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Author name code: makita
ADS astronomy entries on 2022-09-14
author:"Makita, Mitsugu"
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Title: Demonstration of an x-ray Raman spectroscopy setup to study
warm dense carbon at the high energy density instrument of European
XFEL
Authors: Voigt, K.; Zhang, M.; Ramakrishna, K.; Amouretti, A.; Appel,
K.; Brambrink, E.; Cerantola, V.; Chekrygina, D.; Döppner, T.;
Falcone, R. W.; Falk, K.; Fletcher, L. B.; Gericke, D. O.; Göde,
S.; Harmand, M.; Hartley, N. J.; Hau-Riege, S. P.; Huang, L. G.;
Humphries, O. S.; Lokamani, M.; Makita, M.; Pelka, A.; Prescher, C.;
Schuster, A. K.; Šmíd, M.; Toncian, T.; Vorberger, J.; Zastrau,
U.; Preston, T. R.; Kraus, D.
2021PhPl...28h2701V Altcode:
We present a proof-of-principle study demonstrating x-ray Raman
Spectroscopy (XRS) from carbon samples at ambient conditions in
conjunction with other common diagnostics to study warm dense
matter, performed at the high energy density scientific instrument
of the European x-ray Free Electron Laser (European XFEL). We obtain
sufficient spectral resolution to identify the local structure and
chemical bonding of diamond and graphite samples, using highly annealed
pyrolytic graphite spectrometers. Due to the high crystal reflectivity
and XFEL brightness, we obtain signal strengths that will enable
accurate XRS measurements in upcoming pump-probe experiments with a
high repetition-rate, where the samples will be pumped with high-power
lasers. Molecular dynamics simulations based on density functional
theory together with XRS simulations demonstrate the potential of this
technique and show predictions for high-energy-density conditions. Our
setup allows simultaneous implementation of several different diagnostic
methods to reduce ambiguities in the analysis of the experimental
results, which, for warm dense matter, often relies on simplifying
model assumptions. The promising capabilities demonstrated here provide
unprecedented insights into chemical and structural dynamics in warm
dense matter states of light elements, including conditions similar
to the interiors of planets, low-mass stars, and other celestial bodies.
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Title: Laboratory measurements of resistivity in warm dense plasmas
relevant to the microphysics of brown dwarfs
Authors: Booth, N.; Robinson, A. P. L.; Hakel, P.; Clarke, R. J.;
Dance, R. J.; Doria, D.; Gizzi, L. A.; Gregori, G.; Koester, P.;
Labate, L.; Levato, T.; Li, B.; Makita, M.; Mancini, R. C.; Pasley, J.;
Rajeev, P. P.; Riley, D.; Wagenaars, E.; Waugh, J. N.; Woolsey, N. C.
2015NatCo...6.8742B Altcode: 2015NatCo...6E8742B
Since the observation of the first brown dwarf in 1995, numerous
studies have led to a better understanding of the structures
of these objects. Here we present a method for studying material
resistivity in warm dense plasmas in the laboratory, which we relate
to the microphysics of brown dwarfs through viscosity and electron
collisions. Here we use X-ray polarimetry to determine the resistivity
of a sulphur-doped plastic target heated to Brown Dwarf conditions by
an ultra-intense laser. The resistivity is determined by matching the
plasma physics model to the atomic physics calculations of the measured
large, positive, polarization. The inferred resistivity is larger than
predicted using standard resistivity models, suggesting that these
commonly used models will not adequately describe the resistivity of
warm dense plasma related to the viscosity of brown dwarfs.
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Title: The energy spectrum of the light components (P+He) at the
knee obtained by the Tibet air shower core detector
Authors: Katayose, Y.; Amenomori, M.; Ayabe, S.; Chen, D.; Cui, S. W.;
Danzengluobu; Ding, L. K.; Ding, X. H.; Feng, C. F.; Feng, Z. Y.;
Gao, X. Y.; Geng, Q. X.; Guo, H. W.; He, H. H.; He, M.; Hibino, K.;
Hotta, N.; Haibing, Hu; Hu, H. B.; Huang, J.; Huang, Q.; Jia, H. Y.;
Kajino, F.; Kasahara, K.; Kato, C.; Kawata, K.; Labaciren; Le, G. M.;
Li, J. Y.; Lu, H.; Lu, S. L.; Meng, X. R.; Mizutani, K.; Mu, J.;
Munakata, K.; Nagai, A.; Nanjo, H.; Nishizawa, M.; Ohnishi, M.; Ohta,
I.; Onuma, H.; Ouchi, T.; Ozawa, S.; Ren, J. R.; Saito, T.; Sakata,
M.; Sasaki, T.; Shibata, M.; Shiomi, A.; Shirai, T.; Sugimoto, H.;
Makita, M.; Tan, Y. H.; Tateyama, N.; Torii, S.; Tsuchiya, H.; Udo,
S.; Wang, H.; Wang, X.; Wang, Y. G.; Wu, H. R.; Xue, L.; Yamamoto,
Y.; Yan, C. T.; Yang, X. C.; Yasue, S.; Ye, Z. H.; Yu, G. C.; Yuan,
A. F.; Yuda, T.; Zhang, H. M.; Zhang, J. L.; Zhang, N. J.; Zhang,
X. Y.; Zhang, Y.; Zhang, Yi; Zhaxisangzhu; Zhou, X. X.
2005ICRC....6..185A Altcode: 2005ICRC...29f.185A
No abstract at ADS
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Title: Calibration of the instrumental polarization of the Domeless
Solar Telescope at the Hida Observatory
Authors: Kiyohara, Junko; Ueno, Satoru; Kitai, Reizaburo; Kurokawa,
Hiroki; Makita, Mitsugu; Ichimoto, Kiyoshi
2004SPIE.5492.1778K Altcode:
A new spectropolarimeter is developed at the Domeless Solar Telescope
(DST) in Hida Observatory. It consists of a rotating waveplate,
Wollaston prisms, and a high-dispersion spectrograph which is
vertically installed at the focus of the DST. In order to realize
a high-precision measurement, it is inevitable to compensate the
instrumental polarization due to the DST. We observed the quiet
region of the Sun, which is considered to be highly unpolarized,
with and without a sheet linear polarizer or circular polarizer
set at the entrance window of the telescope. The theoretical model
which represents the total instrumental polarization of the DST with
some characteristic parameters was calculated and compared with the
observation. The model that two flat mirrors have different properties
can explain the observation in 0.5% accuracy for the unpolarized light,
and in 7% for the polarized light.
