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Author name code: jefferies-john
ADS astronomy entries on 2022-09-14
author:"Jefferies, John T."

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Title: Frank Quimby Orrall (15 October 1925 - 4 February 2000).
Authors: Jefferies, J. T.; Zirker, J. B.
2000SoPh..194..185J    Altcode:
  No abstract at ADS

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Title: A legendary polyglot... and lovely days
Authors: Jefferies, John T.
1998ASSL..222...96J    Altcode: 1998ream.conf...96J
  No abstract at ADS

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Title: A Stochastic Model of the Solar Atmosphere
Authors: Gu, Yeming; Jefferies, John T.; Lindsey, Charles; Avrett,
   E. H.
1997ApJ...484..960G    Altcode:
  We present a model for the lower solar atmosphere based on continuum
  observations of the Sun spanning the 2-1200 μm wavelength range. We
  have shown that the data, in particular the center-to-limb brightness
  profiles at 50-350 μm, cannot be accounted for by any model which
  is plane-parallel and homogeneous in the height range in which this
  radiation is formed. We accordingly set out to develop a two-component
  model as the natural generalization. Making use of a theory for
  radiation transfer in a stochastic multi-component atmosphere, we find
  that one can indeed obtain an inhomogeneous model which satisfies
  center-to-limb data over the 2-1200 μm range. This composite model
  is made up of hot “flux tubes” randomly embedded in a cool medium,
  the flux tubes expanding to occupy an increasing proportion of the
  atmosphere as we move up in height. <P />The cool ambient component
  shows a monotonic decrease in temperature in the range defined by the
  data. The temperature in the hot component is constant at about 6500 K
  up to about 400 km and increases monotonically above that height. The
  center-to-limb observations demand that the gas in the interiors of
  the flux tubes be recessed downward with respect to a hydrostatic
  equilibrium distribution of density. This appears to constitute a
  chromospheric Wilson depression consistent with a magnetic field
  of about 120 G in the flux-tube interior at a height of about 600
  km. <P />The new model is shown to be consistent with other spectral
  measurements independent of those used to define it. It gives a
  very good fit to the 0.5 μm continuum intensities across the disk,
  and provides an excellent accounting for the disk-center brightness
  temperature in the center of the 3-2 R14 CO line at 4.667 μm. A
  boundary temperature of less than about 3000 K in the cold component
  is suggested from the limb-darkening data available for this line. <P
  />In an appendix we mention a procedure for an analogous study based on
  the intensities of multiplet lines, which may hold promise for modeling
  over a wider range of heights that can be spanned by the IR data.

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Title: Radiative Transfer in Stochastic Media
Authors: Gu, Yeming; Lindsey, Charles; Jefferies, John T.
1995ApJ...450..318G    Altcode:
  We review some basic concepts arising in the study of radiative
  transfer in a stochastic atmosphere and consider their application
  to realistic atmospheric models. In particular, we examine the theory
  of Lindsey and Jefferies which deals with multicomponent atmospheres
  whose stochastic nature is entailed in the morphology of a network of
  boundaries separating different atmospheric components. This theory
  is based on the Markov assumption, that the probability, per unit path
  length along a ray, for transition into another component 15 independent
  of the distance already traveled in the current component. We examine
  the applicability of the theory to models that are non-Markovian,
  paying particular attention to the assignment of transition rates
  of such atmospheres. We consider in detail transition probabilities
  for spherical, tubular, conical, and other fluted structures, and
  show how the effects of overlap are to be incorporated for the case
  of a two-component atmosphere. Comparisons of results obtained from
  the theory of Lindsey and Jefferies with those found from Monte Carlo
  calculations, for models based on identical structures randomly embedded
  into an ambient medium, show that the Markov assumption promises to
  be a good approximation for the determination of the statistics of
  radiative transfer in a wide variety of stochastic atmospheres, even
  when they are markedly non-Markovian.

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Title: Infrared Applications for Radiative Transport in Stochastic
    Media
Authors: Lindsey, C.; Gu, Y.; Jefferies, J. T.
1995itsa.conf..313L    Altcode:
  No abstract at ADS

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Title: Radiative Transfer in Stochastic Atmospheres
Authors: Gu, Y.; Lindsey, C.; Jefferies, J. T.
1994AAS...185.0702G    Altcode: 1994BAAS...26Q1316G
  We describe a general statistical perspective for the study of
  radiative transfer through inhomogeneous media and apply it to
  simple stochastic atmospheric models. The particular context for our
  applications considers a stochastic atmosphere to be a multi-component
  medium in which any individual component of the medium is locally
  smooth. The stochastic nature of the atmosphere resides in the
  statistical character of the complex network of boundaries that
  separate various species of media one from another. We illustrate the
  theory with simple atmospheric models based on an ambient medium into
  which are randomly embedded structural elements containing alternative
  species of medium. We consider structures of various shapes and sizes,
  ranging from simple spheres to elongated or fluted structures with
  preferred orientation. An important distinctive quality of a stochastic
  atmosphere is whether the medium contains structures that individually
  may be optically thick. Atmospheres containing only optically thin
  structures tend to be statistically amenable to representation by
  equivalent smooth atmospheres. The theory we have developed is fully
  applicable to atmospheres that contain optically thick elements as
  well as optically thin ones. Such conditions apply to a broad variety
  of radiative transfer problems in astrophysics and stellar physics,
  for example, to emission from interstellar gas clouds, from solar
  or stellar chromospheres or from photospheres that contain heated
  magnetic flux tubes. In this work we concentrate on a formalism that
  rests on the Markov assumption, which states that the probability of
  encountering a transition from one type of medium, A, to another,
  B, is independent of the cumulative distance since the transition
  into medium A, as one proceeds along the optical path. We examine the
  importance of this assumption and its utility as a first approximation
  by illustrating the consequences of its application to atmospheric
  models that are non-Markovian.

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Title: Overview of Infrared Solar Physics
Authors: Jefferies, J. T.
1994IAUS..154....1J    Altcode:
  No abstract at ADS

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Title: Infrared solar physics: proceedings of the 154th Symposium
    of the International Astronomical Union, held in Tucson, Arizona,
    U.S.A., March 2-6, 1992.
Authors: Rabin, D. M.; Jefferies, John T.; Lindsey, C.
1994IAUS..154.....R    Altcode:
  No abstract at ADS

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Title: An active solar prominence in 1.3 MM radiation
Authors: Harrison, R. A.; Carter, M. K.; Clark, T. A.; Lindsey, C.;
   Jefferies, J. T.; Sime, D. G.; Watt, G.; Roellig, T. L.; Becklin,
   E. E.; Naylor, D. A.; Tompkins, G. J.; Braun, D.
1993A&A...274L...9H    Altcode:
  We present new millimetre-wavelength observations of an active solar
  prominence. Observations made over a two-day period with the James
  Clerk Maxwell Telescope on Manna Kea, Hawaii, give a unique view in
  1.3 mm radiation of the spectacular prominence that appeared on the
  west solar limb in the total solar eclipse of 11 July 1991.

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Title: Measurement of the Height of the Solar CO Layer During the
    11 July 1991 Eclipse
Authors: Clark, T. A.; Naylor, D. A.; Tompkins, G. J.; Lindsey, C. A.;
   Becklin, E. E.; Jefferies, J. T.; Harrison, R. A.; Roellig, T. L.;
   Carter, M.; Braun, D. C.; Watt, G.
1992AAS...181.8108C    Altcode: 1992BAAS...24.1253C
  No abstract at ADS

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Title: Extreme-infrared brightness profile of the solar chromosphere
    obtained during the total eclipse of 1991
Authors: Lindsey, C.; Jefferies, J. T.; Clark, T. A.; Harrison, R. A.;
   Carter, M. K.; Watt, G.; Becklin, E. E.; Roellig, T. L.; Braun, D. C.;
   Naylor, D. A.
1992Natur.358..308L    Altcode:
  THE solar chromosphere is a thin layer of gas that is several thousand
  degrees hotter than the underlying photosphere, and responsible for
  most of the Sun's ultraviolet emission. The mechanism by which it is
  heated to temperatures exceeding 10,000 K is not understood. Millimetre
  and submillimetre radiometry can be used to obtain the chromospheric
  temperature profile, but the diffraction-limited resolution for the
  largest telescopes is at best 17 arcsec, or ~12,500 km at the Sun's
  distance. This is greater than the thickness of the quiet chromosphere
  itself. The total eclipse of July 1991, which passed over the Mauna
  Kea Observatory in Hawaii, provided a rare opportunity to make limb
  occultation observations with a large submillimetrewavelength telescope,
  the 15-m James Clerk Maxwell Telescope, and in this way we obtained a
  temperature profile in 1.3-mm radiation with ~300 km resolution at the
  Sun. Our observations indicate that spicules (magnetically entrained
  funnels of gas) reach a temperature of 8,000 K at 3,000-4,000 km above
  the photosphere, a temperature lower than those of many spicule models.

