Continuum Emission by Cooling Clouds
نویسنده
چکیده
The collapse of baryons into the center of a host dark matter halo is accompanied by radiation that may be detectable as compact ( < ∼ 10 kpc) UV-continuum and Lyα emission with Lyα luminosities as high as ∼ 1042 −1043 erg s−1 in halos of mass M = 1011 − 10M⊙. We show that the observed equivalent width (EW) of the Lyα line emitted by these cooling clouds is EW < ∼ 400 Å (restframe). These luminosities and EWs are comparable to those detected in narrowband surveys for redshifted Lyα emission. The rest-frame ultraviolet of Lyα emitting cooling clouds radiation may be dominated by two-photon transitions from 2s→1s. The resulting spectrum can distinguish cooling clouds from a broad class of young star forming galaxies. Subject headings: cosmology: theory–galaxies: high redshift–galaxies: formation–radiation mechanisms: general
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Continuum Emission Associated with Cooling Clouds
The collapse of baryons into the center of a host dark matter halo is accompanied by emission of cooling radiation, possibly in regions extending up to ∼ 100 kpc. This cooling radiation may have been detected already as spatially extended Lyman α ’blobs’ at z = 3−5. However, Lyα cooling radiation may also be detectable as compact ( < ∼ 10 kpc) emission with luminosities as high as ∼ 10 − 10 erg...
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