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Title: On the nature of the suspected dwarf nova, HP Andromedae
Authors: Nogami, D.; Ishioka, R.; Makita, M.; Kato, T.; Yamaoka, H.;
Uemura, M.; Mineshige, S.
2003IBVS.5416....1N Altcode:
The object having been identified with HP And is not a dwarf nova.
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Title: Chromospheric structure derived from flash spectra of the
total solar eclipse
Authors: Makita, Mitsugu
2003PNAOJ...7....1M Altcode:
A chromosphere model for the analysis of emission lines in a flash
spectrum is constructed. Emission gradients of metallic and Balmer lines
in flash spectra give height distributions of the total hydrogen and
the product of electron and proton density in the high chromosphere,
respectively. The derived distributions imply the presence of "spicule"
structure which has a filling factor of 0.05 at 4,000 km above the base
of the chromosphere. They explain the averaged eclipse curves of Ca II H
and K, and Hɛ line profiles observed in a 1958 flash spectrum and the
Balmer and Sr II emissions observed in a 1962 flash spectrum. Their
excitation and ionization seem to match the radiation field of the
chromosphere. They are applied to 24 Ca II H and K spicules in the
higher chromosphere observed during the 1958 eclipse. The analysis
shows that they have a turbulence of 22 km/s on the average and 19 of
them are thinner than 2,000 km. The Ca II H and K, and Hɛ emissions
of the active region observed during the 1958 eclipse are enhanced
mainly by the increase of their source functions due to an increase
in their excitation temperatures.
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Title: Emission line eclipse mapping of velocity fields in dwarf
nova accretion discs
Authors: Makita, M.; Mineshige, S.
2002ASPC..261..501M Altcode: 2002pcvr.conf..501M
We propose a new method, emission-line eclipse mapping, to map the
velocity fields in an accretion disc. We apply the usual eclipse
mapping technique to the light curves at each of 12-24 wavelengths
across the line center to map the region with same line-of-sight
velocity, from which we are able to plot the rotational velocity
as a function of radius on the assumption of axisymmetric disc. We
calculate time changes of the emission line profiles, assuming Keplerian
rotation fields (v<SUB>varphi</SUB> propto r<SUP>-1/2</SUP>) and the
emissivity distribution of j propto r<SUP>-3/2</SUP>, and reconstruct
emissivity profiles. The results show typically a `two-eye' pattern
for high line-of-sight velocities and we can recover the relation,
v<SUB>varphi</SUB> propto d<SUP>-1/2</SUP>, where d is the separation
of two lq eyes.'
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Title: Numerical Simulation of Interaction between an L1 Stream and
an Accretion Disk in a Close Binary System
Authors: Fujiwara, H.; Makita, M.; Nagae, T.; Takuya
2001PThPh.106..729F Altcode: 2001astro.ph..9238F
Numerical simulation of the hydrodynamic behavior of an accretion disk
in a close binary system is reported. Calculations were carried out for
a region including a compact star and its gas-supplying companion. The
equation of state is that of an ideal gas characterized by a specific
heat ratio γ. Two cases, with γ=1.01 and γ=1.2, are studied. Our
calculations show that the gas, flowing from the companion via a
Lagrangian L1 point towards the accretion disk, forms a fine gas beam
(L1 stream), which penetrates into the disk. Thus, no hot spot forms in
these calculations. Another result is that the gas rotating with the
disk forms ---upon collision with the L1 stream--- a bow shock wave,
which we call an `L1 shock'. The disk becomes hot because the L1 shock
heats the disk gas in the outer parts of the disk, so that the spiral
shocks wind loosely, even with γ=1.01. The L1 shock enhances axial
asymmetry of the density distribution in the disk, and therefore angular
momentum is transferred through the tidal torque more effectively. The
maximum value of the effective α becomes ~ 0.3. A `hot spot' is not
formed in our simulations, but our results suggest the formation of
a `hot line', which is the L1 shock elongated along the penetrating
L1 stream.
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Title: WZ Sagittae.
Authors: Baba, H.; Sadakane, K.; Norimoto, Y.; Nogami, D.; Matsumoto,
K.; Makita, M.; Kato, T.
2001IAUC.7678....2B Altcode:
No abstract at ADS
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Title: WZ Sagittae
Authors: Kato, T.; Ohashi, H.; Ishioka, R.; Uemura, M.; Matsumoto,
K.; Masi, G.; Starkey, D.; Pietz, J.; Martin, B.; Baba, H.; Sadakane,
K.; Norimoto, Y.; Nogami, D.; Makita, M.
