Extended Lyman Alpha Emission Around Young Quasars: A Constraint on Galaxy Formation

Preprint
Publisher Website
Google Scholar
  • 11 January 2001
Abstract
The early stage in the formation of a galaxy inevitably involves a spatially extended distribution of infalling, cold gas. If a central luminous quasar turned on during this phase, it would result in significant extended Lyman alpha emission (possibly accompanied by other lines), detectable as a ``fuzz'' of characteristic angular diameter of a few arcseconds, and surface brightness exceeding 10^-18 erg/s/cm^2/asec^2. From the apparent paucity of such Lyman alpha halos, we infer that most of the protogalaxy's gas must settle to a self-gravitating disk before a quasar turns on, or else that an intense outflow from the quasar quickly blows out the surrounding gas. Continued infall of gas from large radii, or an on-going merger spreading cold gas over a large solid angle, during the luminous quasar phase could also result in significant extended Lyman alpha emission, and can be constrained by deep narrow band imaging.

This publication has 0 references indexed in Scilit: