Evidence for Cold Accretion onto a Massive Galaxy at High Redshift?
نویسندگان
چکیده
In this letter we report on the discovery of a z=2.83 Lyman-α Blob (LAB) found in our wide field narrow-band survey within the Spitzer First Look Survey region. The blob is extended over at least 95kpc and has a total Lyman-α luminosity of 2.1×10 erg s. It is only the sixth LAB known of this scale (> 50 kpc), and is associated with an embedded continuum source in g’, R, i’, K & 4.5 μm bands. The LAB’s optical spectrum shows clumpy structures and tantalising hints of a sharp red cut-off and shear within the Ly-α emission line. Studies of the LAB’s surface brightness profile and of the continuum counterpart’s spectral energy distribution (SED) indicate that the profuse Lyman-α emission is consistent with being powered by cold gas accreting onto a massive dark matter halo.
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