2001IAUC.7678....1K Altcode: 2001IAUC.7678A...1K
T. Kato, H. Ohashi, R. Ishioka, M. Uemura and K. Matsumoto, Kyoto
University; G. Masi, Ceccano, Italy; D. Starkey, Auburn, Indiana;
J. Pietz, Erftstadt, Germany; and B. Martin, The King's University
College, Edmonton, Alberta, on behalf of the VSNET collaboration team,
report: "Our time-resolved CCD photometry revealed that WZ Sge started
to show a different type of prominent modulations (amplitude 0.10 mag)
on Aug. 4.53 UT. Between Aug. 4.44 and 5.08 the oscillations had an
initial period of 0.057143 +/- 0.000046 day, which is 0.8 percent
longer than the orbital period (0.05669 day). Earlier observations,
starting on Aug. 4.163, also showed a suggestion of the growing
signal. Later observations, between Aug. 5.166 and 6.074, have shown
further development of superhumps up to 0.23 mag and give a mean period
of 0.058876 +/- 0.000025 day. The sharply defined profile and the
period excess qualify the present variations as genuine superhumps. The
superhumps developed from the secondary hump structure of the early
superhumps (IAUC 7672). The 12-day delay of superhump evolution since
the start of the outburst is the longest one measured among all known
SU UMa-type dwarf novae. The observed delay is consistent with the
earliest time of detection of a similar, but less distinct, signal
during the 1978 outburst (Heiser and Henry, IBVS 1559)." H. Baba,
National Astronomical Observatory of Japan; K. Sadakane, Osaka-Kyoiku
University; Y. Norimoto, Okayama Astrophysical Observatory (OAO);
and D. Nogami, K. Matsumoto, M. Makita and T. Kato, Kyoto University,
report: "We constructed Doppler tomograms of WZ Sge using time-resolved
spectra (resolution about 3000) covering two binary orbits between July
24.576 and 24.701 UT with the OAO 0.91-m telescope (IAUC 7672). The He
II (468.6 nm) map shows that the emitting region on the accretion disk
is elongated along the ballistic stream, which constitutes an asymmetric
'boomerang-like' one-armed spiral structure. The present observation
shows the earliest detection of presence of the spiral structure of the
emission line. Since Steeghs et al. (IAUC 7675) reported that the He II
and C III emission lines were dominated by a two-armed spiral pattern
four days after the maximum, there must have been a dramatic change in
the emission pattern between our earlier observation and theirs. Such
a totally unprecedented, unexpected change may be responsible for the
growth of early superhumps."
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Title: Spiral Shocks in an Inviscid Simulation of Accretion Flow in
a Close Binary System
Authors: Makita, M.; Fujiwara, H.; Matsuda, T.; Boffin, H. M. J.
2001LNP...573...88M Altcode: 2001astr.conf...88M
We perform 2D and 3D numerical simulations of an accretion disc in
a close binary with a mass ratio of 0.5, corresponding to the dwarf
nova IP Pegasi. We do not include artificial nor α-viscosity and
supply gas from the inner L1 point. We construct Doppler maps and
artificial trailed spectrograms. In the 2D calculation, the results
agree very well with those observed in IP Peg. In the 3D calculations,
the stream from the L1 point penetrates into the accretion disc. The
resulting flow pattern, therefore, is different from the 2D results.
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Title: Eclipse Curves of Ca H, K, and Hɛ Structures
Authors: Makita, M.
2000ASPC..205...97M Altcode: 2000ltse.conf...97M
Eclipse curves of Ca H, K, and Hɛ structures are obtained from the
1958 flash spectrum. Under the active region, Ca and Hɛ lines are
enhanced by 0.2 and 0.3 in logarithmic scale, respectively. Ca line
ratio K/H is greater than 1 and seems not to reach 2. 58% of Ca line
profiles below 2500 km do not show central dips but single peaks. Width
difference of Ca and Hɛ lines may give kinetic temperature of 9000circ
K for isolated structures.
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Title: 3D numerical simulation of accretion disc
Authors: Matsuda, T.; Fujiwara, H.; Makita, M.; Nagae, T.; Oka, K.;
Boffin, H.
2000NewAR..44P..21M Altcode:
No abstract at ADS
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Title: Spiral Structure in IP Peg: Confronting Theory and
Observations<SUP>CD</SUP>
Authors: Matsuda, T.; Makita, M.; Yukawa, H.; Boffin, H. M. J.
1999ASSL..240..207M Altcode: 1998astro.ph..7239M; 1999numa.conf..207M
The first convincing piece of evidence of spiral structure in the
accretion disc in IP Pegasi was found by Steeghs et al. (1997). We
performed two kinds of 2D hydrodynamic simulations, a SFS finite volume
scheme and a SPH scheme, with a mass ratio of 0.5. Both results agreed
well with each other. We constructed Doppler maps and line flux-binary
phase relations based on density distributions, the results agreeing
well with those obtained by observation.
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Title: 3D Simulations of the Spiral Structure
Authors: Matsuda, T.; Makita, M.; Boffin, H. M. J.
1999dicb.conf..129M Altcode:
No abstract at ADS
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Title: 3D Finite Volume Simulation of Accretion Discs with Spiral
Shocks<SUP>CD</SUP>
Authors: Makita, M.; Matsuda, T.
1999ASSL..240..227M Altcode: 1999numa.conf..227M; 1998astro.ph..7237M
We perform 2D and 3D numerical simulations of an accretion disc in a
close binary system using the Simplified Flux vector Splitting (SFS)
finite volume method. In our calculations, gas is assumed to be the
ideal one, and we calculate the cases with gamma=1.01, 1.05, 1.1 and
1.2. The mass ratio of the mass losing star to the mass accreting
star is unity. Our results show that spiral shocks are formed on
the accretion disc in all cases. In 2D calculations we find that the
smaller gamma is, the more tightly the spiral winds. We observe this
trend in 3D calculations as well in somewhat weaker sense.
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Title: Spiral Shocks in Accretion Discs: Comparing models with
observations
Authors: Makita, M.; Yukawa, H.; Matsuda, T.; Boffin, H. M. J.