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Title: Chromospheric Dynamics Based on Infrared Solar Brightness
    Variations
Authors: Kopp, G.; Lindsey, C.; Roellig, T. L.; Werner, M. W.; Becklin,
   E. E.; Orrall, F. Q.; Jefferies, J. T.
1992ApJ...388..203K    Altcode:
  The NASA Kuiper Airborne Observatory was used to observe far-infrared
  continuum brightness fluctuations in the lower chromosphere due to
  solar 5 minute oscillations on the quiet sun. Brightness measurements
  made at 50, 100, 200, and 400 microns show a strong correlation with
  visible-line Doppler measurements from photospheric and chromospheric
  altitudes. The motion of the chromosphere is nearly in phase over a
  large range of heights, while the infrared brightness lags the Doppler
  velocity by phases varying from significantly less than 90 deg at low
  altitudes to nearly 90 deg at higher altitudes. It is proposed that
  this is the result of a nonadiabatic response of the chromospheric
  gas to compression and may indicate an important mechanism for wave
  dissipation. Thermal relaxation times ranging from about 40 s at
  340 km above the tau(5000) = 1 photosphere to about 300 s at 600 km
  are proposed.

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Title: The Solar Chromospheric Supergranular Network in 850 Micron
    Radiation
Authors: Lindsey, Charles A.; Jefferies, John T.
1991ApJ...383..443L    Altcode:
  The first submillimeter solar observations are examined of the
  chromospheric supergranular network, made on the 15-m James Clerk
  Maxwell Telescope on Mauna Kea in 850-micron radiation. These
  observations are useful for thermal diagnostics of the low and middle
  chromospheres of the quiet-sun and magnetic regions, where mechanical
  heating of the atmospheric medium first becomes manifest. The models
  of Vernazza, Avrett and Loeser appear to be consistent with these
  observations.

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Title: Submillimeter Solar Limb Profiles Determined from Observations
    of the Total Solar Eclipse of 1988 March 18
Authors: Roellig, T. L.; Becklin, E. E.; Jefferies, J. T.; Kopp,
   G. A.; Lindsey, C. A.; Orrall, F. Q.; Werner, M. W.
1991ApJ...381..288R    Altcode:
  Observations were made of the extreme solar limb in six far-infrared
  wavelength bands ranging from 30 to 670 micron using the Kuiper
  Airborne Observatory during the total eclipse of the sun on 1988 March
  18. By observations of the occultation of the solar limb by the moon,
  it was possible to obtain a spatial resolution of 0.5 arcsec normal
  to the limb. The solar limb was found to be extended with respect
  to the visible limb at all of these wavelengths, with the extension
  increasing with wavelength. Limb brightening was observed to increase
  slightly with increasing wavelength, and no sign of a sharp emission
  spike at the extreme limb was found at any of these wavelengths. The
  observations can be well fitted by a chromospheric model incorporating
  cool dense spicules in the lower chromosphere.

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Title: The Solar MG i Spectrum from ATMOS. I. Identification and
    Preliminary Discussion
Authors: Jefferies, John T.
1991ApJ...377..337J    Altcode:
  As an initial step in a program to understand some puzzling aspects of
  the infrared solar Mg I spectrum, the set of high-resolution, high SNR
  lines of this spectrum are examined in the 1985 ATMOS experiment on
  Spacelab 3. Wavenumbers were obtained for the Mg I transitions lying
  in or near the range covered by ATMOS, namely 650 to 4800/cm. Lines
  involving principal quantum numbers up to n = 10 are seen in the data;
  some striking features of the Mg I spectrum are described and some
  directions of interest for future analytical studies and for future
  flights of the experiment are indicated.

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Title: On the Inference of Magnetic Field Vectors from Stokes Profiles
Authors: Jefferies, John T.; Mickey, Donald L.
1991ApJ...372..694J    Altcode:
  A study is made of the range of applicability of the weak-field
  approximation for the inference of magnetic field vectors from the
  profiles of the Stokes parameters. It is shown that, for typical solar
  lines in the visible, this approximation may be applied with an accuracy
  of 20 percent for field strengths as great as 3500/gL G (where gL is
  the Lande factor) in the line wings. A systematic underestimate of
  the field strength seems to occur for strong fields - observations in
  several related spectral lines may allow a calibration of this effect,
  and so for an increase in accuracy of the inferences. The procedures
  have been tested using solar data obtained in two lines of Fe I, near
  6300 A, with the Stokes Polarimeter at the Mees Solar Observatory of
  the University of Hawaii.

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Title: Physics of the infrared spectrum.
Authors: Deming, Drake; Jennings, Donald E.; Jefferies, John; Lindsey,
   Charles
1991sia..book..933D    Altcode:
  The authors describe the diagnostic value and principal results
  derived from solar studies at wavelengths exceeding 1.6 μm. The
  infrared is a favorable region to conduct studies of the solar
  magnetic field. The high-n emission lines in the 12-μm spectrum are
  of special interest. However, the LTE or NLTE nature of the lines,
  and the mechanism of their excitation, remain poorly understood. The
  far-infrared continuum is an excellent thermometer for the upper
  photosphere and chromosphere, allowing study of the average thermal
  state and the compressional effects of wave motions. Observations
  of limb brightening at far-infrared wavelengths have shown that the
  structure of the chromosphere is spatially inhomogeneous, even at
  the lowest chromospheric altitudes. Time-series observations in the
  far-infrared show that the chromosphere exhibits a substantial thermal
  response to the 5-min oscillations. Further progress in far-infrared
  studies will result from the new generation of large-aperture
  submillimeter telescopes, and from the development of the theory of
  radiative transfer in inhomogeneous media.

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Title: Direct inference of magnetic field vectors from Stokes
    profiles.
Authors: Jefferies, J. T.; Mickey, D. L.
1991sopo.work..373J    Altcode:
  No abstract at ADS

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Title: Submillimeter Observations of the Sun from the James Clerk
    Maxwell Telescope
Authors: Lindsey, Charles A.; Yee, Selwyn; Roellig, Thomas L.; Hills,
   Richard; Brock, David; Duncan, William; Watt, Graeme; Webster, Adrian;
   Jefferies, John T.
1990ApJ...353L..53L    Altcode:
  The first submillimeter solar observations from the 15 m James
  Clerk Maxwell Telescope (JCMT) on Mauna Kea are reported. The JCMT
  submillimeter heterodyne receiver is used to observe the sun in 850
  micron radiation. These are the first submillimeter observations of
  features on the size scale of the chromospheric supergranular network
  and of sunspots. A comparison is made between 850 micron images and
  calcium K line images of the chromospheric supergranular network in
  the quiet sun and in plage. Images of sunspots are given, noting that
  their 850 micron brightness is comparable to, or somewhat greater than,
  that of the quiet sun.

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Title: Far-Infrared Intensity Variations Caused by 5 Minute
    Oscillations
Authors: Lindsey, C.; Kopp, G.; Becklin, E. E.; Roellig, T.; Werner,
   M. W.; Jefferies, J. T.; Orrall, F. Q.; Braun, D.; Mickey, D. L.
1990ApJ...350..475L    Altcode:
  Observations of solar IR intensity variations at 50, 100, and
  200 microns were made simultaneously and cospatially with Doppler
  measurements in the sodium D1 line at 5896 A. Brightness temperature
  variations of several K in amplitude are highly correlated with five
  minute Doppler oscillations. The brightness variations are attributed
  to work done on the chromospheric medium by compression, driven by the
  five minute oscillations. The Doppler oscillations lead the brightness
  variations by about 47 deg in phase at 50 and 100 microns and by about
  72 deg in phase at 200 microns.

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Title: Statistical Concepts in Radiative Transfer through
    Inhomogeneous Media
Authors: Lindsey, C.; Jefferies, J. T.
1990ApJ...349..286L    Altcode:
  The theory of radiative transfer in inhomogeneous media is extended
  to handle transfer for scale lengths small compared to the scale
  size of the inhomogeneity. This is called the microscopic domain of
  inhomogeneous radiative transfer. A concept called the vector intensity
  distribution is introduced to characterize the statistical properties
  of radiation in various species of medium. Radiative transfer in an
  inhomogeneous atmosphere is expressed in terms of the evolution of
  this vector intensity distribution and its various moments along the
  optical path.

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Title: Transfer of Line Radiation in a Magnetic Field
Authors: Jefferies, John; Lites, Bruce W.; Skumanich, A.
1989ApJ...343..920J    Altcode:
  Using a classical approach, the transfer equations are derived for
  spectral-line radiation in a medium which is permeated by a magnetic
  field. Consideration is given to solutions of these equations for
  the 'weak-field' case, when the Zeeman splitting is a fraction of
  the Doppler width, and the range of validity of such solutions. Some
  approximate expressions allow a simple inference of the vector-field
  characteristics directly from the line profiles.

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Title: Profiles of the Extreme Solar Limb at Far Infrared and
    Submillimeter Wavelengths
Authors: Roellig, T. L.; Werner, M. W.; Kopp, G.; Becklin, E. E.;
   Lindsey, C.; Orrall, F. Q.; Jefferies, J. T.
1989BAAS...21..765R    Altcode:
  No abstract at ADS

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Title: Radiative Transfer in Inhomogeneous Atmospheres: A Statistical
    Approach
Authors: Jefferies, John T.; Lindsey, Charles A.
1988ApJ...335..372J    Altcode:
  A procedure is presented for calculating the statistical properties
  of the radiation which emerges from a multicomponent gas when the
  absorption and emission coefficients vary statistically along the
  direction of propagation. A relation describing the evolution of
  the intensity distribution through the gas is derived, and, from
  that, a transfer equation for the expected value of the intensity is
  obtained which is analogous to the standard transfer equation for a
  continuous medium and to which it reduces in the limit of a homogeneous
  medium. General solutions for this transfer equation, and the analogous
  transfer equation for the variance, are found for a special class of
  situations. As a representative example, consideration is given to
  the transfer of radiation through a spherical atmosphere consisting of
  radial structures, with an exponential height distribution, which are
  immersed according to a given probability distribution in an ambium,
  itself inhomogeneous, whose properties also vary with height.

