,
we learned colloquia and other research-oriented outreach events in
Spanish are rare. Therefore, this information is largely inaccessible to
those who are not fluent in English, stressing the need for this type of
work in Spanish-speaking communities. While preparing for these events,
we learned that fellow native Spanish speakers at our home institution
have not given a colloquium in Spanish and were not comfortable with
the idea as they do not have the vocabulary. The scientific papers
and textbooks we read, even those originating from Spanish-speaking
countries, are predominantly in English, and therefore the technical
terms are not easily learned or found. As a result, we recognized if
one does not know English, one loses the opportunity to learn about
the current status of scientific research. Having this information
readily available in Spanish will also allow for more people to get
involved in scientific endeavors and for a better exchange of knowledge
between communities. For that reason, during the eclipse in South
America next year, we plan on hosting more events such as these. This
work is supported by the NSF-REU solar physics program at SAO [grant#
AGS-1560313] and the NSF Airborne InfraRed Spectrograph (AIR-Spec)
2019 Eclipse Flight [award# 1822314].
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Title: The 2019 AIR-Spec Mission: Results from Coordinated Infrared
and EUV Spectroscopic Observations of the Corona During the South
Pacific Total Solar Eclipse
Authors: Madsen, C. A.; Samra, J.; Tañón Reyes, N.; DeLuca, E.
2019AGUFMSH33A..04M Altcode:
After a successful maiden voyage in 2017, The Airborne Infrared
Spectrometer (AIR-Spec) embarked on another observing mission, this
time targeting the July 2, 2019 total solar eclipse over the South
Pacific Ocean. AIR-Spec, designed specifically for operation onboard
aircraft, observes coronal infrared emission lines between 1.4 μm and
3.0 μm during total solar eclipses. It proved its viability during
the August 21, 2017 total solar eclipse and underwent significant
design improvements in preparation for the 2019 mission, resulting
in a vastly reduced thermal background and more precise pointing
control. These improvements allowed for an unprecedented view of the
underexplored near-infrared corona, a wavelength regime critical to the
advancement of solar physics due to the potential for direct coronal
magnetic field measurements via spectrally resolved observations of the
Zeeman effect. In pursuit of this goal, and with coordinated support
from the Extreme-ultraviolet Imaging Spectrometer (EIS), we present
the results from a number of studies involving four infrared lines
detected by AIR-Spec: S XI 1.39 μm, Si X 1.43 μm, S XI 1.92 μm, and
Fe IX 2.85 μm. First, we explore the effects of photoexcitation upon
the Si X 1.43 μm line by comparing its spatial radiance profile to
Si X lines in the EUV, further constraining atomic models of coronal
emission such as CHIANTI. Next, we probe the diagnostic potential
of the electron density-sensitive S XI 1.39/1.92 μm line pair while
characterizing the uncertainties arising from atmospheric absorption in
and around the S XI 1.39 μm line. Also, as an extension to previously
published research, we take advantage of the improved sensitivity and
stability of AIR-Spec to perform more precise temperature diagnostics
using the emission measure (EM) loci method. Finally, we demonstrate
how these results will influence future AIR-Spec missions and upcoming
spectro-polarimetric instruments, including those planned for the Daniel
K. Inouye Solar Telescope (DKIST) as well as a proposed balloon-based
coronagraph for coronal magnetic field measurements.
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Title: High-Altitude Instrumentation for Infrared Observations of
the Solar Corona
Authors: Samra, J.; Cheimets, P.; DeLuca, E.; Golub, L.; Hannigan,
J. W.; Judge, P. G.; Madsen, C. A.; Marquez, V.; Tañón Reyes, N.;
Tomczyk, S.
2019AGUFMSH43B..07S Altcode:
High-altitude infrared remote sensing is a promising new method for
measuring coronal plasma and magnetic fields. We present new results
from a recent airborne eclipse mission and outline concepts for future
airborne and balloon-based instruments for coronal spectroscopy
and spectro-polarimetry. <P />The airborne infrared spectrometer
(AIR-Spec) was commissioned during the 2017 total solar eclipse,
when it observed five infrared coronal emission lines from the NSF
Gulfstream V research jet. These magnetically sensitive emission lines
of highly ionized magnesium, silicon, sulfur, and iron are promising
candidates for future observations of the coronal magnetic field, and
their characterization is an important first step toward developing
the next generation of instrumentation for coronal magnetometry. The
second AIR-Spec research flight took place during the July 2, 2019
total solar eclipse across the south Pacific. Higher sensitivity and
reduced jitter enabled more precise measurements of emission line
properties and plasma density, temperature, and line-of-sight velocity
up to one solar radius from the solar limb. Atmospheric absorption
was significant, even at altitude, and atmospheric modeling was
required to extract accurate line intensities. <P />AIR-Spec is a slit
spectrometer that measures light over a 1.55 solar radius field of view
in three spectral passbands between 1.4 and 3 microns. The successful
eclipse missions overcame a number of engineering challenges, centered
around maintaining adequate resolution and signal-to-noise ratio in
a compact and inexpensive package on a moving platform. AIR-Spec is a
pathfinder for future infrared spectrometers and spectro-polarimeters,
including a balloon-based coronagraph that will measure the global
coronal magnetic field and an airborne spectrometer that will survey
the infrared emission corona during a future eclipse.
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Title: Solar Eclipse Observations from the Ground and Air from 0.31
to 5.5 Microns
Authors: Judge, Philip; Berkey, Ben; Boll, Alyssa; Bryans, Paul;
Burkepile, Joan; Cheimets, Peter; DeLuca, Edward; de Toma, Giuliana;
Gibson, Keon; Golub, Leon; Hannigan, James; Madsen, Chad; Marquez,
Vanessa; Richards, Austin; Samra, Jenna; Sewell, Scott; Tomczyk,
Steven; Vera, Alysha
2019SoPh..294..166J Altcode:
We present spectra and broad-band polarized light data from a novel
suite of instruments deployed during the 21st August 2017 total solar
eclipse. Our goals were to survey solar spectra at thermal infrared
wavelengths during eclipse, and to test new technology for measuring
polarized coronal light. An infrared coronal imaging spectrometer,
flown at 14.3 km altitude above Kentucky, was supported on the ground
by observations from Madras, Oregon (elevation 683 m) and Camp Wyoba
on Casper Mountain, Wyoming (2402 m). In Wyoming we deployed a new
infrared Fourier Transform Spectrometer (FTS), three low-dispersion
spectrometers loaned to us by Avantes, a novel visible-light camera
PolarCam, sensitive to linear polarization, and one of two infrared
cameras from FLIR Systems, the other operated at Madras. Circumstances
of eclipse demanded that the observations spanned 17:19 to 18:26
UT. We analyze spectra of the limb photosphere, the chromosphere,
prominences, and coronal lines from 310 nm to 5.5 μm. We calibrated
data photometrically using the solar disk as a source. Between different
spectrometers, the calibrations were consistent to better than 13%. But
the sensitivities achieved were insufficient to detect coronal lines
from the ground. The PolarCam data are in remarkable agreement with
polarization data from the K-Cor synoptic instrument on Mauna Loa, and
with FLIR intensity data acquired in Madras. We discuss new results,
including a detection of the He I 1083 nm multiplet in emission during
the whole of totality. The combination of the FTS and AIR-Spec spectra
reveals for the first time the effects of the telluric extinction
on the infrared coronal emission lines, to be observed with upcoming
Daniel K. Inouye Solar Telescope.
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Title: Unfolding Overlapped Slitless Imaging Spectrometer Data for
Extended Sources
Authors: Winebarger, Amy R.; Weber, Mark; Bethge, Christian; Downs,
Cooper; Golub, Leon; DeLuca, Edward; Savage, Sabrina; del Zanna,
Giulio; Samra, Jenna; Madsen, Chad; Ashraf, Afra; Carter, Courtney
2019ApJ...882...12W Altcode: 2018arXiv181108329W
Slitless spectrometers can provide simultaneous imaging and spectral
data over an extended field of view, thereby allowing rapid data
acquisition for extended sources. In some instances, when the object
is greatly extended or the spectral dispersion is too small, there
may be locations in the focal plane where emission lines at different
wavelengths contribute. It is then desirable to unfold the overlapped
regions in order to isolate the contributions from the individual
wavelengths. In this paper, we describe a method for such an unfolding,
using an inversion technique developed for an extreme ultraviolet
imaging spectrometer and coronagraph named the COronal Spectroscopic
Imager in the EUV (COSIE). The COSIE spectrometer wavelength range
(18.6-20.5 nm) contains a number of strong coronal emission lines and
several density sensitive lines. We focus on optimizing the unfolding
process to retrieve emission measure maps at constant temperature,
maps of spectrally pure intensity in the Fe XII and Fe XIII lines,
and density maps based on both Fe XII and Fe XIII diagnostics.
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Title: Coronal Plasma Characterization via Coordinated Infrared and
Extreme Ultraviolet Observations of a Total Solar Eclipse
Authors: Madsen, Chad A.; Samra, Jenna E.; Del Zanna, Giulio; DeLuca,
Edward E.