1999dicb.conf..147M Altcode:
No abstract at ADS
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Title: The Proper Motion of Individual Sunspots
Authors: Herdiwijaya, Dhani; Makita, Mitsugu; Anwar, Bachtiar
1997PASJ...49..235H Altcode:
The proper motions of 276 individual sunspots were observed with
a triple-exposures method, and then analyzed. Their linear drifts
give the mean motions (degree day(-1) ), which, depending on the
heliographic latitude B, are the differential rotation, omega (B) =
14.5 - 2.5sin (2B) , and the equatorward meridional flow, v_B =-0.05sin
2B. The deviations of the linear drift from the mean motions have a
small correlation between the longitudinal and latitudinal ones, which
correspond to the equatorial acceleration. The deviations in longitude
are clearly separated by the sunspot polarities. The average separation
velocity between the preceding and following polarities is 52 m s(-1)
. The drifts of individual sunspots corrected for the mean motion are
the smallest for the Zurich GHJ class. However, they are fairly large
and may influence the determination of the mean motion. Short-term
variations appear as positional deviations from the linear-drift
curve. These fast drifts are detected in the active Zurich classes,
and are one order of magnitude larger than the linear drift.
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Title: Distributions of the Magnetic Field Inclination in Sunspots
Authors: Shinkawa, T.; Makita, M.
1996mpsa.conf..615S Altcode: 1996IAUCo.153..615S
No abstract at ADS
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Title: Rapid Sunspot Motion during a Major Solar Flare
Authors: Anwar, B.; Acton, L. W.; Hudson, H. S.; Makita, M.; McClymont,
A. N.; Tsuneta, S.
1993SoPh..147..287A Altcode:
A major solar flare on 15 November, 1991 produced a striking
perturbation in the position and shape of the sunspot related most
closely to the flare. We have studied these perturbations by use of the
aspect-sensor images from the Soft X-ray Telescope on board YOHKOH,
and with ground-based data from the Mees Solar Observatory. The
perturbation occurred during the impulsive phase of the flare, with
a total displacement on the order of 1 arc sec. The apparent velocity
of approximately 2 km s<SUP>−1</SUP> exceeds that typically reported
for sunspot proper motions even in flare events. We estimate that the
magnetic energy involved in displacing the sunspot amounted to less
than 4 × 10<SUP>30</SUP> ergs, comparable to the radiant energy from
the perturbed region. Examination of the Mees Observatory data shows
that the spot continued moving at lower speed for a half-hour after
the impulsive phase. The spot perturbation appears to have been a
result of the coronal restructuring and flare energy release, rather
than its cause.
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Title: Magnetograph Observations of Solar Faculae
Authors: Kawakami, Singo; Makita, Mitsugu
1993PASJ...45..255K Altcode:
Two solar facular regions were investigated using the Solar Vector
Magnetograph of the Okayama Astrophysical Observatory. The transverse
magnetic field of the faculae becomes more parallel to the solar radius
as the facular region moves from the disk center to the limb. This
center-to-limb variation can be explained by a numerical simulation in
which the direction of facular magnetic fields is confined within a
cone around the vertical. A suitable cone angle is about 30(deg) . This
confinement leads to the possibility of calibrating a magnetograph
measurement by considering the center-to-limb variation of the
longitudinal and transverse magnetic fields.
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Title: Effective Lande factors of the solar spectral lines in 5000
Å - 7000 Å and sunspot magnetic fields.
Authors: Makita, M.; Yatagai, H.; Nakamura, K.; Fujikawa, T.;
Hirose, S.
1993MmKyo..38..255M Altcode:
The effective Lande factors of the solar spectral lines in the
wavelength region 5000 - 7000 Å are tabulated. As an application of
this table, sunspot spectra are analyzed to statistically determine
the magnetic field strength.
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Title: Ten Years of the Okayama Vector Magnetograph
Authors: Makita, M.; Sakurai, T.; Shibasaki, K.; Koyano, H.
1993ASPC...46..180M Altcode: 1993IAUCo.141..180M; 1993mvfs.conf..180M
No abstract at ADS
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Title: Polarization of the Domeless Solar Telescope of the Hida
Observatory (Preliminary report).
Authors: Makita, M.; Funakoshi, Y.; Hanaoka, Y.
1991sopo.work..198M Altcode:
Instrumental polarization of the Domeless Solar Telescope (DST)
are measured with an accuracy of 1 per cent. The variation of the
Stokes parameters from sunrise to sunset is reproduced by adopting
probable optical constants for the two oblique reflection mirrors
in the telescope. The entrance and exit vacuum windows affect the
polarization less than the measured accuracy.
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Title: Active regions, sunspots and their magnetic fields.
Authors: Semel, Meir; Mouradian, Zadig; Soru-Escaut, Irina; Maltby,
Per; Rees, David; Makita, Mitsugu; Sakurai, Takashi
1991sia..book..844S Altcode:
Surface magnetism is the progenitor of active regions, sunspots, and
all related phenomena. This cause and effect is reversible so that,
using well-established empirical laws, the presence and morphology of
photospheric magnetic fields can be deduced from active-region light
emission structure. In the (simplifying) case of sunspots, MHD and
thermodynamic theory find some success in the interpretation of the
interaction of magnetic fields and solar plasma. Coronal magnetic fields
also appear to be predictable by extrapolation techniques starting
from the photospheric conditions. Alternatively, surface magnetism can
be observed "directly" by means of the spectroscopic Zeeman effect
and Stokes polarimetry. Eventually these empirical, theoretical and
direct-measurement techniques must converge to identical results as
we better understand the physics of active regions.
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Title: Detailed comparison of transverse magnetic fields of the sun
with H-alpha fine structures
Authors: Kawakami, Singo; Makita, Mitsugu; Kurokawa, Hiroki
1989PASJ...41..175K Altcode:
Vectormagnetograms obtained at the Okayama Astrophysical Observatory
are compared in detail with H-alpha filtergrams taken with the Domeless
Solar Telescope at Hida Observatory for three active regions. The
coincidence rate between the azimuth of transverse magnetic fields and
elongated H-alpha dark fine structures decreases as the active region
moves on the solar disk from the center to the limb. This center-to-limb
variation of the azimuthal coincidence rate can be explained by the
difference of elevation angle between the photospheric and chromospheric
magnetic fields. The analysis of three active regions shows that,
in a more active region, the magnetic field is more inclined in the
photosphere, and more sheared in the vertical direction. Three active
regions show different values of the azimuthal coincidence rate, and
these differences are discussed in connection with the magnetic field
configuration and the evolutional characteristics of the individual
active regions.
