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Evidence for Cold Accretion onto a Massive Galaxy at High Redshift?

Daniel J. B. Smith·Matt J. Jarvis
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Abstract

In this letter we report on the discovery of a z=2.83 Lyman-alpha 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-alpha luminosity of 2.1 x 10^44 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 um bands. The LAB's optical spectrum shows clumpy structures and tantalising hints of a sharp red cut-off and shear within the Ly-alpha 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-alpha emission is consistent with being powered by cold gas accreting onto a massive dark matter halo.

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Daniel J. B. Smith, Matt J. Jarvis. 2007-04-30. Evidence for Cold Accretion onto a Massive Galaxy at High Redshift?. https://doi.org/10.1111/j.1745-3933.2007.00318.x

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