2019ApJ...880..102M Altcode: 2019arXiv190110425M
We present coordinated coronal observations of the 2017 August 21 total
solar eclipse with the Extreme-ultraviolet Imaging Spectrometer (EIS)
and the Airborne Infrared Spectrometer (AIR-Spec). These instruments
provide an unprecedented view of the solar corona in two disparate
wavelength regimes, the extreme ultraviolet (EUV) and the near- to
mid-infrared (IR), opening new pathways for characterizing the complex
coronal plasma environment. During totality, AIR-Spec sampled coronal
IR spectra near the equatorial west limb, detecting strong sources
of Mg VIII, S XI, Si IX, and Si X in two passbands encompassing 1.4-4
μm. We apply an intensity-ratio diagnostic to a strong resonant Fe XII
line pair arising from the coordinated EIS observations. This results
in a high-resolution map of electron density throughout the shared
EIS/AIR-Spec field of view. Electron density measurements allow us to
produce a similar map of plasma temperature using emission measure
(EM) loci analysis as applied to 27 EIS emission lines, providing
temperatures of 10<SUP>6.12</SUP> ± 10<SUP>3.5</SUP> K along the
limb and 10<SUP>6.19</SUP> ± 10<SUP>3.5</SUP> K at about 100″
outward. Applying EM loci analysis to AIR-Spec IR spectra coadded
over two 31″ wide ranges centered at two locations, 30″ and
100″ from the limb, produces temperatures consistent with the EIS
data, albeit suffering from moderate uncertainties. Regardless, we
demonstrate that EUV spectral data are valuable constraints to coronal
IR emission models, and will be powerful supplements for future IR
solar observatories, particularly DKIST.
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Title: Solar Ultraviolet Bursts
Authors: Young, Peter R.; Tian, Hui; Peter, Hardi; Rutten, Robert J.;
Nelson, Chris J.; Huang, Zhenghua; Schmieder, Brigitte; Vissers, Gregal
J. M.; Toriumi, Shin; Rouppe van der Voort, Luc H. M.; Madjarska, Maria
S.; Danilovic, Sanja; Berlicki, Arkadiusz; Chitta, L. P.; Cheung, Mark
C. M.; Madsen, Chad; Reardon, Kevin P.; Katsukawa, Yukio; Heinzel, Petr
2018SSRv..214..120Y Altcode: 2018arXiv180505850Y
The term "ultraviolet (UV) burst" is introduced to describe small,
intense, transient brightenings in ultraviolet images of solar active
regions. We inventorize their properties and provide a definition
based on image sequences in transition-region lines. Coronal signatures
are rare, and most bursts are associated with small-scale, canceling
opposite-polarity fields in the photosphere that occur in emerging flux
regions, moving magnetic features in sunspot moats, and sunspot light
bridges. We also compare UV bursts with similar transition-region
phenomena found previously in solar ultraviolet spectrometry and
with similar phenomena at optical wavelengths, in particular Ellerman
bombs. Akin to the latter, UV bursts are probably small-scale magnetic
reconnection events occurring in the low atmosphere, at photospheric
and/or chromospheric heights. Their intense emission in lines with
optically thin formation gives unique diagnostic opportunities
for studying the physics of magnetic reconnection in the low solar
atmosphere. This paper is a review report from an International Space
Science Institute team that met in 2016-2017.
---------------------------------------------------------
Title: Instrument Calibration of the Interface Region Imaging
Spectrograph (IRIS) Mission
Authors: Wülser, J. -P.; Jaeggli, S.; De Pontieu, B.; Tarbell,
T.; Boerner, P.; Freeland, S.; Liu, W.; Timmons, R.; Brannon, S.;
Kankelborg, C.; Madsen, C.; McKillop, S.; Prchlik, J.; Saar, S.;
Schanche, N.; Testa, P.; Bryans, P.; Wiesmann, M.
2018SoPh..293..149W Altcode:
The Interface Region Imaging Spectrograph (IRIS) is a NASA small
explorer mission that provides high-resolution spectra and images of
the Sun in the 133 - 141 nm and 278 - 283 nm wavelength bands. The
IRIS data are archived in calibrated form and made available to the
public within seven days of observing. The calibrations applied to
the data include dark correction, scattered light and background
correction, flat fielding, geometric distortion correction, and
wavelength calibration. In addition, the IRIS team has calibrated the
IRIS absolute throughput as a function of wavelength and has been
tracking throughput changes over the course of the mission. As a
resource for the IRIS data user, this article describes the details
of these calibrations as they have evolved over the first few years
of the mission. References to online documentation provide access to
additional information and future updates.
---------------------------------------------------------
Title: Results of the IRIS UV Burst Survey, Part I: Active Regions
Tracked Limb to Limb
Authors: Madsen, C. A.; DeLuca, E.
2017AGUFMSH43A2802M Altcode:
We present results from the first phase of an effort to thoroughly
characterize UV bursts within the Interface Region Imaging Spectrograph
(IRIS) data catalogue. The observational signatures of these phenomena
include dramatically intensified and broadened NUV/FUV emission line
profiles with absorption features from cool metallic ions. These
properties suggest that UV bursts originate from plasma at transition
region temperatures (≥ 80,000 K) which is deeply embedded in the
cool lower chromosphere ( 5,000 K). Rigorously characterizing the
energetic and dynamical properties of UV bursts is crucial since they
have considerable potential to heat active region chromospheres and
could provide critical constraints for models of magnetic reconnection
in these regions. The survey first focuses on IRIS observations of
active regions tracked from limb to limb. All observations consist
of large field-of-view raster scans of 320 or 400 steps each, which
allow for widespread detection of many burst profiles at the expense
of having limited short-term time evolution information. We detect
bursts efficiently by applying a semi-automated single-Gaussian
fitting technique to Si IV 1393.8 Å emission profiles that isolates
the distinct burst population in a 4-D parameter space. The robust
sample of NUV/FUV burst spectra allows for precise constraints of
properties critical for modeling reconnection in the chromosphere,
including outflow kinetic energy, density estimates from intensity
ratios of Si IV 1402.8 Å and O IV 1401.2 Å emission lines, and
coincident measures of emission in other wavelengths. We also track
burst properties throughout the lifetimes of their host active regions,
noting changes in detection rate and preferential location as the
active regions evolve. Finally, the tracked active region observations
provide a unique opportunity to investigate line-of-sight effects on
observed UV burst spectral properties, particularly the strength of Ni
II 1393.3 Å absorption, a feature that may be important in identifying
the upward conduction of burst thermal energy through the chromosphere.
---------------------------------------------------------
Title: Exploring the Time Evolution of Cool Metallic Absorption
Features in UV Burst Spectra
Authors: Belmes, K.; Madsen, C. A.; DeLuca, E.
2017AGUFMSH51C2499B Altcode:
UV bursts are compact brightenings in active regions that appear in
UV images. They are identified through three spectroscopic features:
(1) broadening and intensification of NUV/FUV emission lines, (2)
the presence of optically thin Si IV emission, and (3) the presence
of absorption features from cool metallic ions. Properties (2) and (3)
imply that bursts exist at transition region temperatures (≥ 80,000
K) but are located in the cooler lower chromosphere ( 5,000 K). Their
energetic and dynamical properties remain poorly constrained. Improving
our understanding of this phenomena could help us further constrain the
energetic and dynamical properties of the chromosphere, as well as give
us insight into whether or not UV bursts contribute to chromospheric
and/or coronal heating. We analyzed the time evolution of UV bursts
using spectral data from the Interface Region Imaging Spectrograph
(IRIS). We inspected Si IV 1393.8 Å line profiles for Ni II 1393.3
Å absorption features to look for signs of heating. Weakening of
absorption features over time could indicate heating of the cool ions
above the burst, implying that thermal energy from the burst could
rapidly conduct upward through the chromosphere. To detect the spectral
profiles corresponding to bursts, we applied a four-parameter Gaussian
fit to every profile in each observation and took cuts in parameter
space to isolate the bursts. We then manually reviewed the remaining
profiles by looking for a statistically significant appearance of
Ni II 1393.3 Å absorption. We quantified these absorption features
by normalizing the Si IV 1393.8 Å emission profiles and measuring
the maximum fractional extinction in each. Our preliminary results
indicate that Ni II 1393.3 Å absorption may undergo a cycle of
strengthening and weakening throughout a burst's lifetime. However,
further investigation is needed for confirmation. This work is supported
by the NSF-REU solar physics program at SAO, grant number AGS-1560313.
---------------------------------------------------------
Title: ASPIRE - Airborne Spectro-Polarization InfraRed Experiment
Authors: DeLuca, E.; Cheimets, P.; Golub, L.; Madsen, C. A.; Marquez,
V.; Bryans, P.; Judge, P. G.; Lussier, L.; McIntosh, S. W.; Tomczyk, S.
2017AGUFMSH13B2480D Altcode:
Direct measurements of coronal magnetic fields are critical for
taking the next step in active region and solar wind modeling and
for building the next generation of physics-based space-weather
models. We are proposing a new airborne instrument to make these key
observations. Building on the successful Airborne InfraRed Spectrograph
(AIR-Spec) experiment for the 2017 eclipse, we will design and build a
spectro-polarimeter to measure coronal magnetic field during the 2019
South Pacific eclipse. The new instrument will use the AIR-Spec optical
bench and the proven pointing, tracking, and stabilization optics. A new
cryogenic spectro-polarimeter will be built focusing on the strongest
emission lines observed during the eclipse. The AIR-Spec IR camera,
slit jaw camera and data acquisition system will all be reused. The
poster will outline the optical design and the science goals for ASPIRE.
---------------------------------------------------------
Title: Eclipse Science Results from the Airborne Infrared Spectrometer
(AIR-Spec)
Authors: Samra, J.; Cheimets, P.; DeLuca, E.; Golub, L.; Judge, P. G.;
Lussier, L.; Madsen, C. A.; Marquez, V.; Tomczyk, S.; Vira, A.