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Title: Submillimeter Observations of the Extreme Solar Limb by
    Occultation in the Total Solar Eclipse of 18 March 1988
Authors: Roellig, T. R.; Werner, M. W.; Kopp, G.; Becklin, E. E.;
   Lindsey, C.; Orrall, F. Q.; Jefferies, J. T.
1988BAAS...20..689R    Altcode:
  No abstract at ADS

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Title: Modeling the Solar Chromosphere by Airborne Solar Eclipse
    Observations
Authors: Orrall, F. Q.; Becklin, E. E.; Lindsey, C.; Roellig, T. R.;
   Werner, M. W.; Kopp, G.; Jefferies, J. T.
1987BAAS...19.1014O    Altcode:
  No abstract at ADS

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Title: Observations of Far-Infrared Solar Continuum Variations Due
    to Compression Waves
Authors: Lindsey, C.; Becklin, E. E.; Orrall, F. Q.; Werner, M. W.;
   Roellig, T. R.; Kopp, G.; Jefferies, J. T.
1987BAAS...19S1014L    Altcode:
  No abstract at ADS

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Title: Extreme Limb Profiles of the Sun at Far-Infrared and
    Submillimeter Wavelengths
Authors: Lindsey, C.; Becklin, E. E.; Orrall, F. Q.; Werner, M. W.;
   Jefferies, J. T.; Gatley, I.
1986ApJ...308..448L    Altcode:
  Thirty, 50, 100, and 200 microns solar limb intensity profiles
  determined with arcsecond resolution from airborne observations of
  the occultation of the solar limb during the total eclipse of July
  31, 1981, are presented. Two points of particular importance emerge:
  (1) the longer-wavelength (100 and 200 micron) limbs are significantly
  brighter than disk center. At 200 microns the extreme limb is about 1.22
  times the brightness of disk center. This is consistent with the 6000 K
  temperature-plateau structure of the model chromospheres of Vernazza,
  Avrett, and Loeser (1973, Ap. J., 184, 605; 1981; Ap. J. Suppl., 45,
  635); and (2) the longer wavelength limbs are extended significantly
  further above the visible limb than Vernazza, Avrett, and Loeser
  predict. These results provide a strong basis for modeling of the solar
  chromosphere free from the assumption of gravitational-hydrostatic
  equilibrium.

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Title: Extreme limb profiles of the sun at far-infrared and
    submillimeter wavelengths
Authors: Lindsey, C.; Becklin, E. E.; Orrall, F. Q.; Werner, M. W.;
   Jefferies, J. T.; Gatley, I.
1986STIN...8632375L    Altcode:
  Thirty, 50, 100, and 200 microns solar limb intensity profiles
  determined with arcsecond resolution from airborne observations of
  the occultation of the solar limb during the total eclipse of 1981
  July 31 are presented. Two points of particular importance emerge:
  (1) the longer-wavelength (100 and 200 micron) limbs are significantly
  brighter than disk center. At 200 microns the extreme limb is about 1.22
  times the brightness of disk center. This is consistent with the 6000 K
  temperature-plateau structure of the model chromospheres of Vernazza,
  Avrett, and Loeser (1973, Ap. J., 184, 605; 1981; Ap. J. Suppl., 45,
  635;) and (2) the longer wavelength limbs are extended significantly
  further above the visible limb than Vernazza, Avrett, and Loeser
  predict. These results provide a strong basis for modeling of the solar
  chromosphere free from the assumption of gravitational-hydrostatic
  equilibrium.

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Title: The SHIRSOG Workshop. Proceedings of a workshop on prospects
    for a new synoptic high resolution spectroscopic observing facility,
    held at the National Solar Observatory, National Optical Astronomy
    Observatories, Tucson, Arizona, USA, 3 September 1986.
Authors: Giampapa, M. S.; Jefferies, J. T.; Linsky, J. L.
1986swpw.book.....G    Altcode:
  No abstract at ADS

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Title: Extreme limb profiles of the sun at far infrared and
    submillimeter wavelengths.
Authors: Becklin, E. E.; Lindsey, C.; Orrall, F. Q.; Jefferies, J. T.;
   Werner, M.; Gatley, I.
1985NASCP2353...58B    Altcode:
  The authors present results of analysis of 30 to 200 μm observations
  of the occultation of the solar limb during the total solar eclipse
  of 1981 July 31. The observations were made from the Kuiper Airborne
  Observatory. The 30 to 200 μm continuum radiation from the solar
  limb originates in the lower and middle chromosphere. By measuring the
  brightness profiles, one is able to fix important constraints on both
  the temperature of the material and its density structure.

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Title: Extreme limb profiles of the Sun at far infrared and
    submillimeter wavelengths
Authors: Becklin, E. E.; Lindsey, C.; Orrall, F. Q.; Jefferies, J. T.;
   Werner, M. W.; Gatley, I.
1984abas.symp...58B    Altcode:
  Limb intensity profiles at 30, 50, 100, and 200 microns, determined
  from Kuiper airborne observatory (KAO) observations of the occultation
  of the solar limb during the total eclipse of July 31, 1981, are
  presented. Significant but gradual limb brightening was found at the
  longer wavelengths consistent with the 6000 K temperature-plateau
  structure of the model chromospheres of Vernazza, Avrett, and
  Loeser. The 100 and 200 micrometers limbs are extended significantly
  further above the visible limb than the Vernazza, Avrett, and Loeser
  model predicts. These results show that the solar chromosphere is
  strongly perturbed from gravitational-hydrostatic equilibrium to heights
  as low as 1000 km. These profiles can serve as a powerful diagnostic
  for modeling the temperature and density of chromospheric structure
  free from the assumption of gravitational-hydrostatic equilibrium.

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Title: Extreme Limb Profiles of the Sun at Far Infrared and
    Submillimeter Wavelengths
Authors: Lindsey, C.; Becklin, E. E.; Orrall, F. Q.; Werner, M. W.;
   Jefferies, J. T.; Gatley, I.
1984BAAS...16..992L    Altcode:
  No abstract at ADS

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Title: In Memoriam: R. G. Giovanelli
Authors: Jefferies, John T.
1984SoPh...94....1J    Altcode:
  No abstract at ADS

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Title: Observations of the brightness profile of the sun in the
    30-200 micron continuum
Authors: Lindsey, C.; Becklin, E. E.; Jefferies, J. T.; Orrall, F. Q.;
   Werner, M. W.; Gatley, I.
1984ApJ...281..862L    Altcode:
  The authors observed the brightness profile of the quiet Sun in
  broad continuum passbands centered at 30, 50, 100, and 200 μm with
  a resolution of 2arcmin. Weak radial darkening was seen at all four
  wavelengths near disk center. This reverses to brightening toward the
  limb in the 100 and 200 μm continuum. Radial darkening at 100 and
  200 μm is not expected from smooth model chromospheres consistent
  with absolute brightness measurements. These results do not support
  a homogeneous model of the low chromosphere, where the temperature
  reversal occurs.

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Title: Coronal and chromospheric physics
Authors: Jefferies, J. T.; Landman, D. A.; Orrall, F. Q.
1983huha.rept.....J    Altcode:
  Achievements and completed results are discussed for investigations
  covering solar activity during the solar maximum mission and the solar
  maximum year; other studies of solar activity and variability; infrared
  and submillimeter photometry; solar-related atomic physics; coronal
  and transition region studies; prominence research; chromospheric
  research in quiet and active regions; solar dynamics; eclipse studies;
  and polarimetry and magnetic field measurements. Contributions were
  also made in defining the photometric filterograph instrument for the
  solar optical telescope, designing the combined filter spectrograph,
  and in expressing the scientific aims and implementation of the solar
  corona diagnostic mission.

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Title: Submillimeter extensions of the solar limb determined from
    observations of the total eclipse of 1981 July 31
Authors: Lindsey, C.; Becklin, E. E.; Jefferies, J. T.; Orrall, F. Q.;
   Werner, M. W.; Gatley, I.
1983ApJ...264L..25L    Altcode:
  The authors present first results of observations of a lunar occultation
  of the solar limb made from the Kuiper Airborne Observatory in the
  30, 50, 100, and 200 μm continuum during the total solar eclipse
  of 1981 July 31. The solar limb is found to be extended at the
  longer wavelengths up to 1000 km higher than predicted from smooth
  plane-parallel chromospheric models. Results at both second and third
  contact show the infrared limb extensions to be approximately 0arcsec.8,
  1arcsec.5, 2arcsec.5, and 3arcsec.0 above the visible limb in the 30,
  50, 100, and 200 μm bands, respectively.

