Assigned ID: 785 ----- Attempting Submission 1 (Fri Feb 25 23:29:49 GMT 2011) ----- The incomplete census of baryons in the low-redshift Universe is one of the outstanding problems of modern cosmology. Up to 50% of baryons are as yet unaccounted for. It is thought that the primary reservoir of missing baryons is the warm-hot intergalactic medium (or WHIM). This gas is thought to be at temperatures 5 < log T(K) < 7 mainly due to shock-heating during gravitational collapse. Metal ionization species are an ideal probe of these physical conditions. They may be seen via absorption in UV spectra of quasars. Surveys are underway to search for these metals by identifying individual absorption lines in COS spectra. We propose to measure the signal of weak, distributed absorption between these lines. In doing so, we expect to probe an equally large portion of the baryon budget as found by these surveys. We intend to achieve this by use of searches for correlated absorption that we have refined ourselves. We propose to use COS spectra that will be in the HST archive before the start of Cycle 19 and supplement this with archival STIS and FUSE spectra. We also propose to search for metal enrichment in galactic voids using the same methods and data.

COSMOLOGY 12 Medium false 0.0 0.0 false false false false SUPPORTED