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We report the discovery of a super-damped Lyman-alpha absorber at $z_{abs}=2.2068$ toward QSO Q1135-0010 in the Sloan Digital Sky Survey, and follow-up VLT UVES spectroscopy. Voigt profile fit to the DLA line indicates log $N_{rm H I} = 22.05 pm 0.1$. This is the second QSO DLA discovered to date with such high $N_{rm H I}$. We derive element abundances [Si/H] = $-1.10 pm 0.10$, [Zn/H] = $-1.06 pm 0.10$, [Cr/H] = $-1.55 pm 0.10$, [Ni/H] = $-1.60 pm 0.10$, [Fe/H] = $-1.76 pm 0.10$, [Ti/H] = $-1.69 pm 0.11$, [P/H] = $-0.93 pm 0.23$, and [Cu/H] = $-0.75 pm 0.14$. Our data indicate detection of Ly-$alpha$ emission in the DLA trough, implying a star formation rate of $sim$10 $M_{odot}$ yr$^{-1}$ in the absence of dust attenuation. C II$^{*} , lambda 1336$ absorption is also detected, suggesting SFR surface density $-2 < {rm log} , dot{psi_{*}} < 0$ $M_{odot}$ yr$^{-1}$ kpc$^{-2}$. We estimate electron density in the range $3.5 times 10^{-4}$ to 24.7 cm$^{-3}$ from C II$^{*}$/C II, and $sim$0.5-0.9 cm$^{-3}$ from Si II$^{*}$/Si II. Overall, this is a robustly star-forming, moderately enriched absorber, but with relatively low dust depletion. Fitting of the SDSS spectrum yields low reddening for Milky Way, LMC, or SMC extinction curves. No CO absorption is detected, and C I absorption is weak. The low dust and molecular content, reminiscent of some SMC sight-lines, may result from the lower metallicity, and a stronger radiation field (due to higher SFR). Finally, we compare this absorber with other QSO and GRB DLAs.
We report a detection of the 9.7 micrometer silicate absorption feature in a damped Lyman-alpha (DLA) system at z_{abs} = 0.524 toward AO0235+164, using the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope. The feature shows a broad sh
We present deep ground based imaging of the environments of five QSOs that contain sub-Damped Lyman-alpha systems at z<1 with the SOAR telescope and SOI camera. We detect a clear surplus of galaxies in these small fields, supporting the assumption th
Measuring rest-frame ultraviolet rotational transitions from the Lyman and Werner bands in absorption against a bright background continuum is one of the few ways to directly measure molecular hydrogen (H2). Here we report the detection of Lyman-Wern
The amplitude of fluctuations in the Ly-a forest on small spatial scales is sensitive to the temperature of the IGM and its spatial fluctuations. The temperature of the IGM and its spatial variations contain important information about hydrogen and h