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Title: Submillimeter extensions of the solar limb determined from
    observations of the total eclipse of 1981 July 31
Authors: Lindsey, C.; Becklin, E. E.; Jefferies, J. T.; Orrall, F. Q.;
   Werner, M. W.; Gatley, I.
1982STIN...8314047L    Altcode:
  First results are presented of observations of a lunar occultation
  of the solar limb made from the Kuiper Airborne Observatory in the
  30 micrometr, 50 micrometer, 100 micrometer, and 200 micrometer
  continuum during the total solar eclipse of 1981 July 31. The solar
  limb was extended at the longer wavelengths up to 1000 km higher than
  predicted from smooth plane-parallel chromospheric models. Results at
  both second and third contact show the infrared limb extensions to
  be approximately 0".8, 1"5, 2".5 and 3".0 above the visible limb in
  the observed bands, respectively. A possible interpretation proposes
  chromospheric fine structure inhomogeneities of greater density than
  presently incorporated in models of the middle chromosphere.

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Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii 96822. Report.
Authors: Jefferies, J. T.
1982BAAS...14..177J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Astronomical studies of the major planets, natural satellites
    and asteroids using the 2.24 M telescope
Authors: Jefferies, J. T.
1982huha.reptR....J    Altcode:
  Ground based detection of east-west asymmetries in the Jovian torus,
  three dimensional models of the plasma conditions in the Jovian torus,
  rotational variations in methane band images of Neptune, Io's rapid
  flickering, thermophysical models, the diameters and albedos of the
  satellites of Uranus from radiometric observations, the diameters of
  Pluto and Triton, standard stars are discussed.

---------------------------------------------------------
Title: Research in planetary astronomy and operation of Mauna Kea
    Observatory
Authors: Jefferies, J. T.
1982huha.reptS....J    Altcode:
  Highlights of the programs including the major planets, satellites,
  asteroids, and comets are presented. The operation of the 2.24 m
  telescope is discussed.

---------------------------------------------------------
Title: Astronomical studies of the major planets, natural satellites
    and asteroids using the 2.24 M telescope
Authors: Jefferies, J. T.
1982huha.reptQ....J    Altcode:
  Directional features in the Jovian sodium torus, high quality CCD
  images of the major planets, methane bands in the spectrum of Triton,
  the central wavelength of the SO2 absorption band on Io, a component
  on the icy surfaces of the satellites of Uranus, fluctuation of Io's
  volcanic radiation, standard stars, and thermal radiation from the
  four brightest satellites of Uranus are discussed.

---------------------------------------------------------
Title: Submillimeter observations of solar limb-brightening in the
    total solar eclipse of 31 July 1981
Authors: Becklin, E. E.; Jefferies, J. T.; Lindsey, C.; Orrall, F.;
   Gatley, I.; Werner, M.
1981huha.rept.....B    Altcode:
  Eight flights of the Kuiper Airborne Observatory (KAO) were devoted to
  solar observation. The successful observation of a total solar eclipse
  was accomplished. The observations were made simultaneously at 30,
  50, 100, and 200 microns. The successful adaptation of the KAO for
  solar observations thus provided the most detailed data to date in
  this spectral band. The results from a preliminary analysis of the KAO
  data are summarized: (1) the 200 micron limb is extended about 3 arc
  sec above the 30 micron limb, indicating the prescence of cool dense
  material up to the altitudes of spicules; (2) strong radial darkening
  of the quiet sun intensity profile appeared at 200 microns, probably an
  indication that hot material in the low chromosphere is recessed into
  vertical magnetic flux tubes embedded in a cooler nonmagnetic substrate,
  which obscures the heated material approaching the limb; (3) active
  regions were observed to undergo a strong increase in contrast above the
  quiet sun background at wave lengths of 100 microns and longer; and (4)
  the moon was mapped for use as a photometric standard for determining
  the absolute intensity of the sun in all four wavelength bands.

---------------------------------------------------------
Title: Submillimeter Continuum Observations of Solar Plages
Authors: Jefferies, J. T.; Becklin, E. E.; Lindsey, C.; Orrall, F. Q.;
   Gatley, I.; Werner, M.
1981BAAS...13Q.881J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Observations of the Center-to-Limb Intensity of the Quiet
    Sun at 30-200 μm
Authors: Orrall, F. Q.; Becklin, E. E.; Jefferies, J. T.; Lindsey,
   C.; Gatley, I.; Werner, M.
1981BAAS...13..880O    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Submillimeter Observations of the Extreme Solar Limb Obtained
    in the Total Eclipse of 1981 July 31
Authors: Lindsey, C.; Becklin, E. E.; Jefferies, J. T.; Orrall, F. Q.;
   Gatley, I.; Werner, M.
1981BAAS...13..880L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A Comprehensive Study of the Sun in the Submillimeter Continuum
Authors: Becklin, E. E.; Jefferies, J. T.; Lindsey, C.; Orrall, F. Q.;
   Gatley, I.; Werner, M.
1981BAAS...13..880B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Institute for Astronomy, University of Hawaii, Honolulu,
    Hawaii 96822. Report.
Authors: Jefferies, J. T.
1981BAAS...13..177J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hawaii, University-Of
Authors: Jefferies, J. T.
1980BAAS...12..117J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Ca II emission from stellar chromospheres.
Authors: Cram, L. E.; Krikorian, R.; Jefferies, J. T.
1979A&A....71...14C    Altcode:
  Measurements are presented of the separations of the K2 peaks and
  the K1 dips of the emission core of the Ca II K line observed on
  high-dispersion spectra of 33 late-type stars. These separations
  (called W1 and W2) are compared with the emission core width W which
  satisfies the Wilson-Bappu correlation. With some qualifications, it
  is found that W is directly proportional to the 1.3 power of W1 and
  the 1.06 power of W2. Some consequences of this result are discussed.

---------------------------------------------------------
Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii 96822. Report.
Authors: Jefferies, J. T.
1979BAAS...11..115J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Requests for Observing Time on the CFHT
Authors: Locke, J. L.; Jefferies, J. T.
1979BCFHT...2....3L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii. Observatory report.
Authors: Jefferies, J. T.
1977BAAS....9..106J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: High resolution atlas of the solar spectrum 2678-2931 A
Authors: Allen, M. S.; McAllister, H. C.; Jefferies, J. T.
1977STIN...7831029A    Altcode:
  A portion of the ultraviolet solar spectrum is presented in this
  high resolution atlas. The data, originating from a rocket echelle
  spectrogram obtained on 19 June 1974 of a quiet area near the center
  of the solar disk, extend from 2678 to 2931 A. The instrument had
  a nominal resolving power of 200,000 at these wavelengths and the
  rms precision of the rectified wavelength scale is 15 mA. Absolute
  intensities are computed by calibration to the absolute measurements
  of Kohl and Parkinson.

---------------------------------------------------------
Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii. Observatory report.
Authors: Jefferies, J. T.
1976BAAS....8...99J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The abundance determination in a stellar atmosphere. I. LTE
    experimentation using an artificial non-LTE spectrum.
Authors: Dumont, S.; Heidmann, N.; Jefferies, J. T.; Pecker, J. -C.
1975A&A....40..127D    Altcode:
  It is shown that the classical LTE analysis of an atomic spectrum
  of a solar-like star leads to values of the abundance (A) which may
  be different from the real values. Various uncertainties affect the
  results derived from neutral lines. However, proper selection of
  the observational data, for instance use of ion lines, can lead, in
  similar cases at least, to good values of A. These conclusions concern
  the solar-like case; however, they emphasize that, in all cases,
  the effect of departures from LTE needs very careful discussion.

---------------------------------------------------------
Title: High-Resolution Solar Spectra in the 2900 A and the 1700
    A Range
Authors: McAllister, Howard C.; Smith, Peter H.; Jefferies, John T.
1975BAAS....7..365M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Linear Polarization of Continuum Radiation in Sunspots
Authors: Finn, G. D.; Jefferies, J. T.
1975BAAS....7..349F    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii. Observatory report.
Authors: Jefferies, J. T.
1975BAAS....7...62J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Polarization of Continuum Radiation in Sunspots. I:
    Rayleigh and Thomson Scattering
Authors: Finn, G. D.; Jefferies, J. T.
1974SoPh...39...91F    Altcode:
  Expressions are derived for the Stokes parameters of light scattered by
  a layer of free electrons and hydrogen atoms in a sunspot. A physically
  reasonable sunspot model was found so that the direction of the
  calculated linear polarization agrees reasonably with observations. The
  magnitude of the calculated values of the linear polarization agrees
  generally with values observed in the continuum at 5830 Å. Circular
  polarization in the continuum also accompanies electron scattering in
  spot regions; however for commonly accepted values of the longitudinal
  magnetic field, the predicted circular polarization is much smaller
  than observed.

---------------------------------------------------------
Title: Fine Structure of the Upper Chromosphere
Authors: Jefferies, J. T.
1974IAUS...56...71J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Non-LTE Profiles of the A1 I Autoionization Lines
Authors: Finn, G. D.; Jefferies, J. T.
1974SoPh...34...57F    Altcode:
  A non-LTE formulation is given for the transfer of radiation in the
  autoionizing lines of neutral aluminum at λ1932 and λ1936 through both
  the Bilderberg and Harvard-Smithsonian model atmospheres. Numerical
  solutions for the common source function of these lines and their
  theoretical line profiles are calculated and compared with the
  corresponding LTE profiles. Our results show that the non-LTE profiles
  provide a better match with the observations. They also indicate that
  the continuous opacity of the standard solar models should be increased
  in this wavelength region if the center-limb variations of observed and
  theoretical profiles of these lines are to be in reasonable agreement.

