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arXiv · 0704.0654

An integral field spectroscopic survey for high redshift damped Lyman-alpha galaxies

L. Christensen·L. Wisotzki·M. M. Roth·S. F. Sanchez·A. Kelz·K. Jahnke
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Abstract

We search for galaxy counterparts to damped Lyman-alpha absorbers (DLAs) at z>2 towards nine quasars, which have 14 DLAs and 8 sub-DLAs in their spectra. We use integral field spectroscopy to search for Ly-alpha emission line objects at the redshifts of the absorption systems. Besides recovering two previously confirmed objects, we find six statistically significant candidate Ly-alpha emission line objects. The candidates are identified as having wavelengths close to the DLA line where the background quasar emission is absorbed. In comparison with the six currently known Ly-alpha emitting DLA galaxies the candidates have similar line fluxes and line widths, while velocity offsets between the emission lines and systemic DLA redshifts are larger. The impact parameters are larger than 10 kpc, and lower column density systems are found at larger impact parameters. Assuming that a single gas cloud extends from the QSO line of sight to the location of the candidate emission line, we find that the average candidate DLA galaxy is surrounded by neutral gas with an exponential scale length of ~5 kpc.

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L. Christensen, L. Wisotzki, M. M. Roth, S. F. Sanchez, A. Kelz, K. Jahnke. 2007-04-04. An integral field spectroscopic survey for high redshift damped Lyman-alpha galaxies. https://doi.org/10.1051/0004-6361%3A20066410

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