Spectroscopic Studies of the Solar Corona II. Properties of Green and Red Emission Lines in Open and Closed Coronal Structures

AbstractThe results of photometry of colour positives of the solar corona of July 11, 1991 are presented. Observations of the white corona were made without radial niters in Jojutla (Mexico). Dependences of coronal brightness on distance in the red (640 nm) and blue (420 nm) wavelength intervals are deduced for different coronal structures up to 3.0-3.5R⊙. The effect of ”reddening“ is noted. The excess of the red emission to the blue one (I640nm/I420nm) is found to be 1.20 and 1.17 at distance of 2.2R⊙for the N-E helmet streamer (P ≃ 37°) and the N-W region of low brightness (P ≃ 339°), respectively.

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Spectroscopic studies of solar corona VI: Trend in line-width variation of coronal emission lines with height independent of the structure of coronal loops

Journal of Astrophysics and Astronomy ◽

10.1007/bf02702514 ◽

2006 ◽

Vol 27 (2-3) ◽

pp. 115-124 ◽

Cited By ~ 3

Author(s):

Jagdev Singh ◽

Takashi Sakurai ◽

Kiyoshi Ichimoto ◽

S. Muneer

Keyword(s):

Solar Corona ◽

Line Width ◽

Spectroscopic Studies ◽

Emission Lines ◽

Coronal Loops ◽

Coronal Emission

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Spectroscopic Studies of Solar Corona VIII. Temperature and Non-Thermal Variations in Steady Coronal Structures

Solar Physics ◽

10.1007/s11207-006-0104-7 ◽

2006 ◽

Vol 236 (2) ◽

pp. 245-262 ◽

Cited By ~ 8

Author(s):

Jagdev Singh ◽

Takashi Sakurai ◽

Kiyoshi Ichimoto ◽

S. Muneer ◽

A. V. Raveendran

Keyword(s):

Solar Corona ◽

Spectroscopic Studies ◽

Coronal Structures

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Calculated Coronal Magnetic Fields and Their Comparison with the Coronal Structures as Observed during Five Solar Eclipses

International Astronomical Union Colloquium ◽

10.1017/s0252921100026038 ◽

1994 ◽

Vol 144 ◽

pp. 559-564

Author(s):

P. Ambrož ◽

J. Sýkora

Keyword(s):

Magnetic Field ◽

Solar Cycle ◽

Magnetic Fields ◽

Solar Corona ◽

Coronal Magnetic Field ◽

Coronal Magnetic Fields ◽

Solar Eclipses ◽

Coronal Structures

AbstractWe were successful in observing the solar corona during five solar eclipses (1973-1991). For the eclipse days the coronal magnetic field was calculated by extrapolation from the photosphere. Comparison of the observed and calculated coronal structures is carried out and some peculiarities of this comparison, related to the different phases of the solar cycle, are presented.

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Exploring Coronal Structures with SOHO

International Astronomical Union Colloquium ◽

10.1017/s0252921100064915 ◽

2000 ◽

Vol 179 ◽

pp. 403-406

Author(s):

M. Karovska ◽

B. Wood ◽

J. Chen ◽

J. Cook ◽

R. Howard

Keyword(s):

Solar Corona ◽

Image Enhancement ◽

Coronal Mass Ejections ◽

Dynamical Evolution ◽

Small Scale ◽

Low Contrast ◽

Contrast Structures ◽

Scale Structures ◽

Small Scale Structures ◽

Coronal Structures

AbstractWe applied advanced image enhancement techniques to explore in detail the characteristics of the small-scale structures and/or the low contrast structures in several Coronal Mass Ejections (CMEs) observed by SOHO. We highlight here the results from our studies of the morphology and dynamical evolution of CME structures in the solar corona using two instruments on board SOHO: LASCO and EIT.

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Spectroscopic Studies of the Solar Corona I. Spatial Variations in Line Parameters of Green and Red Coronal Lines

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/51.2.269 ◽

1999 ◽

Vol 51 (2) ◽

pp. 269-276 ◽

Cited By ~ 19

Author(s):

J. Singh ◽

K. Ichimoto ◽

H. Imai ◽

T. Sakurai ◽

A. Takeda

Keyword(s):

Solar Corona ◽

Spectroscopic Studies ◽

Spatial Variations

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Spectroscopic studies of Wolf-Rayet stars. IV - Optical spectrophotometry of the emission lines in galactic and large Magellanic Cloud stars

The Astrophysical Journal ◽

10.1086/167101 ◽

1989 ◽

Vol 337 ◽

pp. 251 ◽

Cited By ~ 93

Author(s):

Peter S. Conti ◽

Philip Massey

Keyword(s):

Large Magellanic Cloud ◽

Spectroscopic Studies ◽

Magellanic Cloud ◽

Emission Lines ◽

Optical Spectrophotometry

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A Discussion on the physics of the solar atmosphere - Spectroscopic studies of the solar corona at x-ray wavelengths

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1976.0036 ◽

1976 ◽

Vol 281 (1304) ◽

pp. 383-390 ◽

Cited By ~ 10

Keyword(s):

Spatial Distribution ◽

Solar Corona ◽

Spatial Variation ◽

Resonance Line ◽

Active Regions ◽

Resonance Scattering ◽

Spectroscopic Studies ◽

Line Of Sight ◽

X Ray ◽

Forbidden Transitions

The spatial distribution of the emission in several X-ray lines is discussed with emphasis on temperature dependence and association with active regions. New results are presented for the trio of helium-like O vii lines which demonstrate (1) a spatial variation in the density dependent forbidden to intersystem line ratio, and (2) a strong spatial variation in the intensity of the O vii resonance line relative to the optically forbidden transitions. The second effect appears to be caused by resonance scattering by material in the line of sight.

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