---------------------------------------------------------
Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii. Observatory report.
Authors: Jefferies, J. T.
1974BAAS....6...48J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Inversion of the Solar Limb-darkening Equation in the Presence
    of Noise
Authors: Kunasz, C. V.; Jefferies, J. T.; White, O. R.
1973A&A....28...15K    Altcode:
  Summary. We discuss the formulation and application of the
  Phillips-Twomey method for inverting the integral equation of solar
  limb darkening in the presence of noise. We show, through numerical
  experiments, that the method can be successfully applied to real data
  and that it has clear advantages over those standard methods that
  rely on the expression of the source function in an analytic form. In
  addition, we briefly discuss some potentially interesting methods
  of a different kind, which are still under examination. Key words:
  solar limb-darkening - Phillips-Twomey inversion - source function

---------------------------------------------------------
Title: Inversion of the Limb Darkening Equation in the Presence
    of Noise
Authors: Kunasz, Chela V.; Jefferies, J. T.; White, O. R.
1973BAAS....5S.274K    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Analysis of Si II Solar UV Emission Lines
Authors: McAllister, H. C.; Jefferies, J. T.
1973BAAS....5T.276M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii. Observatory report for the period July 1971 through June 1972.
Authors: Jefferies, J. T.
1973BAAS....5..120J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Temperature Distribution in a Stellar Atmosphere, Diagnostic
    Basis
Authors: Jefferies, John T.; Morrison, Nancy D.
1973NASSP.317....3J    Altcode: 1973stch.coll....3J; 1973IAUCo..19....3J
  No abstract at ADS

---------------------------------------------------------
Title: Solar activity (Activité solaire).
Authors: Jefferies, J. T.; Simon, P.; Beckers, J. M.; McLean, D. J.
1973IAUTA..15...75J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hawaii's Mauna Kea Observatory Today
Authors: Morrison, David; Jefferies, John T.
1972S&T....44..361M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Interpretation of Total Line Intensities from Optically
Thin Gases. III: Application to Coronal Forbidden Line Spectra
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1972SoPh...22..327J    Altcode:
  The diagnostic method developed in the two preceding papers of this
  series is applied to coronal forbidden line intensity data obtained at
  eclipses in 1952, 1961, 1965, 1966, and 1970. The application of the
  method is limited by the nature of the data but allows a first inference
  of the relationship between electron density and temperature in the
  condensations observed at these eclipses, and of the distribution of
  the electrons within the temperature range samples by the observations
  effectively 10<SUP>6</SUP> to 2.4 × 10<SUP>6</SUP> K. We determine the
  relative abundance of nickel to iron in the corona, finding a value in
  agreement with latest photospheric determinations and with a similar
  (factor of two) uncertainty. We are also able to set lower limits to
  the abundance of iron with respect to hydrogen, again finding values
  consistent with recent photospheric determinations.

---------------------------------------------------------
Title: The Interpretation of Total Line Intensities from Optically
Thin Gases. II: The Coronal Forbidden Lines
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1972SoPh...22..317J    Altcode:
  We discuss the application of a general diagnostic procedure, developed
  in the preceding paper of this series, to the inference of the physical
  state of coronal condensations from a knowledge of their forbidden
  line emission. We consider the limitations set on such an analysis by
  inadequacies in existing data and indicate the additional observations
  in the infrared and ultraviolet, as well as the visible, which will
  be needed for development of the full power of the diagnostic method.

---------------------------------------------------------
Title: The Interpretation of Total Line Intensities from Optically
Thin Gases. I: A General Method
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1972SoPh...22..307J    Altcode:
  We describe a general method for inferring, from the line emission of an
  optically thin medium, the physical state of the gas along the column in
  the line of sight which is sampled by the observations. Since it is not
  possible to infer the distribution of the physical state parameters with
  position in the line of sight - any arbitrary rearrangement of material
  giving equivalent line emission - we seek instead to specify the
  state in another way. A unique specification is found in terms of the
  bivariate distribution function μ (n, T), describing the partitioning
  of the matter in the gas over the density and temperature. We show
  that, given sufficient observational data, it is in principle possible
  to determine both μ (n, T), and the chemical composition. With less
  complete data the acuity of the analysis is correspondingly reduced.

---------------------------------------------------------
Title: University of Hawaii, Institute for Astronomy, Honolulu,
    Hawaii. Observatory report for the period July 1970 through June 1971.
Authors: Jefferies, J. T.
1972BAAS....4...45J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Guest Investigators at the Mauna Kea Observatory
Authors: Jefferies, John T.
1971PASP...83..693J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Population Inversion in the Outer Layers of a Radiating Gas
Authors: Jefferies, J. T.
1971A&A....12..351J    Altcode:
  On the basis of solutions to the coupled radiative transfer equations
  for multiplet lines, we present simple physical arguments on the
  expected distribution of population among closely spaced energy levels
  in the ground, or a low-lying state, of an atom or molecule. It is
  shown that, because uncoupling of multiplet lines will occur in the
  outer layers of a radiating gas, population "anomalies" will occur in
  the fine structure states associated with the upper and/or lower levels
  of the multiplet transitions. Order of magnitude estimates suggest
  that the mechanism is able to account for some aspects of the 18 cm OH
  emission, though better solutions of the coupled transfer equations
  are needed before proper observational comparison is possible. It is
  suggested that atoms with p and p2 configurations may be expected to
  have inverted populations among the ground state levels in the outer
  layers of an optically thick gas. A list is given of infrared and
  submillimetric atomic lines which may show amplification in astronomical
  sources. Two lines of C T are accessible to ground based (high altitude)
  instrumentation, and these may merit a diligent search. Key words:
  population inversion - radiative transfer

---------------------------------------------------------
Title: The spectrum of the chromosphere and corona from lambda 3000
    to lambda 7000 on March 7, 1970.
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1971BAAS....3Q.262J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Coronal models and coronal chemical abundances.
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1971BAAS....3..261J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Population inversion in the outer layers of radiating gas.
Authors: Jefferies, J. T.
1971JQSRT..11..545J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Spectrum of the Inner Corona Observed during the Total
    Solar Eclipse of 30 May, 1965
Authors: Jefferies, John T.; Orrall, Frank Q.; Zirker, J. B.
1971SoPh...16..103J    Altcode:
  A series of spectrograms of the inner solar corona were obtained at
  the total solar eclipse of 30 May 1965 using a fast spectrograph with
  a circular slit that recorded the spectrum from λ3000 to λ9000 at all
  position angles around the limb simultaneously. In this paper absolute
  intensity is given as a function of position angle for the stronger
  lines and the continuum. In the coronal enhancement or condensation
  centered at heliocentric position angle 293°, absolute intensity is
  given for 34 forbidden emission lines and the continuum.

---------------------------------------------------------
Title: Formation of Line Spectra—A Review
Authors: Jefferies, J. T.
1970PASA....1..356J    Altcode: 1970PASAu...1..356J
  A typical stellar spectrogram shows a vast number of spectral
  lines. Each of these has its characteristic shape and strength which
  must, in some way, reflect the structure of the atmosphere in which the
  radiation arose. It seems reasonable that from all this profile data we
  should be able (and with considerable redundancy) to infer a good deal
  about the physical structure of the radiating gas, and a major effort
  has correspondingly been devoted to clarifying the physical basis of
  spectral line formation, i.e., exactly how the atmospheric structure
  and the atomic properties are reflected in the line profiles. This
  problem, however, is far from solved : Few, if any, of the profiles
  of strong lines can be predicted in detail from model atmospheres,
  nor have analyses of the profiles yielded unambiguous data on the
  atmospheric structure. Indeed, as recently as 1967, the participants
  at a conference in Bilderberg (Holland) concluded that no data at
  all which had been obtained from line profile analyses was worthy of
  inclusion in specifying the solar atmospheric model. Evidently, then,
  the problem of line formation is not trivial ; in this paper we discuss
  some of the difficulties and review the not inconsiderable progress
  which has been made in this area of astrophysical research.

---------------------------------------------------------
Title: Institute for Astronomy, University of Hawaii, Honolulu,
    Hawaii. Report 1968-1969.
Authors: Jefferies, J. T.
1970BAAS....2...49J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Models for Coronal Condensations
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1969BAAS....1Q.246J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: 22. Eission Line Spectrum of the Solar Corona
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1969LIACo..15..235J    Altcode: 1969MSRSL..17..235J
  No abstract at ADS

---------------------------------------------------------
Title: 21. Forbidden Lines in the Solar Corona, Introductory Report
Authors: Jefferies, J. T.
1969LIACo..15..213J    Altcode: 1969MSRSL..17..213J
  No abstract at ADS

---------------------------------------------------------
Title: Emission line spectrum of the solar corona.
Authors: Jefferies, J. T.; Orrall, F. Q.; Zirker, J. B.
1969MSRSL..25..235J    Altcode: 1969tisa.conf..235J
  No abstract at ADS

---------------------------------------------------------
Title: Forbidden lines in the solar corona.
Authors: Jefferies, J. T.
1969MSRSL..25..213J    Altcode: 1969tisa.conf..213J
  No abstract at ADS

---------------------------------------------------------
Title: Studies in spectral line formation. III. Non-linear multi-level
    atom problems.
Authors: Finn, G. D.; Jefferies, J. T.
1969JQSRT...9..469F    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Stellar aerodynamics. Introductory remarks.
Authors: Jefferies, J. T.
1969JQSRT...9..191J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Progress at Mauna Kea Observatory
Authors: Jefferies, John T.; Sinton, William M.
1968S&T....36..140J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Chromospheric Spectrum at the 1962 Eclipse
Authors: Dunn, R. B.; Evans, J. W.; Jefferies, J. T.; Orrall, F. Q.;
   White, O. R.; Zirker, J. B.
1968ApJS...15..275D    Altcode:
  A joint expedition of the High Altitude Observatory, Sacramento Peak
  Observatory, and the National Bureau of Standards obtained slitless
  spectrograms of the flash spectrum at the February 5,1962, total eclipse
  of the Sun. The spectrograms covered the wavelength range of about
  3200 to 9100 A with a height resolution of 100 km. The spectrographic
  equipment, the observations, the photometric calibration procedures,
  and the methods adopted to reduce the large quantity of data are
  described. The results are presented in a set of tables that show the
  wavelength and identification (where known) of each of the 3500 lines
  recorded. A separate set of tables lists the intensity of each line at
  each height. The latter tables are ordered according to the element,
  ionization stage, and multiplet number associated with the line.