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Title: On the structure of the sunspot magnetic field deduced from
broadband circular polarization
Authors: Makita, Mitsugu
1988VA.....31...63M Altcode:
The characteristics of the broad-band circular polarization of sunspots
are confirmed for sunspots of the new solar cycle. It is stronger on the
limb-side of sunspots and its polarity is always positive (negative)
for S (N) magnetic polarity in three recent solar cycles. The sunspot
model of an unwinding emerging magnetic field proposed in the previous
analysis is illustrated.
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Title: An experiment on the relation between incident and emerging
light beams of optical fibers.
Authors: Makita, M.; Imai, H.
1988TokRe..21..129M Altcode:
No abstract at ADS
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Title: Measurement of the magnetic vector on the sun at the Okayama
Astrophysical Observatory.
Authors: Makita, Mitsugu; Hamana, Shigeo; Sakurai, Takashi; Shimizu,
Minoru
1987LIACo..27..185M Altcode: 1987oahp.proc..185M
Observations taken in Japan beginning in 1982 have been used to
obtain magnetic vectors on the sun. Investigation of drift curves
of the measured polarization shows that the residual instrumental
polarization can be represented by trigonometric functions of twice
the sun's hour angle. Peak-to-peak amplitudes of fluctuations in the
line wing (5250 A) and in the neighboring continuum (5282-5297 A) are
0.0041 and 0.0001 respectively. The observed radial velocity drifts
linearly at the rate of about 0.2 to 1 km/s/hr. It is suggested that
corrections could give the accuracy of 10 m/s.
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Title: An Interpretation of the Broad Band Circular Polarization
of Sunspots
Authors: Makita, Mitsugu
1986SoPh..106..269M Altcode:
The broad-band circular polarization of sunspots is discussed on
the basis of the observations made in the Okayama Astrophysical
Observatory. The observation with the spectrograph proves that it
is the integrated polarization of spectral lines in the observed
spectral range. A velocity gradient in the line-of-sight can produce
this integrated polarization due to the differential saturation between
Zeeman components of magnetically sensitive lines. The observed degree
of polarization and its spatial distribution in sunspots is explained
when we introduce a differentially twisted magnetic field in addition to
the velocity gradient. The differential twist has the azimuth rotation
of the magnetic field along the line-of-sight and generates the circular
polarization from the linear polarization due to the magneto-optical
effect. The required azimuth rotation is reasonable and amounts at
most to 30°. The required velocity gradient is compatible with the
line asymmetry and its spatial distribution observed in sunspots. The
observed polarity rule leads to the conclusion that the sunspot magnetic
field has the differential twist with the right-handed azimuth rotation
relative to the direction of the main magnetic field, without regard
to the magnetic polarity and to the solar cycle. The twist itself is
left-handed under the photosphere, when the sunspot is assumed to be
a unwinding emerging magnetic field.
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Title: A Detection of the Faraday Rotation by the Solar Vector
Magnetograph
Authors: Makita, M.
1986SoPh..103....1M Altcode:
The Faraday rotation in the sunspot atmosphere is statistically detected
by examining directions of the linear polarization obtained with the
vector magnetograph of the Okayama Astrophysical Observatory. It is very
effective near the spectral line center and the azimuth of the linear
polarization deviates greatly from the magnetic field azimuth. In the
case of the iron line, 5250 Å, the magnetic field azimuth will be
obtained with an accuracy better than 15°, if observed in the line
wing from 27 to 80 mÅ relative to the line center.
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Title: The broad-band polarization of sunspots observed from 8
February 1981to 30 August 1982.
Authors: Makita, Mitsugu; Ohki, Yoshina
1986AnTok..21....1M Altcode: 1986AOTok..21....1M
The broad-band polarization of sunspots was measured with the
polarimeter fed to the solar coudé telescope of the Okayama
Astrophysical Observatory. 113 polarization maps of 41 sunspot groups
were obtained during this period. The observed circular polarization
is strong in the limb of sunspots, roughly in proportion to the linear
polarization. Its polarity is negative or positive according as the
magnetic polarity is north or south. This polarity rule is found to
be the same as that in the previous solar cycle.
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Title: A study of line asymmetry in unipolar sunspots
Authors: Makita, M.; Kawakami, H.
1986PASJ...38..257M Altcode:
The asymmetry of the line profile of Fe I (6301.5 A) in the spectrum
of unipolar sunspots was analyzed. Most bisectors of the line profile
could be approximated by straight lines and interpreted in terms of
the variation of the line-of-sight velocity. The analysis of these
bisectors, under the assumption of cylindrical symmetry, gives a
sunspot-velocity structure consistent with that deduced from the
Evershed outflow and inflow. The azimuthal flow increases downward to
satisfy the vorticity-polarity rule proposed by the Meudon observers
(Matries et al., 1973). Among the line profiles not approximated by
the linear bisector, inverse-C shape profiles are most likely to occur
in the umbra.
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Title: Observation of Magnetic Field Vector in Solar Active Regions
Authors: Sakurai, T.; Makita, M.
1986hmps.conf...53S Altcode:
No abstract at ADS
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Title: Solar vector magnetograms of the Okayama Astrophysical
Observatory.
Authors: Makita, M.
1986saot.conf..237M Altcode:
The solar vector magnetograph of the Okayama Astrophysical Observatory
has been operated since the end of 1982. The observational data usually
obtained are briefly described.
