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Description
We present here a dataset of quasars observed with the Ultraviolet Visual Echelle Spectrograph (UVES) on the Very Large Telescope and available in the European Southern Observatory UVES Advanced Data Products (EUADP) archive. The sample is made up of a total of 250 high resolution quasar spectra with emission redshifts ranging from 0.191<=zem<=6.311. The total UVES exposure time of this dataset is 1560 h. Thanks to the high resolution of UVES spectra, it is possible to unambiguously measure the column density of absorbers with damping wings, down to N_HI_>~10^19^cm^-2^, which constitutes the sub-damped Ly{alpha} absorber (sub-DLA) threshold. Within the wavelength coverage of our UVES data, we find 150 damped Ly{alpha} systems (DLAs)/sub-DLAs in the range 1.5<zabs<4.7. Damped absorbers, seen in the spectra of background quasars, are unique probes to select HI-rich galaxies. These galaxies allow one to estimate the neutral gas mass over cosmological scales. The neutral gas mass is a possible indicator of gas consumption as star formation proceeds. The damped Ly{alpha} absorbers (DLAs; N_HI_>=2x10^20^cm^-2^) and sub-DLAs (10^19^<=N_HI_<=2x10^20^cm^-2^) are believed to contain a large fraction of neutral gas mass in the Universe. In aper I of the series, we presented the results of a search for DLAs and sub-DLAs in the European Southern Observatory (ESO) Ultraviolet Visual Echelle Spectrograph (UVES) advanced data products dataset of 250 quasars. Here we use an unbiased subsample of sub-DLAs from this dataset to derive their statistical properties. We built a subset of 122 quasars ranging from 1.5<z_em_<5.0, suitable for statistical analysis. The statistical sample was analyzed in conjunction with other sub-DLA samples from the literature. This resulted in a combined sample of 89 sub-DLAs over a redshift path of {Delta}z=193.
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