---------------------------------------------------------
Title: Formation and Analysis of Line Spectra-A Review of Some
    Recent Progress.
Authors: Jefferies, John T.
1968AJS....73R..65J    Altcode:
  Within the past five years substantial progress has been made in the
  self- consistent (or non-LTE) theory of line formation. The current
  situation is reviewed, and outstanding questions raised, both in the
  "analytical" problem of deriving an atmospheric structure from an
  observed line spectrum, and in the "synthetic" problem of computing the
  spectrum emitted by a gas of given physical properties. The emphasis
  throughout is on the physical meaning of the results rather than on the
  mathematical problems. A brief discussion of basic principles is given
  to illustrate the fundamental role played by the score function. The
  successes and shortcomings of the work of the 1950's is then briefly
  summarized. A major limitation in earlier work lay in its restriction
  to a two-level atom which was, in turn, associated with numerical
  difficulties encountered in the solution of two-point boundary value
  problems or, equivalently in this case, of the integral equations for
  the line source functions. The different methods developed to overcome
  these problems will be sketched and some representative results given
  for some multilevel configurations. The physical interpretation of
  the results will be stressed, especially as concerns the predicted
  relationships between the different spectral line profiles arising
  from a given configuration of levels. On this basis the concepts of
  thermalization length and net-radiative bracket are examined. The
  analysis of an observed spectrum introduces different but related
  problems. It is shown how predictions from the self-consistent
  theory of line formation can be applied to allow a solution of the
  analytical problem and how and why this analysis differs from the LTE
  case. Limitations to the general analytical procedure are outlined.

---------------------------------------------------------
Title: Spectral line formation
Authors: Jefferies, John T.
1968slf..book.....J    Altcode: 1968QB465.J4.......
  No abstract at ADS

---------------------------------------------------------
Title: The Analysis of Spectral-Line Profiles. I. a. Generalized
    Theory for the Solar Case
Authors: Jefferies, J. T.; White, O. R.
1967ApJ...150.1051J    Altcode:
  Recent studies of spectral-line formation are shown to provide a basis
  for the analysis of profiles of multiplet lines in the "solar case," i
  e., when limb-darkening data are available. The theoretical foundation
  is more general than that assuming local thermodynamic equilibrium,
  which is included as a special case. A detailed analytical procedure
  is given along with a discussion of its shortcomings and limitations.

---------------------------------------------------------
Title: The Analysis of Spectral-Line Profiles. II. an Application
    to the Solar Sodium D-Lines
Authors: Curtis, G. W.; Jefferies, J. T.
1967ApJ...150.1061C    Altcode:
  On the basis of general principles set down in the first paper of this
  series, an analysis is made of Waddell's solar D-line observations
  The results show a large measure of seff-consistency and, among
  other conclusions, suggest that the temperature minimum in the solar
  atmosphere lies above T5 10- , and that to a factor of order 2 the
  solar abundance of sodium is that given by LTE analyses.

---------------------------------------------------------
Title: The Solar Observatory of the University of Hawaii
Authors: Jefferies, J. T.
1967SoPh....2..369J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Inference of Velocities from Line Asymmetries
Authors: Kulander, John L.; Jefferies, John T.
1966ApJ...146..194K    Altcode:
  Synthetic line profiles are generated for a variety of model atmospheres
  containing linear and quadratic velocity fields. Both weak and strong
  lines are considered. Comparison of the actual velocity structures with
  those inferred from the bisector shifts of the asymmetrical profiles
  show qualitative agreement only in the line cores and in general only
  for velocities small compared with the thermal velocity. Approximate
  expressions relating the observed profile parameters to atmospheric
  velocity parameters, for small linear velocities, are obtained and
  tested. Observed rms displacements in the solar Ha line are used to
  infer the amplitude of the oscillatory velocity field in that region
  of the solar chromosphere where the core is formed.

---------------------------------------------------------
Title: Loop Prominences and Coronal Condensations. III. The Abundances
    of Iron and Calcium
Authors: Jefferies, J. T.; Orrall, F. Q.
1966ApJ...145..231J    Altcode:
  Measured total intensities of the continuum and of the red, green,
  and yellow forbidden coronal lines emitted by discrete features of a
  sporadic coronal condensation are shown to yield firm lower limits to
  the abundances of iron and calcium. These strict lower limits exceed
  the photospheric abundances (derived by curve-of-growth analysis of
  Fraunhofer lines) by a factor of 3 for iron and 12 for calcium; the
  actual coronal abundance will be higher still.

---------------------------------------------------------
Title: Eclipse Determination of Chemical Abundances in the Solar
    Corona.
Authors: Curtis, G. W.; Jefferies, J. T.; Orrall, F. Q.
1966AJ.....71S.382C    Altcode:
  Chemical abundance determinations from observations of the coronal
  emission spectrum (particularly for iron) have consistently exceeded
  those determined from curve of growth analyses of photospheric
  absorption lines. Although the coronal abundances are somewhat
  uncertain because they depend on uncertain coronal models and uncertain
  theories of coronal ionization and excitation, Jefferies and Orrall
  (Astrophy. J. 1966, to be published) have shown that it is possible
  to set rigorous lower limits to the abundances that are insensitive to
  these uncertainties. Applying this method to coronagraph observations
  of the red, yellow, and green coronal lines they found lower limits
  to the calcium and iron abundances in excess of the photospheric
  values by factors of 2 or 3. We have applied this method to the very
  complete observations of the coronal spectrum between A3000 and A9000
  obtained by the University of Hawaii- Sacramento Peak Observatory
  expedition to observe the eclipse of 30 May 1965. Emission lines
  arising from 15 different ions were studied. The resulting lower
  limits to the coronal abundances are given below, along with the photo
  spheric abundances taken from the careful curve of growth studies by
  C. R. Cowley (Astrophys. J. 143, 352, 1966) for Ni, and E. A. Mu~ller
  and J. P. Mutschlecner (Astrophys. J. Suppl. 9, No. 85, 1964) for the
  remainder of the elements. Abundance per 106 protons Element V Cr Mn
  Fe Co Ni Corona (lower limit) 0.22 1.0 0.042 5.0 1.1 1.1 Photosphere
  0.013 0.12 0.065 5.0 0.026 0.49 The coronal abundances shown are
  strict lower limits. The actual values can be that low only if there
  is a specially favorable temperature distribution to make ionization a
  maximum and only if the local electron density is high enough that the
  excitation is governed completely by collisions. But within the ions Fe
  XI and Ni XIII, which give rise to two observable emission lines, it is
  clear that both radiation and collision processes enter to determine
  the degree of excitation. We conclude that the coronal abundances are
  higher than the lower limits shown and that they therefore exceed the
  photospheric values.

---------------------------------------------------------
Title: The Solar Abundance of Iron
Authors: Jefferies, J. T.
1966IAUS...26..207J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Survey of the Problem
Authors: Jefferies, J. T.
1965SAOSR.174....3J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Multilevel Problems
Authors: Jefferies, J. T.
1965SAOSR.174..177J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Loop Prominences and Coronal Condensations. I. Non-Thermal
    Velocities Within Loop Prominences.
Authors: Jefferies, J. T.; Orrall, F. Q.
1965ApJ...141..505J    Altcode:
  Profiles of the Ha-line observed in loop prominences at the limb with
  the coronagraph show much more extended wings than ordinary prominences,
  and a detailed study of the profiles of the loop system of February
  19, 1962, shows that these wings are caused neither by instrumental
  effects nor by the Stark effect but arise from non-thermal motions of
  emitting hydrogen atoms. The possibility that these fast neutral atoms
  were produced by charge exchange or recombination from equally fast
  protons is considered and rejected since the particles would produce
  far too much heating. It is shown, however, that the observed wings
  could reasonably be interpreted as a jetlike streaming, along the loops,
  of matter accelerated from a region near their tops.