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Title: Solar Vector Magnetograms of the Okayama Astrophysical
Observatory
Authors: Makita, Mitsugu; Hamana, Shigeo; Nishi, Keizo; Shimizu,
Minoru; Sakurai, Takashi; Shibasaki, Kiyoto
1986Ap&SS.118..163M Altcode:
The title instrument is mounted on the 65 cm solar Coudé telescope
at the Okayama observatory. Observation is usually of the Fe i 5250
Å line. The data obtained are briefly described.
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Title: Observation of Magnetic Field Vector in Solar Active Regions
Authors: Sakurai, T.; Makita, M.; Shibasaki, K.
1985tphr.conf..313S Altcode:
The vector magnetograph at Okayama Astrophysical Observatory has been
in operation since 1982. The conversion from the observed polarization
degrees to the magnetic field components is made by using Unno's formula
(1956) applied to a homogeneous magnetic field.
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Title: Comparisons of simultaneous vector magnetograms
Authors: Makita, M.; Nishi, K.; Shimizu, M.; Hamana, S.; Sakurai,
T.; Grigoryev, V. M.; Kuklin, G. V.; Selivanov, V. L.
1985svmf.nasa..399M Altcode:
Simultaneous vector magnetograms were obtained with the different
magnetographs of the Okayama Astrophysical Observatory and the Sayan
Mountain Observatory in October 1983. The data obtained show a good
correspondence in general. The comparison makes clear something on the
measuring accuracy of each magnetograph. Good correspondence is shown
in circular and linear polarizations, and, in and near sunspots, of the
velocity field. The azimuth of the magnetic fields show good agreement.
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Title: The solar vector magnetograph of the Okayama Astrophysical
Observatory
Authors: Makita, M.; Hamana, S.; Nishi, K.
1985svmf.nasa..173M Altcode:
The vector magnetograph of the Okayama Astrophysical Observatory
is fed to the 65 cm solar coude telescope with a 10 m Littrow
spectrograph. The polarimeter put at the telescope focus analyzes
the incident polarization. Photomultipliers (PMT) at the exit of the
spectrograph pick up the modulated light signals and send them to the
electronic controller. The controller analyzes frequency and phase
of the signal. The analyzer of the polarimeter is a combination of a
single wave plate rotating at 40 Hz and a Wallaston prism. Incident
linear and circular polarizations are modified at four times and twice
the rotation frequency, respectively. Two compensators minimize the
instrumental polarization, mainly caused by the two tilt mirrors in
the optical path of the telescope. The four photomultipliers placed on
the wings of the FeI 5250A line give maps of intensity, longitudinal
field and transverse field. The main outputs, maps of intensity, and
net linear and circular polarizations in the neighboring continuum
are obtained by the other two monitor PMTs.
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Title: The solar vector magnetograph of the Okayama Astrophysical
Observatory.
Authors: Makita, M.; Hamana, S.; Nishi, K.
1985NASCP2374..173M Altcode:
The vector magnetograph of the Okayama Astrophysical Observatory
is fed to the 65 cm solar coudé telescope with a 10 m Littrow
spectrograph. The polarimeter put at the telescope focus (solar image
size = 31 cm) analyzes the incident polarization. Photomultipliers (PMT)
at the exit of the spectrograph pick up the modulated light signals and
send them to the electronic controller. The controller makes frequency
and phase analyses of the signal, and the results are digitized and
stored on the magnetic disk of the mini-computer. The operation of
the complete vector magnetograph became possible in autumn 1982. Some
preliminary data mainly on solar active regions were published recently
(Sakurai and Makita, 1984).
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Title: Comparisons of simultaneous vector magnetograms.
Authors: Makita, M.; Nishi, K.; Shimizu, M.; Hamana, S.; Sakura, T.;
Grigoryev, V. M.; Grigor'ev, V. M.; Kuklin, G. V.; Selivanov, V. L.
1985NASCP2374..399M Altcode:
Simultaneous vector magnetograms were obtained with the different
magnetographs of the Okayama Astrophysical Observatory and the Sayan
Mountain Observatory in October 1983. The data obtained show a good
correspondence in general. The comparison makes clear something on
the measuring accuracy of each magnetograph.
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Title: Observations by the solar vector magnetograph of the Okayama
Astrophysical Observatory.
Authors: Makita, M.; Hamana, S.; Nishi, K.; Shimizu, M.; Koyano, H.;
Sakurai, T.; Komatsu, H.
1985PASJ...37..561M Altcode: 1985PASJ...37..561H
The vector magnetograph of the Okayama Astrophysical Observatory has
been in operation since the fall of 1982. The instrument, operation,
and data reduction are described briefly. Some observations of the
development of a small active region, a flare, and azimuths of the
magnetic field relative to the Hα fine structure are reported. The
accuracy of the measurement is limited by the incident photon number
and as good as 0.1 % in the degree of polarization.
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Title: Observation of magnetic field vector in solar active regions.
Authors: Sakurai, T.; Makita, M.; Shibasaki, K.
1985MPARp.212..312S Altcode:
The vector magnetograph at Okayama Astrophysical Observatory has been
in operation since 1982. The conversion from the observed polarization
degrees to the magnetic field components is made by using Unno's formula
(1956) applied to a homogeneous magnetic field.
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Title: A solar vector magnetograph.
Authors: Makita, M.
1983AstHe..76..284M Altcode:
No abstract at ADS
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Title: Magnetic and Velocity Fields of Emerging Flux Regions on
the Sun
Authors: Martres, M. J.; Rayrole, J.; Semel, M.; Soru-Escaut, I.;
Tanaka, K.; Makita, M.; Moriyama, F.; Unno, W.