2017AGUFMSH24A..06S Altcode:
We present the first science results from the commissioning flight
of the Airborne Infrared Spectrometer (AIR-Spec), an innovative
solar spectrometer that will observe the 2017 solar eclipse from
the NSF/NCAR High-Performance Instrumented Airborne Platform for
Environmental Research (HIAPER). During the eclipse, AIR-Spec will
image five magnetically sensitive coronal emission lines between 1.4
and 4 microns to determine whether they may be useful probes of coronal
magnetism. The instrument will measure emission line intensity, FWHM,
and Doppler shift from an altitude of over 14 km, above local weather
and most of the absorbing water vapor. Instrumentation includes an image
stabilization system, feed telescope, grating spectrometer, infrared
camera, and visible slit-jaw imager. Results from the 2017 eclipse
are presented in the context of the mission's science goals. AIR-Spec
will identify line strengths as a function of position in the solar
corona and search for the high frequency waves that are candidates
for heating and acceleration of the solar wind. The instrument will
also identify large scale flows in the corona, particularly in polar
coronal holes. Three of the five lines are expected to be strong in
coronal hole plasmas because they are excited in part by scattered
photospheric light. Line profile analysis will probe the origins
of the fast and slow solar wind. Finally, the AIR-Spec measurements
will complement ground based eclipse observations to provide detailed
plasma diagnostics throughout the corona. AIR-Spec will measure infrared
emission of ions observed in the visible from the ground, giving insight
into plasma heating and acceleration at radial distances inaccessible
to existing or planned spectrometers.
---------------------------------------------------------
Title: Waves, Bursts, and Instabilities: A Multi-Scale Investigation
of Energetic Plasma Processes in the Solar Chromosphere and Transition
Region
Authors: Madsen, Chad Allen
2017PhDT.......264M Altcode:
The chromosphere and transition region of the solar atmosphere provide
an interface between the cool photosphere ( 6000 K) and the hot corona
( 1 million K). Both layers exhibit dramatic deviations from thermal
and hydrostatic equilibrium in the form of intense plasma heating
and mass transfer. The exact mechanisms responsible for transporting
energy to the upper atmosphere remain unknown, but these must include
a variety of energetic processes operating across many spatial and
temporal scales. This dissertation comprises three studies of possible
mechanisms for plasma heating and energy transport in the solar
chromosphere and transition region. The first study establishes the
theoretical framework for a collisional, two-stream plasma instability
in the quiet-Sun chromosphere similar to the Farley-Buneman instability
which actively heats the E-region of Earth's ionosphere. After deriving
a linear dispersion relationship and employing a semi-empirical model of
the chromosphere along with carefully computed collision frequencies,
this analysis shows that the threshold electron drift velocity for
triggering the instability is remarkably low near the temperature
minimum where convective overshoots could continuously trigger the
instability. The second study investigates simultaneous Interface Region
Imaging Spectrograph (IRIS) observations of magnetohydrodynamic (MHD)
waves in the chromospheres and transition regions of sunspots. By
measuring the dominant wave periods, apparent phase velocities,
and spatial and temporal separations between appearances of two
observationally distinct oscillatory phenomena, the data show that these
are consistent with upward-propagating slow magnetoacoustic modes tied
to inclined magnetic field lines in the sunspot, providing a conduit
for photospheric seismic energy to transfer upward. The third and
final study focuses on intense, small-scale ( 1 arcsec) active region
brightenings known as IRIS UV bursts. These exhibit dramatic FUV/NUV
emission line splitting and deep absorption features, suggesting that
they result from reconnection events embedded deep in the cool lower
chromosphere. IRIS FUV spectral observations and Solar Dynamics Obser-
vatory/Helioseismic and Magnetic Imager (SDO/HMI) magnetograms of a
single evolving active region reveal that bursts prefer to form during
the active region's emerging phase. These bursts tend to be spatially
coincident with small-scale, photospheric, bipolar regions of upward
and downward magnetic flux that dissipate as the active region matures.
---------------------------------------------------------
Title: Initial Results of a Large-scale Statistical Survey of
Small-scale UV Bursts with IRIS and SDO
Authors: Madsen, C. A.; DeLuca, E.
2016AGUFMSH31B2570M Altcode:
UV bursts are small-scale ( 1 arcsec or less) brightenings observed
in the NUV/FUV passbands of the Interface Region Imaging Spectrograph
(IRIS). These peculiar phenomena are found exclusively in active regions
and exhibit dramatic and defining spectroscopic characteristics. In
particular, they present intense broadening and splitting, often
in excess of 70 km s-1, in all bright emission lines observable by
IRIS. Furthermore, these broadened lines also display strong absorption
from cool metallic ions such as Fe II and Ni II which typically
populate the chromosphere. These features suggest that bursts are
bidirectional plasma flows at transition region temperatures embedded
much farther down in the cool chromosphere. To better characterize
these phenomena, we have launched a statistical survey encompassing
the entire IRIS data catalogue to date and its accompanying data from
the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic
Imager (HMI). We sample a wide variety of IRIS observations of Si IV
lines, ranging from large 400-step rasters for large detection rates
to short-cadence sit-and-stare observations to provide in-depth time
evolution data of individual bursts. Detection is streamlined by a
semi-automated method that isolates characteristic burst spectra based
on single-Gaussian fit parameters, greatly reducing search times in the
vast IRIS catalogue. Our initial results demonstrate that UV bursts
tend to appear when active regions are young and actively emerging,
preferring to populate poorly developed inversion lines composed
of numerous small mixed-polarity regions. Burst occurrence rates
peak at 30-70 per hour in young active regions, decreasing as those
regions age. We also find dramatic variations in spectral morphology
in spatial scans of bursts with many split into distinct, opposing,
resolved regions of blueshifts and redshifts. Finally, we find little
evidence for coronal counterparts in AIA 171 Å, but we do find that
a significant ratio of bursts coincide with localized bright features
in AIA 1700 Å, lending support to the link between bursts and Ellerman
bombs. With further involvement in the survey, we hope to constrain the
burst/Ellerman bomb coincidence, the time evolution of burst spectral
morphologies, and the distribution of their peak kinetic energies.
---------------------------------------------------------
Title: Tracking Sunspot Waves Across the Solar Disk using IRIS
Authors: Sager, H. A.; Madsen, C. A.; DeLuca, E.
2016AGUFMSH21E2568S Altcode:
Waves can be observed in the transition region and upper chromosphere of
sunspots. Two particular phenomena, running waves and umbral flashes,
can be seen in the 1400 Å and 2796 Å bandpasses, respectively,
on slit-jaw images from the Interface Region Imaging Spectrograph
(IRIS). How running waves propagate through the solar atmosphere is
still a topic of debate revolving around two theories. The trans-sunspot
theory explains that these waves propagate radially across the sunspot
from its center just as they appear visually. The upward propagating
theory illustrates that these waves are tied to the magnetic field
lines and are therefore slow magnetoacoustic waves, indicating that the
observed apparent motion of the waves is not real. Previous studies
focused on individual observations at a fixed viewing angle, leaving
the results susceptible to line-of-sight bias. To test for this bias, we
observed the leading sunspots of AR 11836 and AR 12546 as they traveled
from the disk center to the western limb. To assess the two theories,
we applied global wavelet analysis to our high-pass filtered slit-jaw
images and were able to find the spatial distribution of dominate wave
periods for both phenomena. We then compared the period distribution
to magnetic field line inclinations from the Helioseismic and Magnetic
Imager (HMI). From this, we find a clear correlation between magnetic
field line inclination and wave period as both increase outward from the
sunspot center. The period increases from 180 s from the sunspot center
to 240 s near the edge of the penumbra for all of our viewing angles,
nullifying the existence of a line-of-sight bias and lending credence
to the upward propagating theory. The importance of discovering how
these waves are moving through the solar atmosphere could provide a
mechanism for transporting local seismic energy from the photosphere
to the corona.
---------------------------------------------------------
Title: Are IRIS Bombs Connected to Ellerman Bombs?
Authors: Tian, Hui; Xu, Zhi; He, Jiansen; Madsen, Chad
2016ApJ...824...96T Altcode: 2016arXiv160405423T
Recent observations by the Interface Region Imaging Spectrograph
(IRIS) have revealed pockets of hot gas (∼2-8 × 10<SUP>4</SUP> K)
potentially resulting from magnetic reconnection in the partially
ionized lower solar atmosphere (IRIS bombs; IBs). Using joint
observations between IRIS and the Chinese New Vacuum Solar Telescope,
we have identified 10 IBs. We find that 3 are unambiguously and 3
others are possibly connected to Ellerman bombs (EBs), which show
intense brightening of the extended {{{H}}}<SUB>α </SUB> wings without
leaving an obvious signature in the {{{H}}}<SUB>α </SUB> core. These
bombs generally reveal the following distinct properties: (1) the O
IV 1401.156 Å and 1399.774 Å lines are absent or very weak; (2) the
Mn I 2795.640 Å line manifests as an absorption feature superimposed
on the greatly enhanced Mg II k line wing; (3) the Mg II k and h lines
show intense brightening in the wings and no dramatic enhancement in the
cores; (4) chromospheric absorption lines such as Ni II 1393.330 Å and
1335.203 Å are very strong; and (5) the 1700 Å images obtained with
the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory
reveal intense and compact brightenings. These properties support the
formation of these bombs in the photosphere, demonstrating that EBs
can be heated much more efficiently than previously thought. We also
demonstrate that the Mg II k and h lines can be used to investigate EBs
similarly to {{{H}}}<SUB>α </SUB>, which opens a promising new window
for EB studies. The remaining four IBs obviously have no connection
to EBs and they do not have the properties mentioned above, suggesting
a higher formation layer, possibly in the chromosphere.
---------------------------------------------------------
Title: Observations of Small-scale IRIS Bombs (Reconnection Events)
in an Evolving Active Region
Authors: Madsen, C. A.; Tian, H.; DeLuca, E. E.
