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Study of Flare-Associated X-Ray Plasma Ejections : II. Morphological Classification

KIM, YEON-HAN; MOON, Y. -J.; CHO, K. -S. +2 more

X-Ray Emission from the Warm-Hot Intergalactic Medium

Kaastra, Jelle S.

High Dispersion Optical Spectroscopy of Planetary Nebulae

Hyung, Siek

Observational Tests of Chromospheric Magnetic Reconnection

Moon, Yong-Jae; Chae, Jongchul; Park, So-Young

Sunshine, Earthshine and Climate Change I. Origin of, and Limits on Solar Variability

Dziembowski, W. A.; Goode, Philip R.

Chandra X-Ray Observations of Early Type Galaxies

KIM, DONG-WOO

Distances of Globular Clusters based on Hipparcos Parallaxes of Nearby Subdwarfs

Lee, Sang-Gak; Saad, Somaya Mohamed

In the present study we have determined the distance moduli for seven globular clusters M2, M3, M10, M12, NGC 2808, NGC 6229 and NGC 6752, whose metallicities are in the range -1.54 < [Fe/H] < -1.10. We have derived distances for them by the main-sequence fitting method using a sample of local subdwarfs, whose accurate parallaxes are taken f…

IUE Spectra of the Seyfert 1 Galaxies Mrk 335 and NGC 4051

Hyung, Siek; Kim, Hyouk; Lee, Woo Baik +3 more

The international ultraviolet explorer (IUE) spectra of a low dispersion ~6 A, have been investigated for two Seyfert 1 galaxies, Mrk 335 and NGC 4051, well known for the line variability. The electron densities of broad line region (BLR) of these variable Seyfert 1 galaxies have been derived, which showed a non-linear abrupt variation from 1e+8 t…

Nonpotential Broadening of UV Lines Observed at the Limb of the Quiet Sun

Chae, Jongchul; Yun, Hong Sik; Lee, Hyunsook

We have done a spectroscopic study of the solar transition region using high resolution UV & EUV data obtained by SUMER) on board SOHO. Optically thin and conspicuous emission lines observed at the solar limb are carefully selected to acquire average values of physical parameters for the quiet region as a function of radial distance. Our main …

Steady Flow Model of a Magnetic Flux Tube Constrained to Observed Differential Emission Measure

Chae, Jongchul; Bong, Su-Chan; Yun, Hong Sik

We have investigated one dimensional steady flow model of a typical magnetic flux tube in the solar transition region constrained to observed Differential Emission Measure (DEM) for the average quiet-Sun deduced by Raymond & Doyle (1981) with a flux tube geometry conforming to Doppler shifts of UV lines measured by Chae, Yun & Poland (1998…