The thermal history of the intergalactic medium
نویسندگان
چکیده
منابع مشابه
The thermal history of the intergalactic medium
At redshifts z2, most of the baryons reside in the smooth intergalactic medium which is responsible for the low column density Lyα forest. This photoheated gas follows a tight temperature-density relation which introduces a cut-off in the distribution of widths of the Lyα absorption lines (b-parameters) as a function of column density. We have measured this cut-off in a sample of nine high reso...
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We present a new constraint on the amount of dust in the intergalactic medium (IGM) at high redshift. We derive the thermal history of the IGM by taking account of the photoelectric heating by dust grains, and compare it with the thermal history suggested by observations of Lyman α forests. As a result, if the IGM grain size is & 100 Å, the dust-gas mass ratio of the IGM at z & 2 is . 1/100 Gal...
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We have identified a large-scale structure traced by galaxies at z=0.8, within the Lockman Hole, by means of multi-object spectroscopic observations. By using deep XMM images we have investigated the soft X-ray emission from the Warm-Hot Intergalactic Medium (WHIM) expected to be associated with this large-scale structure and we set a tight upper limit to its flux in the very soft 0.2–0.4 keV b...
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Amount of intergalactic dust: constraints from distant supernovae and thermal history of intergalactic medium
This paper examines the allowed amount of IG (intergalactic) dust, which is constrained by extinction and reddening of distant SNe and thermal history of IGM (intergalactic medium) affected by dust photoelectric heating. Based on the observational cosmic star formation history, we find an upper bound of χ, the mass ratio of the IG dust to the total metal in the Universe, as χ . 0.1 for 10Å . a ...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2000
ISSN: 0035-8711,1365-2966
DOI: 10.1046/j.1365-8711.2000.03815.x