2015AGUFMSH31B2414M Altcode:
We present the first Interface Region Imaging Spectrograph (IRIS)
observations of small-scale bombs evolving with their host active
region. Bombs appear most clearly in the IRIS 1330 Å and 1400 Å
slit-jaw images as small (~1 arcsec), compact, intense brightenings at
transition region temperatures. Their NUV/FUV emission spectra exhibit
dramatic line splitting and strong absorption features indicative of
bidirectional flows from magnetic reconnection embedded deep within the
cool lower solar atmosphere. The bombs may contribute significantly
to the heating of the solar atmosphere in active regions; however,
it's unclear how prevalent the bombs are throughout the lifetime of an
active region. Using a semi-automated detection method, we locate bombs
within AR 11850 over the course of four observations from 06:00 UT on
September 25, 2013 until 11:30 UT the next day. The active region is
first observed in an emerging phase and rapidly grows into a mature
active region with well-developed sunspots. The bomb occurrence rate
drops dramatically as the active region fully emerges. We also find
that the bombs fall into two distinct populations: one appears largely
during active region emergence and contains a majority of the bombs,
while the other population is present regardless of active region
age. The first population of bombs is typically found embedded in the
low-lying loops prominent in the young active region. Furthermore,
we use Solar Dynamics Observatory/Helioseismic and Magnetic Imager
(SDO/HMI) line-of-sight magnetograms to show that the bombs associated
with the first population occur at the boundaries between the upward
and downward flux of small, isolated bipolar regions. These regions
dissipate as the active region emerges and reconfigures its magnetic
field into two large network patches of upward and downward flux with a
clear inversion line. The second, smaller population of bombs usually
occurs far from the active region loop structures in the plage and
sunspot penumbrae. They are associated with the boundaries between
strong upward or downward flux and regions where the magnetic field
is perpendicular to the line of sight.
---------------------------------------------------------
Title: Observations of Umbral Flashes and Running Sunspot Waves with
the Interface Region Imaging Spectrograph
Authors: Madsen, Chad A.; Tian, Hui; DeLuca, Edward E.
2015ApJ...800..129M Altcode:
We present simultaneous, high-resolution, multi-temperature observations
of running waves and umbral flashes in a sunspot with the Interface
Region Imaging Spectrograph. We analyze intensity variations in
slit-jaw images to investigate the relationship between running
waves in the 1400 Å (Si IV/transition region) passband and umbral
flashes in the 2796 Å (Mg II/chromosphere) passband. Using global
wavelet analysis, we find that the dominant wave periods increase
from approximately 150 s near the sunspot center to about 300 s in
the penumbra in both passbands. This coincides extremely well with
the radially increasing inclination of magnetic field lines observed
with Solar Dynamics Observatory/Helioseismic and Magnetic Imager,
suggesting that the waves are propagating vertically along the inclined
field lines. Furthermore, apparent horizontal velocities for running
waves decrease from about 12 km s<SUP>-1</SUP> in the umbra to about
4 km s<SUP>-1</SUP> in the penumbra which is predicted by the same
inclined field geometry. Finally, we find that umbral flashes lead
running waves in both the spatial and temporal domains. The former
result is attributable to the inclined field geometry; however, the
geometry does not predict the radially increasing time lag which is
likely due to the opacity difference between the emission lines that
dominate the two passbands. These results suggest that running waves
and umbral flashes both originate from photospheric p-mode oscillations
and are manifestations of upward-propagating slow magnetoacoustic modes
at different altitudes and temperatures. The apparent trans-sunspot
propagation of running waves is not real but rather an image of these
upward-propagating modes traveling along field lines of radially
increasing inclination.
---------------------------------------------------------
Title: Jorge Melnick Retires from ESO
Authors: Madsen, C.
2014Msngr.158...59M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: First Simulations of a Collisional Two-Stream Instability in
the Chromosphere
Authors: Oppenheim, Meers; Dimant, Yakov; Madsen, Chad Allen;
Fontenla, Juan
2014AAS...22430205O Altcode:
Observations and modeling shows that immediately above the temperature
minimum in the solar atmosphere, a steep rise from below 4,000 K to
over 6,000K occurs. Recent papers show that a collisional two-stream
plasma instability called the Farley-Buneman Instability can develop
at the altitudes where this increase occurs. This instability may
play an important role in transferring energy from turbulent neutral
flows originating in the photosphere to the mid-chromosphere in the
form of heat. Plasma turbulence resulting from this instability could
account for some or most of this intense chromospheric heating. This
paper presents a set of simulations showing the development and
evolution of the Farley-Buneman Instability (FBI) applicable to the
chromosphere. It compares these results with the better-understood
ionospheric FBI. It examines the linear behavior and the dependence
of growth rates for a range of altitudes and driving flows. It also
presents the first study of FBI driven plasma nonlinearities and
turbulence in the chromosphere. This research should help us evaluate
the FBI as a mechanism to convert neutral flow and turbulence energy
into electron thermal energy in the quiet Sun.
---------------------------------------------------------
Title: Theory of Collisional Two-Stream Plasma Instabilities in the
Solar Chromosphere
Authors: Madsen, Chad Allen; Dimant, Yakov; Oppenheim, Meers;
Fontenla, Juan
2014AAS...22432303M Altcode:
The solar chromosphere experiences intense heating just above its
temperature minimum. The heating increases the electron temperature
in this region by over 2000 K. Furthermore, it exhibits little time
variation and appears widespread across the solar disk. Although
semi-empirical models, UV continuum observations, and line emission
measurements confirm the existence of the heating, its source remains
unexplained. Potential heating sources such as acoustic shocks,
resistive dissipation, and magnetic reconnection via nanoflares
fail to account for the intensity, persistence, and ubiquity of the
heating. Fontenla (2005) suggested turbulence from a collisional
two-stream plasma instability known as the Farley-Buneman instability
(FBI) could contribute significantly to the heating. This instability
is known to heat the plasma of the E-region ionosphere which bears many
similarities to the chromospheric plasma. However, the ionospheric
theory of the FBI does not account for the diverse ion species found
in the solar chromosphere. This work develops a new collisional,
two-stream instability theory appropriate for the chromospheric plasma
environment using a linear fluid analysis to derive a new dispersion
relationship and critical E x B drift velocity required to trigger the
instability. Using a 1D, non-local thermodynamic equilibrium, radiative
transfer model and careful estimates of collision rates and magnetic
field strengths, we calculate the trigger velocities necessary to induce
the instability throughout the chromosphere. Trigger velocities as low
as 4 km s^-1 are found near the temperature minimum, well below the
local neutral acoustic speed in that region. From this, we expect the
instability to occur frequently, converting kinetic energy contained
in neutral convective flows from the photosphere into thermal energy
via turbulence. This could contribute significantly to chromospheric
heating and explain its persistent and ubiquitous nature.
---------------------------------------------------------
Title: The Multi-species Farley-Buneman Instability in the Solar
Chromosphere
Authors: Madsen, Chad A.; Dimant, Yakov S.; Oppenheim, Meers M.;
Fontenla, Juan M.
2014ApJ...783..128M Altcode: 2013arXiv1308.0305M
Empirical models of the solar chromosphere show intense electron
heating immediately above its temperature minimum. Mechanisms such as
resistive dissipation and shock waves appear insufficient to account for
the persistence and uniformity of this heating as inferred from both
UV lines and continuum measurements. This paper further develops the
theory of the Farley-Buneman instability (FBI) which could contribute
substantially to this heating. It expands upon the single-ion theory
presented by Fontenla by developing a multiple-ion-species approach
that better models the diverse, metal-dominated ion plasma of the solar
chromosphere. This analysis generates a linear dispersion relationship
that predicts the critical electron drift velocity needed to trigger
the instability. Using careful estimates of collision frequencies and
a one-dimensional, semi-empirical model of the chromosphere, this new
theory predicts that the instability may be triggered by velocities as
low as 4 km s<SUP>-1</SUP>, well below the neutral acoustic speed. In
the Earth's ionosphere, the FBI occurs frequently in situations where
the instability trigger speed significantly exceeds the neutral acoustic
speed. From this, we expect neutral flows rising from the photosphere
to have enough energy to easily create electric fields and electron
Hall drifts with sufficient amplitude to make the FBI common in the
chromosphere. If so, this process will provide a mechanism to convert
neutral flow and turbulence energy into electron thermal energy in
the quiet Sun.
---------------------------------------------------------
Title: Retirement of Massimo Tarenghi
Authors: Madsen, C.
2013Msngr.153...39M Altcode:
Massimo Tarenghi, chronologically MPG/ESO project scientist, NTT project
manager, VLT programme manager and first Director, ALMA Director and
ESO Representative in Chile, has retired after 35 years at ESO. A
brief summary of his achievements is presented.
---------------------------------------------------------
Title: Presenting the ESO Story: One Hundred and Fifty Messengers
Authors: Madsen, C.
2012Msngr.150...74M Altcode:
Since 1974, The ESO Messenger has been one of ESO's primary
communication channels to the outside world in particular. It has
provided a window not only onto the organisation, its projects and
people, but also onto the research carried out by ESO's ever-growing
user community. Last but not least, today it constitutes a fascinating
historical source, documenting the life and evolution of ESO over the
last 38 years.
---------------------------------------------------------
Title: Large-Scale Intrinsic Alignments of Galaxies
Authors: Brainerd, Tereasa G.; Agustsson, I.; Madsen, C. A.; Edmonds,
J. A.
2010AAS...21540906B Altcode: 2010BAAS...42..234B
We compute the two-point image correlation function for bright
galaxies in the seventh data release of the Sloan Digital Sky Survey
(SDSS) over angular scales 0.01 arcmin to 120 arcmin and projected
separations 0.01 Mpc to 10 Mpc. We restrict our analysis to SDSS
galaxies with spectroscopic redshifts and we find strong evidence for
intrinsic alignment of the galaxy images. On scales greater than 40
kpc, the intrinsic alignment of the SDSS galaxy images compares well
with the intrinsic alignment of galaxy images in a LCDM universe,
provided we impose Gaussian-random errors on the position angles of
the theoretical galaxies with a dispersion of 25 degrees. Without
the inclusion of these errors, the amplitude of the two-point image
correlation function for the theoretical galaxies is a factor of
2 higher than it is for the SDSS galaxies. We interpret this as a
combination of modest position angle errors for the SDSS galaxies,
as well as a need for modest misalignment of mass and light in the
theoretical galaxies. The intrinsic alignment of the SDSS galaxies shows
no dependence on the specific star formation rates of the galaxies and,
at most, a very weak dependence on the colors and stellar masses of
the galaxies. At the 3 sigma level, however, we find an indication
that the images of the most luminous SDSS galaxies are more strongly
aligned with each other than are the images of the least luminous SDSS
galaxies. This work was supported by NSF grant AST-0708468.