1982PASJ...34..299M Altcode:
Emerging Flux Regions (EFR's) on the Sun observed in the Meudon-Mitaka
Collaborative Solar Observation Program (1979) are discussed. <P />The
rule found earlier (Martres et al. 1973) for the growth (or decay) of
the N polarity or the decay (or growth) of the S polarity magnetic field
in relation to the photospheric clockwise (or counterclockwise) vortex
motion is reconfirmed for the EFR in the present solar cycle. The rule
is emphasized as an indication of active generation of an electric
current system by a photospheric motion. <P />The chromospheric
manifestations of EFR's seen in Hα as arch filament systems (AFS's) and
the enhanced brightness are examined with respect to the photospheric
magnetic field structure derived from the white light and magnetic
observations. An isolated EFR is associated with an AFS which is
well coaligned with the photospheric transverse field. The typical
EFR configuration may be distorted if the EFR appears in the region
of the pre-existing strong field. The observational characteristics
of such EFR's can also be interpreted in terms of the emergence of a
nearly potential field associated with the dissipation of an excess
magnetic energy. An EFR born in an older EFR shows that the flux loop
is low-lying and tends to relax into a potential field configuration.
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Title: High accuracy measurement of the instrumental polarization of
the solar coudé telescope at the Okayama Astrophysical Observatory.
Authors: Makita, M.; Hamana, S.; Kawakami, H.; Nishi, K.
1982AnTok..19...24M Altcode: 1982AOTok..19...24M
No abstract at ADS
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Title: Wide-Band Polarization of Sunspots
Authors: Makita, M.
1980jfss.conf...99M Altcode:
No abstract at ADS
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Title: Three Component Magnetic Fields of Sunspots
Authors: Kawakami, H.; Makita, M.
1980jfss.conf..107K Altcode:
No abstract at ADS
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Title: Determination of the Magnetic Field from the Zeeman Line
Profile
Authors: Makita, M.
1979PASJ...31..575M Altcode:
A method applying the theoretical solution of the radiative transfer
problem with the magnetic field to the observed Zeeman line profile
is developed. The assumptions of a pure-absorption atmosphere and
of no magneto-optical effect allow a model-free determination of the
magnetic field averaged along the optical depth. Depth variation of
line-profile parameters, such as the Doppler shift, Doppler width,
damping constant, magnetic field strength, and tilt of the magnetic
line of force, is obtained. <P />The present method of analysis is
applied to a penumbral spectrum observed on May 10, 1971 and has shown
an inward magnetic field, whose strength is 1500 G, making an angle
of 34° against the solar surface, and an outward Evershed flow of
5.6 km s<SUP>-1</SUP>, parallel to the magnetic line of force.
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Title: The effective optical depth for the formation of absorption
lines.
Authors: Makita, M.
1977SoPh...51...43M Altcode:
The contribution function method used so far to define the effective
depth for the formation of absorption lines is discussed and a new
definition of the effective depth is proposed. The effective depth is
the level where a thin slab having the equivalent optical thickness
to the total line absorption is placed so as to give the observed
line intensity.
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Title: Magnetic field gradient in a sunspot umbra.
Authors: Makita, M.; Nemoto, K.
1976PASJ...28..495M Altcode:
Echelle spectrograms of three sunspot umbrae were obtaiaed with a
wide wavelength-range analyzer of the circular polarization at the
Okayama Astrophysical Observatory. The magnetic field derived from
the Zeeman shift of many absorption lines cannot be interpreted by
a single spectrum, but suggests a composite of two spectra, one of
which is due to a cool atmosphere with magnetic field and the other
due to a hot atmosphere without magnetic field. The hot component
can be attributed to the stray light due to the seeing or to umbral
structure, or both. The analysis, taking into account the composite
nature, leads to a magnetic field gradient of G . A reanalysis of 's
(1969) data, obtained also with the cchelle spectrograph, gives JH/dk
>-0.7 G km-1. Key words: Echelle spectrum; Magnetic field; Sunspot.
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Title: Measurements of the Magnetic Field Vector of a Sunspot
Authors: Nishi, K.; Makita, M.
1973PASJ...25...51N Altcode:
A new polarimetric observation of the Fraunhofer line 6302.5A was made
along the line profile considering the reduction of the instrumental
polarization. The existence of a nearly horizontal magnetic field in the
penumbra was confirmed. It was also found that the field direction was
along the filamentary structure of the penumbra. Key words: Magnetic
field; Polarization; Sunspots.
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Title: The Chromosphere in Continuum Emission Observed at the Total
Solar Eclipse on 7 March 1970
Authors: Makita, Mitsugu
1972SoPh...24...59M Altcode:
Direct images of the Sun were photographed in continuum emission
centered at 6900 Å by the jumping film method near the second
contact of the Mexico eclipse on 7 March 1970. The band width was
150 Å defined by a combination of a sharp cut filter and KODAK IV F
film. The intensity distribution of the solar outer layers obtained
shows a steep decrease by a factor of 0.9 in logarithmic units around
2500 km. This is interpreted as the boundary of the chromosphere and
corona. Spicules observed at 3500 km are explained by log n<SUB>e</SUB>
= 11.25 and T<SUB>e</SUB> ≈ 6000 K. Discussions are made in relation
to the other observations and some chromosphere models.
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Title: The preliminary report of the observations of the March 7,
1970 total solar eclipse in Mexico.
Authors: Saito, K.; Makita, M.; Hata, S.; Tojo, A.
1971TokRe..15..445S Altcode:
No abstract at ADS
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Title: A polarization compensator designed for the solar coudé
telescope at the Okayama Astrophysical Observatory.
Authors: Makita, M.
1970AnTok..12..139M Altcode: 1970AOTok..12..139M
No abstract at ADS
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Title: Instrumental polarization of the solar coudé telescope and
spectrograph at the Okayama Astrophysical Observatory.
Authors: Makita, M.; Nishi, K.
