The spin-resolved atomic velocity distribution and 21-cm line profile of dark-age gas
نویسندگان
چکیده
منابع مشابه
The spin-resolved atomic velocity distribution and 21-cm line profile of dark-age gas
The 21-cm hyperfine line of atomic hydrogen (H i) is a promising probe of the cosmic dark ages. In past treatments of 21-cm radiation it was assumed the hyperfine level populations of H i could be characterized by a velocity-independent “spin temperature” Ts determined by a competition between 21-cm radiative transitions, spin-changing collisions, and (at lower redshifts) Lyα scattering. Howeve...
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We have carried out semianalytic simulations to build redshifted 21-cm maps in the dark ages. An entropy-floor model is adopted for planting protogalaxies in simulated minihaloes. The model allocates gas quantities such as baryonic mass and temperature to every N -body particle and extensively exploits the particle nature of the data in the subsequent analysis. We have found that the number den...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2007
ISSN: 0035-8711,1365-2966
DOI: 10.1111/j.1365-2966.2006.11321.x