Friday, 6 March 2009

Evolution of Lyman alpha halos around HzRG

Zirm, Dey, Dickinson, Norman
ApJ 2009, 694, L31

Summary: The authors take STIS spectra of 5 z=1 HzRGs. 4 show extended Lyman alpha emission. The Lyman alpha halos that surround these z=1 HzRGs are smaller, and less luminous than those that surround z>2 HzRGs. The authors claim this is due to evolution of these massive galaxies. The z=1 halos are not ionized by shock heating of the infalling gas (as in the high-z halos), but rather by the AGN and star formation.

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