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تسجيل مستخدم جديدA uniform analysis of the Lyman alpha forest at z = 0-5: III. HST FOS Spectral Atlas
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We analyzed the absorption line spectra of all quasars observed with the high resolution gratings of the Faint Object Spectrograph on board the Hubble Space Telescope. We examined 788 spectra for 334 quasars, and present line lists and identifications of absorption lines in the spectra of 271 of them. Analysis of the statistics of the Ly-alpha and metal absorption systems are presented in companion papers (Dobrzycki et al. 2001; Scott et al. 2001; Morita et al. 2001). The data and several analysis products are available electronically and on the authors web site.
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We present results on the evolution and clustering of Ly-alpha lines at low z. The sample contains 1298 Ly-alpha lines from 165 quasar spectra mined from the archives of the HST/FOS. Our sample extends to z=1.7, slightly higher than the sample analyz
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We measure the amount of absorption in the Lyman-alpha forest at 0 < z < 1.6 in HST FOS spectra of 74 QSOs. At 0 < z < 1.6 we find that 79% of the absorption is from the low density intergalactic medium, 12% from metals and 9% from the strong H I lin
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