---------------------------------------------------------
Title: Loop Prominences and Coronal Condensations. II. The Source
    of Mass and Energy and a Model of the Loop Prominence Mechanism.
Authors: Jefferies, J. T.; Orrall, F. Q.
1965ApJ...141..519J    Altcode:
  Estimates of the mass and energy requirements of loop prominences
  indicate difficulties in the generally accepted "condensation
  process." An alternative process is considered in which super thermal
  particles drift or are injected into the magnetic field of the loop. It
  is found that all the mass required to maintain a loop (or quiescent)
  prominence can be supplied in the form of particles moving at tO cm/sec
  and that their energy will then just balance that lost by radiation
  Since it is now known that loop prominences are associated with those
  flares that produce copious amounts of fast plasma, it is suggested
  that the loops arise naturally as a coronal configuration by which
  this flare plasma is returned to the chromosphere The mass and energy
  required to feed the loop are provided by the injection into the system
  of fast particles of this plasma. The applicability of this mechanism
  to other types of prominences is discussed.

---------------------------------------------------------
Title: The Theory of the Chromospheric Spectrum
Authors: Jefferies, John T.
1965ASSL....1..131J    Altcode: 1965sosp.conf..131J
  No abstract at ADS

---------------------------------------------------------
Title: Solar Flares and the Loop Prominence Mechanism
Authors: Jefferies, J. T.; Orrall, F. Q.
1964NASSP..50...71J    Altcode: 1964psf..conf...71J
  No abstract at ADS

---------------------------------------------------------
Title: On the Interpretation of Prominence Spectra.VI. Temperature
    Determination and a Model for Quiescent Prominences.
Authors: Jefferies, J. T.; Orrall, F. Q.
1963ApJ...137.1232J    Altcode:
  Temperatures estimated from the widths of Balmer lines and from the
  continuum intensities of q prominence emission have previously been
  shown to be discordant. In this paper we show how the crepancy can
  be accounted for in terms of a variable temperature model, and we
  derive the characterisi of such a model. In particular, we show that,
  to account for the observed emission, we can allow onl comparatively
  small amount of material in the line of sight to be at temperatures
  above 15000 K

---------------------------------------------------------
Title: The Structure of Regions of Coronal-Line Emission.
Authors: Jefferies, J. T.; Pecker, C. W.; Thomas, R. N.
1962ApJ...135..653J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: On the Interpretation of Prominence Spectra. V. The Emission
    Lines in Quiescent Prominences.
Authors: Jefferies, J. T.; Orrall, F. Q.
1962ApJ...135..109J    Altcode:
  Observations are presented of emission-line total intensities and
  widths in the range XX for two quiescent prominences. In one of these
  prominences, total intensities are also given for emission lines
  in the range XX . From the total intensities it is found that (1)
  the excitation temperature describing the populations of the energy
  levels of Fe 1 is 3600 K; (2) the ratio of intensity of the 0 1 lines
  at X 7775 and X 8446 (known to be variable in astronomical sources)
  is 18(3) the electron kinetic temperature of the region emitting He
  1 must be greater than 11000 K Estimates are made of the theoretical
  strengths of one line of He 1 and five lines of Fe 1. The shapes of the
  lines in the range XX 3600- 3800 are Gaussian to within the limit of
  error of measurement except for the higher Balmer lines of H 1 and the
  lines of He 1. These lines are all free from self-absorption. The line
  widths of H i correspond to atom kinetic temperature of about 8200 K,
  but this is an upper limit, since non-thermal motions also broaden
  the lines It is shown that the usual method of employing the widths
  of metal lines to correct for these non-thermal motions overcorrects
  in quiescent prominences, yielding too low a temperature; however,
  the hydrogen and metal line widths are consistent with atom kinetic
  temperatures between 6500 and 8200 K. In Paper IV the electron kinetic
  temperature was found to be 12500 K from continuum measures in one of
  these same prominences. The difference between the temperatures given by
  the two methods cannot be attributed to observational error. Although a
  real difference between the atom and electron kinetic temperatures may
  exist, it is suggested rather that these temperatures are averages over
  steep temperature gradients and the averages are weighted differently
  by the two methods.

---------------------------------------------------------
Title: On the Interpretation of Prominence Spectra.IV. The Balmer
    and Paschen Continua in a Quiet Prominence.
Authors: Jefferies, J. T.; Orrall, F. Q.
1961ApJ...134..747J    Altcode:
  Observations of the Balmer and Paschen continua in a quiet prominence
  are discussed. Their self- consistency is considered and the
  observations analyzed for derivation of mean values of the electron
  temperature and density. A graphical method is given for determining
  these mean values from the magnitude of the Balmer or Paschen jump,
  together with the emission per unit volume in the appropriate freebound
  continuum. It is pointed out that, because of the relatively small
  jump at the series limit, Paschen continuum observations are much
  less useful than those at the Balmer limit The Balmer jump and total
  emission is found to be consistent with the mean values T 12000 K and
  n 8 X 1O . These results are compared with those derived previously in
  the same way, for a flare-type loop, namely, T 15000 K and n, 2 X 1O ,
  and for a chromospheric flare T __ 12000 K and n __ 3 X tO .

---------------------------------------------------------
Title: Vertical Velocities in the Solar Chromosphere
Authors: Giovanelli, R. G.; Jefferies, J. T.
1961AuJPh..14..212G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: On the Interpretation of Prominence Spectra. II. The Line
    and Continuous Spectrum of the Spray-Type Limb Event of March 7, 1959.
Authors: Jefferies, J. T.; Orrall, F. Q.
1961ApJ...133..946J    Altcode:
  The line and continuum emission of a limb flare of March 7, 1959, are
  discussed. An analysis of the continuum emission near the almer limit
  shows that the kinetic temperature of the flare must be considerably
  less than 20000 K in that region where the hydrogen is excited. On
  the assumption that the hydrogen emission is axially symmetric,
  a model is derived for the temperature, electron density, and gas
  pressure as a function of distance from the axis. The temperatures
  so derived are much lower than those obtained from the usual methods
  of line-width analysis, which, it is suggested, are of questionable
  value in application to active limb events.

---------------------------------------------------------
Title: On the Interpretation of Prominence Spectra. III. The Line
    and Continuous Spectrum of a Loop Prominence and Limb Flare.
Authors: Jefferies, J. T.; Orrall, F. Q.
1961ApJ...133..963J    Altcode:
  A detailed photometric study is presented of the line and continuous
  spectrum of the limb flare of June 9, 1959. The electron temperature is
  found to be certainly less than 24000 K in the bright, dense central
  portion of the flare, where the hydrogen lines and continuum are
  excited. The flare occurred as a condensation in an active coronal
  region, yet the temperature is only slightly higher than that observed
  in a spray-type flare that originated at the chromospheric level We
  tentatively suggest temperatures of 10000 and 20000 K, respectively,
  for "cool" and "hot" prominence classes suggested by Zirin and
  Tandberg-Nanssen.

---------------------------------------------------------
Title: A Comment of the NRL Solar Lyman-Alpha Results.
Authors: Jefferies, J. T.; Thomas, R. N.
1961ApJ...133..606J    Altcode:
  Supplementary comments are made on the Morton-Widing analysis of the
  NRL Ly-a observations; they serve to bring into sharper focus its
  relation to current attempts at analysis of self-reversed emission
  cores of collison-dominated lines for gradients of T , for chromospheric
  structure, and for differential structure between quiet sun and plage,
  sunspot and flare regions.

---------------------------------------------------------
Title: Source Function in a Non-Equilibrium Atmosphere.VI. The
    Frequency Dependence of the Source Function for Resonance Line.
Authors: Jefferies, J. T.; White, O. R.
1960ApJ...132..767J    Altcode:
  The frequency dependence of the line source function is investigated
  for the case of pure coherent scattering in the reference frame of
  the atom. It is shown that the thermal redistribution due to Doppler
  effect gives a form of scattering similar to complete redistribution
  in the line core and coherency in the wings. Using a modified form for
  this redistribution and allowing for some residual non-coherency due
  to collisions in the frame of the atom, an algebraic solution of the
  transfer equation is obtained, and emergent line profiles are computed,
  for an isothermal atmosphere. It is shown that the line shape in the
  transition region from line core to wing is strongly influenced by the
  proportion of this residual non-coherency. It is finally suggested that,
  until the strength of collisional perturbations is better understood
  from theoretical or laboratory studies, theoretical work on line
  spectra should adopt complete redistribution in scattering.

---------------------------------------------------------
Title: Source Function in a Non-Fquilibrium Atmosphere. VII. The
    Interlocking Problem.
Authors: Jefferies, J. T.
1960ApJ...132..775J    Altcode:
  A general solution to the equations of statistical equilibrium
  is presented and applied to the problem of determining the
  influence of interlocking on the depth variation of line source
  functions. Approximate uncoupled transfer equations are derived
  for a simple three-level atom, and their quality is tested against
  exact solutions. A discussion is given-exemplified by hydrogen-of
  the influence of coupling for models consisting of larger numbers of
  levels. The general form of the depth variation in the H and K lines
  of Ca ii is shown to be little different from that derived in earlier
  papers of this series where interlocking was neglected. It is shown,
  however, that the strong coupling results in a common a given depth-of
  the H and K line source functions.

