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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…