The ESO UVES advanced data products quasar sample

Abstract

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 archive. The sample is made up of a total of 250 high resolution quasar spectra with emission redshifts ranging from 0.191 ≤ z em ≤ 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 H I 10 19 cm −2 , which constitutes the sub-damped Lyα absorber (sub-DLA) threshold. Within the wavelength coverage of our UVES data, we find 150 damped Lyα systems (DLAs)/sub-DLAs in the range 1.5 < z abs < 4.7. Of these 150, 93 are DLAs and 57 are sub-DLAs. An extensive search in the literature indicates that 6 of these DLAs and 13 of these sub-DLAs have their N H I measured for the first time. Among them, 10 are new identifications as DLAs/sub-DLAs. For each of these systems, we obtain an accurate measurement of the H i column density and the absorber's redshift in the range 1.7 < z abs < 4.2 by implementing a Voigt profile-fitting algorithm. These absorbers are further confirmed thanks to the detection of associated metal lines and/or lines from members of the Lyman series. In our data, a few quasars' lines-of-sight are rich. An interesting example is towards QSO J0133+0400 (z em = 4.154) with six DLAs and sub-DLAs reported.

The ESO UVES advanced data products quasar sample – III. Evidence of bimodality in the [N/α] distribution

“…Zafar et al (2013b) have taken advantages of the ESO advanced data archive to build the so-called EU-ADP (ESO UVES Advanced Data Products) sample of highresolution quasar spectra. The data were post-processed and analysed to look for the DLAs and sub-DLAs they contain.…”

The ESO UVES Advanced Data Products Quasar Sample – IV. On the deficiency of argon in DLA systems

“…Details on building and processing of the EUADP sample are presented in Zafar et al (2013b). This EUADP sample of 250 quasar spectra has been used to study DLAs/sub-DLAs (Zafar et al 2013a).…”

A Unique View of AGN-driven Molecular Outflows: The Discovery of a Massive Galaxy Counterpart to a Z = 2.4 High-metallicity Damped Lyα Absorber

“…Kashikawa et al 2014;Zafar et al 2017). