NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Baryonic Content in the Warm-Hot IGM at Low RedshiftBaryons are 4.5% of the universe's mass/energy density; only 10% of these are in stars, galaxies, and clusters. At low-redshift 90% of baryons are in the IGM, 30% in Ly-alpha forest, but most are in hot gas (10(exp 5-7) K) produced by shocks during structure formation. O VI 1032-38 A are the best tracers of this gas. The distribution of O VI absorbers observed by FUSE rises as N(sup -2+/-0.2, down to 10(exp 13)/sq cm. Integrated to logN=13, 7% of baryons reside in the O VI-bearing IGM at 10% solar metallicity, T approx. 10(exp 5.5) K. At redshift z<0.1 metals have been transported less than 800/h kpc from L* galaxies and 200/h kpc from 0.1 L* galaxies. The steepness of dN/dz means that low-N absorbers contribute an equal mass of hot IGM as higher N gas. The total mass of O VI-bearing gas in the IGM depends on determining the turnover in dN/dz at low N(O VI). Future observations by FUSE are needed to reach lower N and to reduce the uncertainty in the dN/dz power law.
Document ID
20080039154
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
Sonneborn, George
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Shull, M.
(Colorado Univ. CO, United States)
Danforth, C.
(Colorado Univ. CO, United States)
Moos, W.
(Johns Hopkins Univ. MD, United States)
Date Acquired
August 24, 2013
Publication Date
August 23, 2007
Subject Category
Astrophysics
Meeting Information
Meeting: A Century of Cosmology: Past, Present, and Future
Location: Venice
Country: Italy
Start Date: August 23, 2007
End Date: September 4, 2007
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available