1970AnTok..12..121M Altcode: 1970AOTok..12..121M
No abstract at ADS
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Title: A non-spherical axisymmetric model of the solar K corona of
the minimum type
Authors: Saito, Kuniji; Makita, Mitsugu; Nishi, Keizo; Hata, Shigeru
1970AnTok..12...53S Altcode: 1970AOTok..12...53S; 1970AnTok..12...51S
No abstract at ADS
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Title: A Study of the Green TiO Band in the Sunspot Spectrum
Authors: Makita, Mitsugu
1968SoPh....3..557M Altcode:
The equivalent widths of the TiO lines in the α system have been
measured on a high dispersion (11 mm/Å) spectrogram of large
sunspot. The lines were so weak that the measurement was made by
methods giving maximum and minimum equivalent widths, depending on the
adopted continuum. The rotational temperature obtained in this way
was about 3000 °K. The result is unaffected by stray light because
there are no TiO lines in the undisturbed spectrum. The calculation
of equivalent widths using several sunspot models (all of which can
satisfy the observed data) shows that the logarithmic optical depth
at the effective layer of molecular line formation is about -1.6.
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Title: The Scattering Function Obtained from Partial Solar Eclipse
Authors: Makita, M.
1966PASJ...18..345M Altcode:
The direct image of the sun was photographed at a partial solar eclipse,
and from the moon's limb occulting the solar disk the profile of the
scattering function was obtained. The profiles thus obtained do not
fit a Gaussian. Near the core they look like a dispersion function,
but in the wing they decrease faster than this. The working hypothesis
of the preceding paper that the scattering function is the sum of two
Gaussian profiles seemes to be a goed approximation.
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Title: On the two component model of sunspot umbrae
Authors: Makita, M.
1964susp.conf..177M Altcode:
No abstract at ADS
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Title: The Effect of Atmospheric Turbulence on the Solar Image
and Sunspots
Authors: Makita, M.; Morimoto, M.
1964PASJ...16....1M Altcode:
On the basis of the photoelectric and photographic observations of
the solar limb and sunspots, the shape of the scattering function
is discussed and the pro posal is made that it is the sum of two
Gaussian functions. The result does not change the previous condusion
that the atmosphere of the sunspot umbra consists of two components,
one hot and the other cold. The photoelectric observations give some
information as to the size, frequency spectrum, and dependence of the
atmospheric turbulence and, moreover, as to the correlations between
the atmospheric turbulence and weather and between observations made
with different instruments.
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Title: Physical States in Sunspots
Authors: Makita, M.
1963PASJ...15..145M Altcode:
The physical state in sunspots were studied by the line spectra,
which were obtained photographically with the tower telescope of
the Tokyo Astronowical Observatory, combined with the temperature
distribution obtained by the photoelectric method reported in the
previous paper. Throughout the study only the ratio of photospheric
and sunspot equivalent widths was discussed, because it is independent
of the abundance of the element and gf-value and, therefore, one can
use many unblended weak lines, for which the equivalent widths can
casily be calculated on the basis of pure absorption. The procedure
was to find the temperature and electron pressure distributions in
sunspots which give best fit to the observed ratios. The model of
the penumbra obtained has the following properties; 1) It is nearly
in radiative equilibrium of the plain parallel atmosphere, 2) It is
about two times transparent than the photosphere, 3) It departs from
hydrostatic equilibrium, but this can be explained by the reasonable
magnetic field parallel to the Evershed flow, and 4) It balances the
surrounding photosphere by the Evershed flow. As far as the uniform
model is assumed, no consistent model could be found in the case of
the umbra because of the presence of too high excitation lines, which
led to very low values of pressure in deep layers and required the
unreasonable magnetic and velocity flelds in order for the mechanical
balance to attain horizontally and vertically. Mter some discussions
the two component model having the following properties was proposed;
1) The high excitation lines are chiefly formed in the hot component
of the atmosphere composed of the cold and hot components, 2) The two
components are both in hydrostatic equilibrium, 3) The hot component
occupies about one tenth of the umbra in area and emits about half
of the total radiation at 5000A, and 4) The radiation temperatures of
both components are about and .
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Title: Photoelectric Study of Sunspots
Authors: Makita, M.; Morimoto, M.
1960PASJ...12...63M Altcode:
The continuum of sunspot spectra was observed simultaneously at three
wave lengths with the tower telescope of the Tokyo Astronomical
Observatory, using the photoelectric and the rotating prism which
reduced the effect of scintillation appreciably. The intensity ratio
to area relation and the limb effect of sunspots are obtained and from
the latter the temperature distribution is derived for the penumbra
an the umbra ( and at .5 respectively). The obtained temperature
distribution of the umbra with the area=70.10-6 of solar hemisphere
is on the average lower than Michard's.
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Title: Convective Instability in Polytropic Atmospheres, I
Authors: Unno, W.; Kato, S.; Makita, M.
1960PASJ...12..192U Altcode:
The condition of the onset of thermal convection is studied for
polytropic atmospheres in which both the coefficients of viscosity
and thermal conductivity are assumed to be constant. A polytropic
variation for the disturbance is assumed for simplicity, and the
non-dimensional number, crit, characterizing the condition of marginal
stability is computed for the most unstable mode with the use of the
variational principle. Actual computations have been made for a few
polytropic atmospheres having considerable changes in density from top
to bottom. The results are compared to those of the classical Rayleigh
problem, and it turns out that the critical Rayleigh number Rcrot,
and the associated horizontal wavenumber depend very little on the
density variation in the atmosphere, provided that the transformation
from crit to Rcrot is made with the use of the density and temperature
at the average height in the atmosphere. The effect of the simplifying
assumption of polytropic variation on the above argument will be
examined in a subsequent paper in which the effect is found to be
unimportant.
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Title: Inhibition of Convection by a Magnetic Field
Authors: Makita, M.
1958PASJ...10....1M Altcode:
The stability of the stellar atmosphere in the presence of a magnetic
field is considered using the usual hydrornagnetic equations. It i
that initiallv the magnetic field is homogeneous and the atmosphere is
hydrostatic We can derive the extended Wale n's criterion neglecting
higher order disturbances than the second. The criterion is applied to
the solar convection zone and 200 gauss is obtained for the magnetic
field strength of penumbra.
