Other
Scientific paper
Dec 2004
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004sf2a.conf..623p&link_type=abstract
SF2A-2004: Semaine de l'Astrophysique Francaise, meeting held in Paris, France, June 14-18, 2004. Edited by F. Combes, D. Barret
Other
Scientific paper
The column density distribution of quasar absorbers is believed to evolve over time so that different classes of quasar absorbers dominate the neutral gas content in the Universe at various redshifts. At z<3.5, damped Lyman-alpha systems (DLAs) are the major component of the HI mass. But it has been suggested that at z>3.5, 45% of the HI lies in systems below the traditional DLA definition, in ``sub-DLAs'' with 1019 < N(HI) < 2 * 1020 cm-2. A new sample of UVES spectra composed of 18 z>4 quasars is used to search for and analyse high redshift sub-DLAs. These data, together with another 22 UVES spectra from the ESO archives, allow to directly establish the column density distribution function down to N(HI) = 1019 cm-2 at various redshifts. Its evolution combined with measurements of the total amount of neutral gas are used to probe the formation epoch of damped Lyman-alpha systems.
D'Odorico Sandro
Dessauges-Zavadsky Miroslava
Kim Tae Sun
Peroux Celine
No associations
LandOfFree
Formation and evolution of quasar absorbers does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Formation and evolution of quasar absorbers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Formation and evolution of quasar absorbers will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1166529