---------------------------------------------------------
Title: Large-Scale Intrinsic Alignment of Galaxy Images
Authors: Brainerd, Tereasa G.; Agustsson, Ingolfur; Madsen, Chad A.;
Edmonds, Jeffrey A.
2009arXiv0904.3095B Altcode:
We compute the two-point image correlation function for bright galaxies
in the seventh data release of the Sloan Digital Sky Survey (SDSS) over
angular scales 0.01' <= \theta <= 120' and projected separations
0.01 Mpc <= r <= 10 Mpc. We restrict our analysis to SDSS galaxies
with accurate spectroscopic redshifts, and we find strong evidence for
intrinsic alignment of the galaxy images. On scales greater than r ~
40 kpc, the intrinsic alignment of the SDSS galaxy images compares well
with the intrinsic alignment of galaxy images in a Lambda-CDM universe,
provided we impose Gaussian-random errors on the position angles of
the theoretical galaxies with a dispersion of 25 degrees. Without
the inclusion of these errors, the amplitude of the two-point image
correlation function for the theoretical galaxies is a factor of
~2 higher than it is for the SDSS galaxies. We interpret this as a
combination of modest position angle errors for the SDSS galaxies,
as well as a need for modest misalignment of mass and light in the
theoretical galaxies. The intrinsic alignment of the SDSS galaxies shows
no dependence on the specific star formation rates of the galaxies and,
at most, a very weak dependence on the colors and stellar masses of the
galaxies. At the ~3-sigma level, however, we find an indication that
the images of the most luminous SDSS galaxies are more strongly aligned
with each other than are the images of the least luminous SDSS galaxies.
---------------------------------------------------------
Title: ASTRONET: Public Outreach
Authors: Ros, R. M.; Fosbury, R.; Christensen, L. L.; Del Toro Iniesta,
J. C.; Fucili, L.; Hill, R.; Lorenzen, D.; Madsen, C.; Newsam, A.;
Pickwick, A.; Radeva, V.
2009CAPJ....5...26R Altcode:
We have all seen the spectacular images that the Hubble Space Telescope
and other such observatories have revealed to the world. Their haunting
splendour inspires and compels us as artists. But how can we capture
the elusive essence of space in our own work?
---------------------------------------------------------
Title: ESO Education and Public Outreach for IYA2009
Authors: Pierce-Price, D.; Madsen, C.; Boffin, H. J.; Argandoña, G.
2008ca07.conf..274P Altcode:
ESO, the European Organisation for Astronomical Research in the Southern
Hemisphere, is planning a range of education and public outreach
activities for the International Year of Astronomy 2009 (IYA2009). In
addition to support for IYA2009 global Cornerstone Projects, these
will include local, national, and international activities, aimed at
the general public, the interested public, and school students.
---------------------------------------------------------
Title: ESO at the AAS, the AAAS and in Dublin
Authors: Boffin, H.; Madsen, C.
2007Msngr.127...69B Altcode:
The great variety of new distribution meth-ods and tools available
does not replace face-to-face communication, which re-mains a most
valuable activity in presenting ESO and its future needs. Face-to-face
communication, in turn, takes many forms ranging from formal lectures
and speeches, through less formal and infor-mal meetings and briefings,
e.g. with de-cision makers or media representatives, to information
stands at fairs and confer-ences. Information stands often provide a
physical basis for important personal encounters. In 2006, ESO's Public
Affairs Department organised or participated in more than 20 events,
involving exhibitions, briefings and VIP visits. This con-stitutes a
marked increase over the pre-vious years, on the one hand reflecting
the growing importance and visibility of ESO, and, on the other hand,
a necessity, given the need to enlist wide support for ESO's ambitious
future projects.
---------------------------------------------------------
Title: Open House at the ESO Headquarters
Authors: Madsen, C.
2006Msngr.126...50M Altcode: 2006Msngr.126f..50M
On 15 October, the ESO Headquarters opened its doors to the public
as part of the All-Campus Open House organised in connection with the
inauguration of the extension of the underground line U6 from Munich to
the Garching campus. The day was blessed with clear skies and plenty
of sunshine, and a large number of citizens took advantage of the
opportunity to visit the campus. The estimated number of visitors at
ESO was close to 3000 people, a record number. Another record was set
by the number of ESO staff who, in anticipation of the high num-ber
of guests, volunteered to spend their Sunday at work to explain what
ESO is doing and why it is important.
---------------------------------------------------------
Title: Universe Awareness For Young Children
Authors: Scorza, C.; Miley, G.; Ödman, C.; Madsen, C.
2006IAUSS...2E..39S Altcode:
Universe Awareness (UNAWE) is an international programme that will
expose economically disadvantaged young children aged between 4 and 10
years to the inspirational aspects of modern astronomy. The programme
is motivated by the premise that access to simple knowledge about the
Universe is a basic birth right of everybody. These formative ages
are crucial in the development of a human value system. This is also
the age range in which children can learn to develop a 'feeling' for
the vastness of the Universe. Exposing young children to such material
is likely to broaden their minds and stimulate their world-view. The
goals of Universe Awareness are in accordance with two of the United
Nations Millennium goals, endorsed by all 191 UN member states,
namely (i) the achievement of universal primary education and (ii)
the promotion of gender equality in schools. We propose to commence
Universe Awareness with a pilot project that will target disadvantaged
regions in about 4 European countries (possibly Spain, France, Germany
and The Netherlands) and several non-EU countries (possibly Chile,
Colombia, India, Tunisia, South Africa and Venezuela). There will
be two distinct elements in the development of the UNAWE program:
(i) Creation and production of suitable UNAWE material and delivery
techniques, (ii) Training of educators who will coordinate UNAWE in each
of the target countries. In addition to the programme, an international
network of astronomy outreach will be organised. We present the first
results of a pilot project developed in Venezuela, where 670 children
from different social environments, their teachers and members of an
indigenous tribe called Ye´kuana from the Amazon region took part
in a wonderful astronomical and cultural exchange that is now being
promoted by the Venezuelan ministry of Education at the national level.
---------------------------------------------------------
Title: ESO's Astronomy Education Programme
Authors: Pierce-Price, D. P. I.; Boffin, H.; Madsen, C.
2006IAUSS...2E..23P Altcode:
ESO, the European Organisation for Astronomical Research in the
Southern Hemisphere, has operated a programme of astronomy education
for some years, with a dedicated Educational Office established in
2001. We organise a range of activities, which we will highlight
and discuss in this presentation. Many are run in collaboration with
the European Association for Astronomy Education (EAAE), such as the
"Catch a Star!" competition for schools, now in its fourth year. A
new endeavour is the ALMA Interdisciplinary Teaching Project (ITP). In
conjunction with the EAAE, we are creating a set of interdisciplinary
teaching materials based around the Atacama Large Millimeter Array
project. The unprecedented astronomical observations planned with ALMA,
as well as the uniqueness of its site high in the Atacama Desert,
offer excellent opportunities for interdisciplinary teaching that
also encompass physics, engineering, earth sciences, life sciences,
and culture. Another ongoing project in which ESO takes part is the
"Science on Stage" European science education festival, organised by
the EIROforum - the group of seven major European Intergovernmental
Research Organisations, of which ESO is a member. This is part of the
European Science Teaching Initiative, along with Science in School,
a newly-launched European journal for science educators. Overviews of
these projects will be given, including results and lessons learnt. We
will also discuss possibilities for a future European Astronomy Day
project, as a new initiative for European-wide public education.
---------------------------------------------------------
Title: Walloon Space Days
Authors: Madsen, C.
2006Msngr.124...42M Altcode:
On 28-29 March, the Cluster Wallonie Espace, mainly a partnership
of companies in the Walloon ‘Space Valley', or-ganised the first
so-called ‘W Space Days' at the Colonster Castle, located on the
premises of the University of Liège. The primary aim of these days
is to encourage meetings between professionals in the sector and to
identify new scientific and technological opportunities. They should
also help to raise awareness of the activities of the space sector
amongst the general public and young people in particular. Indeed the
event successfully brought together scientists, industrialists, funding
agencies and policymakers. On the first day, some 210 representatives
of research centres, industries and organisations from 13 countries
in Europe participated in the professional event, while the next
day was a ‘public day'. The first morning's programme comprised a
series of talks, including ELT presentations by Roberto Gilmozzi and
Philippe Dierickx.
---------------------------------------------------------
Title: Finnish Parliamentary Committee at ESO Headquarters
Authors: Madsen, C.
2006Msngr.124...38M Altcode:
Finnish Parliamentary Committee at ESO Headquarters
---------------------------------------------------------
Title: ESO at AAAS
Authors: Madsen, C.
2006Msngr.123...61M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Universe Awareness . An inspirational programme for
economically disadvantaged young children.
Authors: Ödman, C. J.; Scorza, C.; Miley, G. K.; Madsen, C.
