Integral field spectroscopy of extended Lyα emission from the DLA galaxy in Q2233+131

Christensen, L.; Sánchez, S. F.; Jahnke, K.;Becker, T.; Wisotzki, L.; Kelz, A.; Popović, L. Č.;Roth, M. M.. Integral field spectroscopy of extended Lyα emission from the DLA galaxy in Q2233+131. Astronomy and Astrophysics. 2004, Vol. v.417, p.487-498 , p. -2004.

This paper presents observations of an extended Lyman-α emission nebula surrounding the galaxy responsible for the Damped Lyman-α Absorption (DLA) line in the spectrum of the quasar Q2233+131. With the Potsdam Multi Aperture Spectrophotometer (PMAS) we measure the properties of the extended Lyα emission in an area of 3 arcsec × 5 arcsec having a total line flux of (2.8 ± 0.3) × 10-16 erg cm-2 s-1, which at redshift z=3.15 corresponds to a luminosity of (2.4-0.2+0.3)×1043 erg s-1 and a size of 23 × 38 kpc. The location of the emission is spatially coincident with the previously detected DLA galaxy, but extends significantly beyond its limb. We argue that the Lyα emission is likely to be caused by an outflow from the DLA galaxy, presumably powered by star formation. In the case of negligible dust extinction, the Lyα luminosity indicates a star-formation rate of 19 ± 10 Mȯ yr-1 consistent with that derived from the UV continuum flux from the parent galaxy. The wind velocity indicated by the integral field spectra is of the order of several hundred km s-1. We find no indication of emission originating in a rotating disk.