---------------------------------------------------------
Title: The Source Function in a Non-Equilibrium
    Atmosphere. V. Character of the Selfreversed Emission FO CA^{+}
    H and K.
Authors: Jefferies, J. T.; Thomas, R. N.
1960ApJ...131..695J    Altcode:
  The methodology of Paper III is applied to delineate the principal
  parameters affecting the characteristics of the self-reversed emission
  cores of Ca+ H and K, in order to clarify whether current discussions
  in terms only of are adequate. We find two additional factors to be
  significant-c and the Te gradient. The factor E provides an effect in
  the correct direction to interpret the Wilson-Bappu effect, but of too
  small a size, subject to a more complete treatment of the region outside
  the Doppler core. The effect of the T6 gradient seems more significant,
  particularly as a basis for interpreting the observed solar variations.

---------------------------------------------------------
Title: Thermally Broadened Stark Profiles of Some High Balmer Lines.
Authors: Jefferies, J. T.
1960ApJ...131..690J    Altcode:
  Results are given of some computations of the thermally broadened Stark
  profiles of the Balmer lines H12, H16, H18, and H26. The calculations
  are made for ion densities and kinetic temperatures likely to be
  of interest in solar prominences and flares. The degree of overlap
  between 1126 and H27 is also computed as a function of ion density
  and mean random atomic velocity.

---------------------------------------------------------
Title: The line and continuous emission observed in two limb flares
Authors: Dunn, R. B.; Jefferies, J. T.; Orrall, F. Q.
1960Obs....80...31D    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Source Function in a Non-Equilibrium Atmosphere. III. The
    Influence of a Chromosphere.
Authors: Jefferies, John T.; Thomas, Richard N.
1959ApJ...129..401J    Altcode:
  We apply the methods developed in the preceding two papers to
  investigate the depth dependence of the source function for resonance
  lines in an atmosphere having a chromospheric distribution of T,
  superposed upon a photospheric one. The derived behavior of SL( )
  for the neutral and ionized metals differs and mimics the observed
  behavior of such lines. The hydrogen Balmer lines should behave like
  the neutral metals, and the predicted behavior agrees with our earlier
  empirical results.

---------------------------------------------------------
Title: The nova outburst: III. The ionization of hydrogen gas by an
    exciting star
Authors: Jefferies, J.; Pottasch, S.
1959AnAp...22..318J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Flare of September 18, 1957.
Authors: Jefferies, J. T.; Smith, E. V. P.; Smith, H. J.
1959ApJ...129..146J    Altcode:
  A set of spectra of the disk flare of September 18,1957, is
  discussed. The spectra, covering simultaneously a wave-length range of
  XX 390() 7200 at a dispersion of 2 A/mm, cover the period through the
  maximum phase. The Balmer lines reached a central intensity in excess of
  three times the neighboring continuum and were at that time exceedingly
  wide. Several helium lines were in emission,including X 4686 of He II,
  as well as the prominent neutral lines. The data indicate that the
  excitation conditions in the visible flare vary rapidly with depth
  and suggest that the flare is merely an extension of a more powerful
  excitation. The Balmer series wing shapes are shown to be compatible
  either with Stark effect or with a particular form of velocity field
  of macroscopic or microscopic motions.

---------------------------------------------------------
Title: The Source Function in a Non-Equilibrium Atmosphere. II. The
    Depth Dependence of the Source Function for Resonance and Strong
    Subordinate Lines.
Authors: Jefferies, John T.; Thomas, Richard N.
1958ApJ...127..667J    Altcode:
  We obtain an algebraic solution for the depth variation of the source
  function 8L (r) for resonance and strong subordinate lines by using the
  Eddington approximation plus the method of discrete ordinates. We show
  that if an observed line profile, produced in an atmosphere with the
  above SL (r), is analyzed under the assumption of local thermodynamic
  equilibrium, an underestimate of T.(r) in the outer atmospheric layer
  results. The derived SL(r) agrees in qualitative behavior with the
  source function found empirically by Athay and Thomas for the early
  Balmer lines of hydrogen.

---------------------------------------------------------
Title: On the Interpretation of Prominence Spectra. I. Balmer Series
    Line Widths.
Authors: Jefferies, J. T.; Orrall, F. Q.
1958ApJ...127..714J    Altcode:
  Line widths, derived from a set of high-dispersion spectra in
  Balmer series Ha-H have been used to show that the assumption of a
  constant-source function for Ha in prominences is not, in general,
  correct. It is pointed out that, with our present ignorance of
  prominence conditions, very little information can be obtained from
  the Ha line alone but that, when coupled with spectra in other Balmer
  lines, the Ha line may possibly provide a basis for inferring the run
  of physical conditions with depth. It is suggested that the common
  procedure of determining a kinetic temperature and turbulence from
  hydrogen and helium lines may also be erroneous.

---------------------------------------------------------
Title: The interpretation of Balmer line profiles in solar
    prominences.
Authors: Jefferies, John T.; Orrall, Frank Q.
1957AJ.....62..143J    Altcode:
  In the past, it has been the usual practice to interpret prominence
  observations on the assumption that the observed radiation is the
  intrinsic radiation of the prominence itself. It has been recently
  pointed out, however, that a major component of the observed
  radiation-at least in Ha should be scattered disk radiation;
  the prominence thus acting as a diffuser as well as an emitter. In
  order to get a better understanding of the process of line formation
  in prominences as well as to obtain a consistent approach to the
  determination of prominence temperatures, high dispersion profiles
  have been obtained of the hydrogen Balmer lines Ha through HE and
  the helium lines X5876 and X447I in prominences showing a minimum
  of internal motions. The prominences were observed, at the limb,
  with the i6-inch coronagraph at Sacramento Peak. Several years ago,
  Conway (1952) and Ellison (1952) observed that Ha prominence line
  profiles could be fitted very well to theoretical profiles computed
  on the assumption of a source function constant in frequency across
  the line and constant in depth in the prominence. The same remarkable
  agreement has been obtained for our observations, except of course,
  for those cases where the Ha line is self-reversed. For subordinate
  lines like these, it is almost certain that the source function is in
  fact frequency independent. The good agreement obtained between the
  observed profiles, and those computed on the assumption of a source
  function constant in depth, however, is probably largely fortuitous. It
  seems that almost any monotonic source function could be fitted by
  one of the family of curves. In any case, the occurrence of double-
  peaked profiles in Ha shows that for this line the assumption is not
  generally valid. In order to test this assumption further, the optical
  depth at the center of the Ha line has been computed from the run of
  widths of the Balmer lines H~ through HE. This method was found to give
  a higher optical depth than that implied by the shape of the Ha line
  using the assumption of a source function constant in depth. It seems
  clear that the usual method of estimating prominence temperatures from
  the Ha profile is very unreliable. Conway, M. 1955, Contr. Dunsink
  Obs. No. 3. Ellison, M. A. 1952, Pub. Royal Obs. Edinburgh I,
  No. 5. Sacramento Peak Observatory, Sunspot, N. Mex.

---------------------------------------------------------
Title: Temperatures and electron densities in flares as derived from
    spectroscopic data
Authors: Jefferies, J. T.
1957MNRAS.117..493J    Altcode:
  It is shown that model ares with electron concentrations and
  temperatures in the ranges 5Xio11-io13cm-3 and io4- .K respectively
  have emissions consistent with the observed hydrogen and helium line
  intensities in solar flare spectra. Some difficulties are shown to
  exist in interpreting the observed great line width of H and a possible
  solution is given.

---------------------------------------------------------
Title: The D<SUB>3</SUB> emission of prominences
Authors: Jefferies, J. T.
1956MNRAS.116..629J    Altcode:
  The computed emission of H and D3 from an isothermal slab model
  prominence is shown to give agreement with observational data of
  Bruck and Moss when the model has helium abundance one fifth that
  of hyd gen, thickness z X I0 km, temperature between X 1o deg. K and
  2.0 X I0 deg. K and electron concentration between 1010 cm-3 to 5 X
  1010 . Some evidence has been found that the higher temperatures are
  generally associated with lower electron concentrations. Comparison of
  the present computations with earlier results obtained by the author
  from an analysis of the contour of the H emission of prominences shows
  that the ratio of the abundances of helium and hydrogen atoms in solar
  prominences lies in the range to 04. As for H , the self emission
  in D3 is generally small compared with the diffusely reflected and
  transmitted component.

---------------------------------------------------------
Title: The High Temperature Excitation of Helium
Authors: Jefferies, J. T.
1955AuJPh...8..335J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Hα emission of prominences
Authors: Jefferies, J. T.
1955MNRAS.115..617J    Altcode:
  It is shown that M radiation from the solar disk is strongly reflected
  by prominences and is an important component of their radiation. An
  analysis of their observed Ha emission at the limb indicates a range
  of kinetic temperatures of about io4 to z X i04 deg. K and electron
  concentrations of about i010 to X 1010 cm-3 for stable prominences. Two
  alternative explanations are given for the double peaked profiles
  of Ha sometimes observed in solar prominences, depending on whether
  scattering is coherent or incoherent.

---------------------------------------------------------
Title: The Emission of Radiation from Model Hydrogen Chromospheres. II
Authors: Jefferies, J. T.; Giovanelli, R. G.
1954AuJPh...7..574J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Albedo for the Atomic Scattering of Optical Radiation
Authors: Giovanelli, R. G.; Jefferies, J. T.
1954AuJPh...7..570G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Some Electron Collision Cross Sections of CaII
Authors: Jefferies, J. T.
1954AuJPh...7...22J    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Emission of Radiation from Model Hydrogen Chromospheres
Authors: Jefferies, J. T.
1953AuJPh...6...22J    Altcode:
  No abstract at ADS