2006MmSAI..77.1014O Altcode:
The beauty of the sky and its connection with the human development have
inspired generations with wonder. Astronomy conveys the excitement
of science to the public. Considerable resources are devoted to
outreach in developed countries, with spectacular images produced
by modern astronomical facilities and astronomical discoveries that
change our views of the Universe. <P />Universe Awareness (UNAWE) is a
programme for children between 4 and 10 years old. The formative ages
of 4 to 10 years are crucial in child development. Children of that
age can appreciate the beauty of astronomical objects and develop a
“feeling” for the vastness of the Universe. Exposing young children
to such material is likely to broaden their minds and stimulate their
world-view. The programme concentrates on economically disadvantaged
young children because most other children will be exposed to some
knowledge about the Universe and disparities between advantaged
and disadvantaged children increase with age. Venezuela hosted a
successful pilot project in 2006. From spontaneous observation of the
sky to a teacher-training workshop in the "Centro de Investigaciones
de Astronomía" in Mérida, this was a wonderful experience for
participants and organisers alike. This shows how successful the UNAWE
programme can be.
---------------------------------------------------------
Title: ESO at Cer 2005
Authors: Madsen, C.
2005Msngr.122...48M Altcode:
On November 14-15, the Brussels Exhibition Centre (Heysel) was the home
of a major international conference on science communication with the
title “Communicating European Research” (CER 2005).
---------------------------------------------------------
Title: Science on Stage 2005
Authors: Pierce-Price, D.; Boffin, H.; Madsen, C.
2005Msngr.122...47P Altcode:
“Science on Stage”, the European Science Teaching Festival, is
a major educational outreach programme for science teachers. It aims
to identify and foster innovation within formal science education by
means of exchange of best practice, workshops and seminars involving
educators from all over Europe.
---------------------------------------------------------
Title: Universe Awareness for Young Children
Authors: Miley, G.; Madsen, C.; Scorza de Appl, C.
2005Msngr.121...66M Altcode:
Universe Awareness (UNA) is an international programme that will expose
economically-disadvantaged young children, between ages 4 and 10 years,
in developed and developing countries to the inspirational aspects of
modern astronomy.
---------------------------------------------------------
Title: Towards a Europe of Knowledge and Innovation?
Authors: Madsen, C.
2005Msngr.120...46M Altcode:
THE EUROPEAN SOCIETIES ARE undergoing fast changes these years. The
need to manage the European integration process as well as to develop
adequate solutions in the face of globalization and the pressure on
the ‘European way of life' led the Heads of states and governments
of the EU to set for themselves the goal of developing the most dynamic
knowledge-based economy in the world within a 10-year period. Both the
goals and the policies to reach them are known as the Lisbon Agenda and
the Lisbon Process, respectively, reminding us that it was in the city
of Lisbon - in the year 2000 - that this development was started. Now,
at half-time, the process has been reviewed and the governments have
acknowledged the need to focus on the most essential policy areas that
must be developed to achieve success.
---------------------------------------------------------
Title: Richard West retires
Authors: Madsen, C.
2005Msngr.120...56M Altcode:
It is hard to believe, but after 35 years of service, Richard West has
retired from ESO. Born 1941 in Copenhagen, Richard did his baccalaureate
in 1959. In 1964, he obtained his degree (Mag. scient. et cand. mag.) in
astronomy and astrophysics at Copenhagen University, followed by a
period as Assistant Professor (Amanuensis) at Copenhagen University
Observatory. In 1970, he joined ESO as Assistant Astronomer to the
ESO Director General, Adriaan Blaauw.
---------------------------------------------------------
Title: ESO Presentation in Copenhagen
Authors: Madsen, C.; D'Odorico, S.
2004Msngr.118...71M Altcode:
On November 8, ESO continued its series of presentations in
memberstates with an event in Copenhagen. So far events have been
organised in Belgium, Finland, Portugal, Sweden, Switzerland and
the United Kingdom. The purpose of these presentations is to raise
the awareness of ESO amongst decision-makers, academia and the
media. Over time, the scope and specific focus of the national events
have varied, considering the particular circumstances and the wishes
of the national hosts, and accordingly, the presentation in Denmark
was primarily oriented towards industry. The meeting was initiated
by the Royal Danish Consulate General in Munich in conjunction with
the Confederation of Danish Industries and the Ministry for Science,
Technology and Innovation. Leading up to the meeting, several articles
about ESO had appeared in the Danish press and the 2nd TV Channel
featured a report on the ESO projects also in connection with the event.
---------------------------------------------------------
Title: Report on the EuroScience Open Forum 2004
Authors: Madsen, C.
2004Msngr.117...66M Altcode:
SCIENCE reigned supreme in Stockholm for a period of four days in
late August this year, as some 1800 scientists, administrators,
policy-makers and media representatives from 68 countries convened
at the EUROSCIENCE Open Forum, the first pan- European inter- and
transdisciplinary science meeting on our Continent.
---------------------------------------------------------
Title: Serving European Science: The EIROforum Collaboration
Authors: Madsen, C.
2004Msngr.116...42M Altcode:
OVER THE LAST FEW years, the idea of a “European Research Area”
(ERA) has gained strong support among science policy makers and,
increasingly, among scientists themselves. The goal of the ERA is
to establish a single “market” for research on our continent,
allowing for better co-ordination of research efforts, synergies
between projects, the achievement of “critical mass” (both human
and financial) and thus to strengthen the competitiveness of European
research. These goals necessitate deep structural changes in the way
science is organised, breaking up existing borderlines and barriers
between national research systems in Europe.
---------------------------------------------------------
Title: Visit EIROFORUM at ESOF 2004
Authors: Madsen, C.
2004Msngr.116...48M Altcode:
The EuroScience Open Forum (ESOF2004) is the first pan-European
interdisciplinary scientific conference, modelled on the well-known
and highly successful meetings in the US by the American Association
for the Advancement of Science (AAAS). ESOF2004 will be held at the
Stockholm City Conference Centre in Stockholm, Sweden, this summer,
between 25-28 August. It is intended to continue with ESOF meetings
on a biannual basis in the future.
---------------------------------------------------------
Title: Astronomy and Space Science in the European Print Media
Authors: Madsen, C.
2003ASSL..290...67M Altcode: 2003asco.book...67M
No abstract at ADS
---------------------------------------------------------
Title: Astronomy Communication
Authors: Heck, A.; Madsen, C.
2003ASSL..290.....H Altcode: 2003asco.book.....H
Astronomers communicate all the time, with colleagues of course, but
also with managers and administrators, with decision makers and takers,
with social representatives, with the news media, and with the society
at large. Education is naturally part of the process. Astronomy
communication must take into account several specificities: the
astronomy community is rather compact and well organized world-wide;
astronomy has penetrated the general public remarkably well with an
extensive network of associations and organizations of aficionados all
over the world. Also, as a result of the huge amount of data accumulated
and by necessity for their extensive international collaborations,
astronomers have pioneered the development of distributed resources,
electronic communications and networks coupled to advanced methodologies
and technologies, often much before they become of common world-wide
usage. This book is filling up a gap in the astronomy-related literature
by providing a set of chapters not only of direct interest to astronomy
communication, but also well beyond it. The experts contributing
to this book have done their best to write in a way understandable
to readers not necessarily hyperspecialized in astronomy nor in
communication techniques while providing specific detailed information,
as well as plenty of pointers and bibliographic elements. This book
will be very useful for researchers, teachers, editors, publishers,
librarians, computer scientists, sociologists of science, research
planners and strategists, project managers, public-relations officers,
plus those in charge of astronomy-related organizations, as well
as for students aiming at a career in astronomy or related space
science. <P />Link: <A href="http://www.wkap.nl/prod/b/1-4020-1345-0">
http://www.wkap.nl/prod/b/1-4020-1345-0</A>
---------------------------------------------------------
Title: Public Communication of Astronomy
Authors: Madsen, C.; West, R. M.
2003ASSL..290....3M Altcode: 2003asco.book....3M
No abstract at ADS
---------------------------------------------------------
Title: Breaking the ground for the European research area - The
conference "European research 2002"
Authors: Madsen, C.
2002Msngr.110...46M Altcode:
In the days November 11-13, about 9000 scientists, science
administrators and policy makers gathered in Brussels to attend the
Launch Conference for the ‘6th Framework Programme of the European
Community for research, technological development and demonstration
activities' - or for short, ‘FP-6'. While most participants came
from the member states of the European Union, candidate countries and
associated states, the meeting was in fact attended by people from
65 countries, demonstrating the wide scope and the importance of the
process set in motion to create the European Research Area. Some 50
TV teams and 230 journalists from the print media covered the event,
which El País, the leading Spanish newspaper, described as ‘The
Science Summit in Brussels'. The strong media interest bears witness to
the fact that science and technology (and with them, also education)
are playing an increasingly important and visible role in the public
sphere and that the organization and execution of research, as well
as the exploitation of scientific results, are assuming importance in
the mainstream political debate.
---------------------------------------------------------
Title: Celebrating ESO's 40th anniversary
Authors: Madsen, C.
2002Msngr.110...45M Altcode:
ESO has always been a forwardlooking organization, focussed on present
and future programmes and projects. In its 40th year, this is as true
as ever, as ESO keeps its eyes on implementing the VLTI, initiating the
development of the second-generation instrumentation for the VLT and,
of course, embarking on Phase II of the ALMA project, for which the ESO
Council gave the green light at its midyear meeting in London. Still, a
40th anniversary warrants a look at the decades passed and a reflection
on the role and achievements of the organization during a period of
time in which our science has progressed tremendously. That ESO has
achieved its goals is undisputed, providing evidence of the wisdom of
those astronomers who gathered in Leiden in early 1954 to formulate
the need for this organization and justifying the trust displayed by
the five countries, which were the original signatories to the 1962
convention that formed the legal base for ESO.
---------------------------------------------------------
Title: Forty years ESO - public anniversary activities
Authors: Madsen, C.
