Open AccessHeating of the intergalactic medium as a result of structure formation
Author(s) -
Nath Biman B.,
Silk Joseph
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2001.04832.x
Subject(s) - physics , astrophysics , redshift , equation of state , intergalactic medium , structure formation , intergalactic travel , shock (circulatory) , baryon , shock wave , distortion (music) , galaxy , thermodynamics , medicine , amplifier , optoelectronics , cmos
We estimate the heating of the intergalactic medium as a result of shocks arising from structure formation. The heating of the gas outside the collapsed regions, with small overdensities is considered here, with the aid of a Zel'dovich approximation. We estimate the equation of state of this gas, relating the density to its temperature and its evolution in time, considering the shock heating caused by 1 σ density peaks as being the most dominant. We also estimate the mass fraction of gas above a given temperature as a function of redshift. We find that the baryon fraction above 10 6 K at is ∼ 10 per cent. We estimate the integrated Sunyaev–Zel'dovich distortion from this gas at present epoch to be of the order of 10 −6 .