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NOAO/KPNO - NSO, DEPARTMENT OF ASTRONOMY AND STEWARD OBSERVATORY AND NRAO

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The University of Arizona

JOINT COLLOQUIUM

DR. CHARLES C. STEIDEL

California Institute of Techology

Department of Astronomy

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will speak on the topic

"Baryonic Structure in the High Redshift Universe"

Abstract: In the past several years, there has been considerable progress made in the discovery and observation of galaxies in the high redshift universe. An interesting question is "what do we do with them?" now that they are observationally accessible and large samples are feasible. Recent results based on ensemble statistics and on detailed studies of individual objects at redshifts z~2-4 will be summarized, to provide some background on the astrophysical context of the observed galaxies. By combining faint galaxy techniques and QSO absorption line studies probing the same volumes of space, it is now possible to explore the connection between diffuse baryons in the intergalactic medium amd star forming galaxies. Example of questions that can be addressed are: What is the relative distribution of neutral hydrogen in the IGM and sites where galaxies have formed, and how does reality compare with theoretical expectations? How are metals in the IGM distributed relative to the locations of galaxies? What is the hydrodynamical effect of rapidly star forming galaxies on the local IGM? These types of observations can test fundamental ideas about the physics of the IGM and, perhaps most importantly, the influence of supernova and AGN feedback on the galaxy formation process.

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Thursday, April 10, 2003

4:00 p.m.

Steward Observatory

Lecture Hall - Room N210

Refreshments at 3:30PM in the Lobby