2002Msngr.109...56M Altcode:
Readers of The Messenger will be well aware of ESO's 40th anniversary in
October this year. This is most certainly a reason for ESO's friends to
celebrate. Beyond the professional astronomers, engineers and other
people with direct links to the organization, this includes many
people all over Europe, e.g. amateur astronomers, science teachers,
and people with a general interest in science. At the same time,
the European Intergovernmental Research Organizations constitute fine
examples of how, through collaboration, European countries can interact
and achieve ambitious goals. Thus the success of ESO reaches beyond
the confines of professional Astronomy.
---------------------------------------------------------
Title: ESO in the European Parliament
Authors: Madsen, C.
2002Msngr.108...43M Altcode:
Astronomy and Astrophysics is not normally at the centre of attention
at the highest political circles in Europe. However, the renaissance
that our science is currently experiencing, not least based on the
spectacular success of the VLT, has not gone unnoticed among the
decision makers in Europe.
---------------------------------------------------------
Title: ESO Presentation in Brussels
Authors: Madsen, C.
2001Msngr.106...48M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Latest News: ESO High-Level Presentation in Porto
Authors: Madsen, C.
2001Msngr.104...21M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Success for “Physics on Stage” Festival in Geneva
Authors: Madsen, C.; West, R.
2000Msngr.102...29M Altcode:
Can you imagine how much physics is in a simple match of ping-pong,
in throwing a boomerang, or in a musical concert? Physics is all
around us and governs our lives. But who is going to maintain these
technologies and develop new ones in the future? Recent surveys show
a frightening decline of interest in physics and technology among E
u r o p e 's citizens, especially school children. Fewer and fewer
young people enrol in physics courses at Europe's universities while
scepticism towards science and technology is spreading and causing
great concern among governments and educators.
---------------------------------------------------------
Title: Public outreach in astronomy: The ESO experience
Authors: Madsen, C.; West, R. M.
2000ASSL..250...25M Altcode: 2000iha..conf...25M
No abstract at ADS
---------------------------------------------------------
Title: Science with the Atacama Millimetre Array
Authors: Madsen, C.
1999Msngr..98...56M Altcode:
Science with the Atacama Large Millimetre Array
---------------------------------------------------------
Title: ESO at the Hannover Fair
Authors: Madsen, C.
1999Msngr..96...29M Altcode:
The Hannover Fair is the world's largest industrial fair. Each year
more than 300,000 visitors from all over the world attend this major
event which occupies 30 large exhibition halls. This year, about 7300
enterprises from 63 countries demonstrated their latest products
and services, either at individual stands or within ‘national'
information stands.
---------------------------------------------------------
Title: Award for the ESO VLT Project
Authors: Madsen, C.
1998Msngr..94...38M Altcode:
Naturally, ‘First Light' for the first of the VLT Unit Telescopes
has not gone unnoticed by the astronomical community. However, also
newspapers, magazines, radio and TV have reported widely about this
new facility and about the first, fascinating pictures that were
obtained with UT1. Another sign of the world-wide attention that the
VLT has caught was the fact that the well-known US magazine Popular
Science chose the project for one of the coveted “The Best of What's
New Awards” for 1998, given to the 100 most important technology
developments in the course of the year. The construction of the VLT was
recognised as an “outstanding achievement” within the “Aviation
and Space” category.
---------------------------------------------------------
Title: Sea & Space - A Successful Educational Project for Europe's
Secondary Schools
Authors: Madsen, C.; West, R.
1998Msngr..93...44M Altcode:
There are many links between the Sea and the Space surrounding
us. Indeed, Space itself is often likened with a new and uncharted
Ocean on which we now continue the great voyages of discovery of the
past. Space-based satellites allow us to study the processes in the
Earth's oceans in unprecedented detail and at the same time to verify
complex principles in fundamental sciences like physics, chemistry and
mathematics. Space is also our tenuous link to the distant places from
where the ingredients of life first came to our planet, and the ocean
is where they began the incredible evolutionary processes of which we
ourselves are a product.
---------------------------------------------------------
Title: Astronomy On-Line - the World's Biggest Astronomy Event on
the World-Wide-Web
Authors: Albrecht, R.; West, R.; Naumann, M.; Madsen, C.
1998ASPC..145..248A Altcode: 1998adass...7..248A
This educational programme was organised in a collaboration between
ESO, the European Association for Astronomy Education (EAAE) and the
European Union (EU) during the 4th European Week for Scientific and
Technological Culture. Astronomy On-Line brought together about 5000
students from all over Europe and other continents. Learning to use
the vast resources of tomorrow's communication technology, they also
experienced the excitement of real-time scientific adventure and the
virtues of international collaboration.
---------------------------------------------------------
Title: ESO at the Leipzig fair
Authors: Madsen, C.
1997Msngr..89...13M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: The astronomy on-line project.
Authors: West, R.; Madsen, C.
1997Msngr..87...51W Altcode:
A major Web-based educational programme, known as Astronomy On-Line,
has just taken place in close collaboration between the European
Association for Astronomy Education (EAAE), the European Southern
Observatory and the European Union.
---------------------------------------------------------
Title: The King of Sweden Visits ESO Exhibition
Authors: Madsen, C.
1996Msngr..84...36M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: ESO Exhibition in Florence
Authors: Madsen, C.
1993Msngr..72...10M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: ESO at CNRS Plenary Meeting
Authors: Madsen, C.
1993Msngr..72...12M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: "Exploring the Universe" from the Desert Gate
Authors: Madsen, C.
1992Msngr..70...24M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: ESO exhibitions in Chile - a tremendous success.
Authors: Bouchet, P.; Cabillic, A.; Madsen, C.
1992Msngr..68...18B Altcode:
No abstract at ADS
---------------------------------------------------------
Title: ESO at Expo '92
Authors: Madsen, C.
1992Msngr..67...48M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Impressions from the XXI IAU General Assembly.
Authors: Baade, D.; Merkle, F.; Traat, P.; Sterken, C.; Grosbøl,
P.; Rosa, M.; Madsen, C.; Warmels, R.; van der Laan, H.
1991Msngr..65...17B Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Planeta Terra - Nosso Destino Comum
Authors: Madsen, C.
1991Msngr..64...60M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: NGC 5084: a massive disc galaxy with a tilted ring.
Authors: Zeilinger, W. W.; Galletta, G.; Madsen, C.
1990MNRAS.246..324Z Altcode:
Spectroscopic and photometric observations of the edge-on galaxy NGC
5084 are presented and discussed. The galaxy exhibits a very faint outer
structure which is is almost straight in projection, but is tilted by
~5^deg^ with respect to the brighter, inner stellar disc. Stellar and
gas rotation curves at different position angles are presented, as well
as accurate CCD surface photometry in Gunn i waveband. A geometrical
analysis of the galaxy component is conducted on PDS tracings from ESO
and ESO/SRC Sky Atlas copies. It is suggested that the tilt between
the above components is due to the warping of the main galaxy plane,
with the gas confined to a ring occupying its outer edge. If this is
so, the apparent misalignment is only due to the lack of matter at
intermediate radii. A three-component galaxy model has been used to
correct the stellar rotation curve for the effects of integration along
the line-of-sight and asymmetric drift. The resulting curve is in good
agreement with the H I results in the outer parts. From this model, a 3D
mass and light distribution has been derived and hence the mass-to-light
ratio at various radii. This ratio varies from ~19 M_sun_/L_sun_ in
the inner disc, up to ~45 M_sun_/L_sun_ in the outskirts, and there
is a possible central peak with M/L > 30 M_sun_/L_sun_. A massive,
dark halo is required to explain the galaxy dynamics, which place NGC
5084 among the supermassive disc galaxies. The presence of this dark
halo offers a mechanism that could stabilize the warped disc. The
possible external origin of the warped disc is discussed.
---------------------------------------------------------
Title: BBC Makes ESO Film
Authors: Madsen, C.
1990Msngr..59...20M Altcode:
BBC Makes ESO Film
---------------------------------------------------------
Title: ESO at World Tech Vienna
Authors: Madsen, C.
1989Msngr..57...33M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Signposts of low mass star formation in molecular clouds.
Authors: Reipurth, B.; Madsen, C.
1989Msngr..55...32R Altcode:
Regions of massive star formation are easily recognizable because
of the presence of bright, often very extended H11 regions. The more
quiescent places where only low mass star formation takes place are
not so immediately obvious to identify. Most of the low mass star
forming regions known today were found in the 1950's, mainly through
objective prism surveys for Ha emission stars done by Joy, Herbig,
Haro and others. Their results are summarized and supplemented by
later findings in a new catalogue by Herbig and Bell (1988), which
Iists 742 mainly low mass pre-main-sequence stars. Another recent
and rich source of low mass young stars is the IRAS catalogue. IRAS
data towards clouds, however, often suffer from source confusion and,
in particular, extraction problems because of background emission.
---------------------------------------------------------
Title: The Changing of Skyline of La Silla
Authors: Madsen, C.
1989Msngr..55...31M Altcode: 1989Msngr..55...31.
The Changing of Skyline of La Silla
---------------------------------------------------------
Title: Book-Review - Exploring the Southern Sky
Authors: Laustsen, S.; Madsen, C.; West, R. M.; Kutyrev, A. S.
1988SvA....32..695L Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas
from the European Southern Observatory
Authors: Laustsen, S.; Madsen, C.; West, R. M.; Glass, I. S.
1988MNSSA..47...58L Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas
from the European Southern Observatory
Authors: Laustsen, S.; Madsen, C.; West, R. M.; Bhatt, H. C.
1988BASI...16..136L Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas
from the European Southern Observatory
Authors: Laustsen, S.; Madsen, C.; West, R. M.
1988Sci...239Q1437L Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas
from the European Southern Observatory / ESO
Authors: Laustsen, S.; Madsen, C.; West, R. M.; Mitton, J.
1988JBAA...98..114L Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Book-Review - Atlas of the Southern Hemisphere
Authors: Laustsen, S.; Madsen, C.; West, R. M.; Oleak, H.
1988AN....309..345L Altcode:
No abstract at ADS
---------------------------------------------------------
Title: A Deep High Resolution Wide Field Survey of the Milky Way
(With 1 Figures)
Authors: Madsen, C.
1988astr.conf..210M Altcode:
Generally speaking, objects in the Milky Way are probably the most
observed astronomical objects. To obtain an overview of the Milky Way
band, wide angle photography becomes necessary. Consequently a number
of observers have produced wide angle photographs or full panoramas
by making mosaics from several photographs. Most of the published
photographs of the Milky Way band or parts thereof have been obtained
in narrow pass-bands, such as Hα.
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Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas
from the European-Southern
Authors: Laustsen, S.; Madsen, C.; West, R. M.; Morrison, P.
1988SciAm.258a.104L Altcode: 1988SciAm.258..104L
No abstract at ADS
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Title: Deep LMC Images
Authors: West, R. M.; Pedersen, H.; Madsen, C.
1987Msngr..50...24W Altcode:
One of the most observed objects in the southern sky is the Large
Magellanic Cloud. It is easily seen as a naked-eye object near the
southern celestial pole together with its less conspicuous neighbour,
the Small Magellanic Cloud. Looking at the LMG, the casual observer
discerns the elongated bar and the bright 30 Doradus nebula and,
since February this year, the famous Supernova 1987 A.
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Title: Book-Review - Exploring the Southern Sky
Authors: Laustsen, S.; Madsen, C.; West, R. M.; Hughes, D. W.
1987Natur.330..618L Altcode:
No abstract at ADS
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Title: Supernova 1987A in the Large Magellanic Cloud
Authors: West, R. M.; Madsen, C.; Bahcall, J.; Dar, A.; Piran, T.;
Murdin, P.; Beresford, T.
1987IAUC.4329....2W Altcode: 1987IAUC.4329....1W; 1987IAUC.4329....0W
R. M. West, European Southern Observatory, informs us that a color
exposure (Agfachrome 1000 RS, Hasselblad 6 x 6) of the LMC was made by
C. Madsen at La Silla during Feb. 23.042-23.056 UT. Sanduleak -69 202 is
just seen near the limiting magnitude of about 12. J. Bahcall, A. Dar
and T. Piran, Institute for Advanced Study, Princeton, communicate
the following note, prepared in advance of the report of the neutrino
detection on IAUC 4323: "We have calculated the event rate expected in
terrestrial neutrino detectors from neutrinos produced in the formation
of the neutron star in the LMC supernova. Using neutrino fluxes from a
model stellar collapse calculation of Wilson et al. and cross sections
from Bahcall, we estimate that only about one atom of Ar is produced in
the Davis Cl tank, but that about 50 electron recoils, with energies of
about 10 MeV, are produced in the Kamiokande II water detector. We also
estimate about 3 events each in the scintillators of the University of
Pennsylvania (Homestake Mine) and the Italian- Russian collaboration
(Mont Blanc). The results are sensitive to the effective temperature of
the emitted neutrino spectrum." P. Murdin, Royal Greenwich Observatory,
reports: "It is not clear whether the relative constancy of the light
curve of SN 1987A from Feb. 25 to Mar. 3 represents the maximum in a
typical type II light curve or the 20 day premaximum halt seen in SN
1940B and 1941A. If SN 1987A follows precedent, either it will decline
soon to mag 6, where it will remain in the post-maximum plateau until
early May, or it will brighten in mid-March to a maximum at mag about
2, remaining brighter than mag 6 until early July. Observers should be
aware of this uncertainty when planning observations." Visual magnitude
estimate by T. Beresford, Adelaide, South Australia: Mar. 3.42 UT, 4.3.
---------------------------------------------------------
Title: Wide angle photography of the Milky Way.
Authors: Madsen, C.; Laustsen, S.
1986Msngr..46...12M Altcode:
Since astronomers began to use photography on a scientific basis,
a number of pictures of the Milky Way band, or large parts thereof,
has been made. Barnard (1890, 1927) produced a series of fine Milky
Way photos. Later attempts by Rodgers, Whiteoak et al. (1960),
Schmidt-Kaler and Schlosser (1972), Sivan (1974) and others resulted
in impressive pictures, either in the form of panoramas or extreme
wide-field views, mostly in weil defined (narrow) spectral bands. The
most famous depietion of the Milky Way, however, is not a photograph
but a drawing made by hand. This was made by M. and T. Keskula at
Lund Observatory, and it has become the standard representation of
the Milky Way band in textbooks.
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Title: Some nonatlas work at the European Southern Observatory (ESO)
Sky Atlas Laboratory
Authors: Madsen, C.
1984asph.conf..143M Altcode: 1984asph.rept..143M
Black and white and color astronomical photography at the European
Southern Observatory is described. For black and white copying, unsharp
masking, diffuse light amplification (DLA), and integrated printing
are used. To reduce noise in DLA plate surfaces, several enhanced
derivatives are printed together. Color photographs are produced by
contact printing. The application of false color composites for fast
location of excess UV objects is described.
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Title: Some non-atlas work at ESO Sky Atlas Laboratory.
Authors: Madsen, C.
1984ORROE..14..143M Altcode:
The ESO Sky Atlas Laboratory (SAL) was set up in 1972 with the aim
of producing the ESO Quick Blue Survey and later the joint ESO/SERC
Survey of the Southern Sky. With the establishment of a Scientific
Group, it became apparent that ESO had additional photographic needs,
the fullfilment of which was also entrusted to SAL. Thus, in the course
of the years, the "Photographic Section" evolved as a subdivision of
the Sky Atlas Laboratory.
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Title: Technical photography at ESO Sky Atlas Laboratory.
Authors: West, R. M.; Diebold, L.; Dumoulin, B.; Madsen, C.; Québatte,
J.; Völk, E.; Zodet, H.
1984ESOTR..14.....W Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Moderne photographische Kopiermethoden in der Astronomie
Authors: Madsen, C.
1984MitAG..62..175M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Tirage en couleur de photographies astronomiques à
l'Observatoire Européen Austral.
Authors: Madsen, C.; Tarenghi, M.
1983LAstr..97..376M Altcode:
No abstract at ADS
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Title: A Dust lane in NGC 6251.
Authors: Nieto, J. -L.; Coupinot, G.; Lelievre, G.; Madsen, C.
1983MNRAS.203P..39N Altcode:
A dust lane cutting the central region of the radio galaxy NGC 6251
along its minor axis has been observed. This dust lane is roughly
parallel to the radio jet. The implications of this observation are
discussed: (1) NGC 6251 resembles a prolate object, morphologically
at least. (2) Since the jet is remarkably linear, the configuration
of the dust lane-stellar potential-nucleus system is probably quite
stable. The dust lane may be responsible for the bending of the jet
outwards. (3) Time-scale arguments relative to a possible merging
suggest a rather slow non-relativistic motion. (4) The orientation of
the dust lane does not support the suggestion by Kotanyi & Ekers of
a correlation between the axis of rotation of the gaseous disc and the
jet axis in a radio galaxy, or of a correlation between the alignment
of both rotation and jet axes with the power of the source.
---------------------------------------------------------
Title: Fotografisk arbejde hos ESO.
Authors: Madsen, C.
1983ATi....16..109M Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Astronomical Color Printing at ESO
Authors: Madsen, C.; Tarenghi, M.
1982Msngr..30...15M Altcode:
When the photographic labs in the new Garching Headquarters were
planned, the installation of a colour lab was also foreseen. Following
the removal from Geneva, a market survey of available colour equipment
was carried out, leading to the purchase of a Durst 1800 Laborator
enlarger featuring a CLS 2000 colour head and a negative carrier able
to accommodate 25 x 25 cm originals, an Autopan 40-60 C processing
machine and various equipment for process control.
---------------------------------------------------------
Title: On the reality of minor planet (330) Adalberta
Authors: West, R. M.; Madsen, C.; Schmadel, L. D.
1982A&A...110..198W Altcode:
It is argued that the minor planet (330) Adalberta, as discovered
photographically by Wolf in 1892, is nonexistent. It appears that the
two positions of the planet refer to galactic stars which, mainly due
to differences in the limiting magnitudes of the plates, simulated
a moving object. It is proposed that (330) Adalberta be deleted from
the minor planet list.
---------------------------------------------------------
Title: Photographic Image Manipulation
Authors: Madsen, C.
1982Msngr..28...19M Altcode:
The Messenger No. 25 contained a short, general description of
the non-atlas work being done in the Sky Atlas Laboratory. Briefly
mentioned in the article were contrast manipulating methods ranging
from masking-to reduce the contrast of a picture--to contrast enhancing
methods used to obtain printable negatives (or positives). Here the
procedure, the advantages and the problems connected with masking and
image amplification, will be described in some detail.
---------------------------------------------------------
Title: (330) Adalberta
Authors: West, R. M.; Madsen, C.; Schmadel, L. D.; Wolf, M.
1982IAUC.3672....2W Altcode:
R. M. West and C. Madsen, European Southern Observatory; and
L. D. Schmadel, Astronomisches Rechen-Institut, inform us that this
notorious minor planet, allegedly observed by M. Wolf on two nights
only in 1892 March, does not exist. A careful reexamination of the
original Heidelberg plates shows that Wolf's two measurements refer
to galactic stars.
---------------------------------------------------------
Title: Non-Atlas Photographic Work in the ESO Sky Atlas Laboratory
Authors: Madsen, C.
1981Msngr..25...16M Altcode:
As is weil known to the readers of the MESSENGER, the ESO Sky Atlas
Laboratory was established to set up and undertake the production of the
ESO/SRC Sky surveys. To fulfil its duties, a number of dark rooms were
set up and, after some years of hard work, techniques were developed
which permit limited mass-production without sacrificing the quality
which has become the hallmark of this project.
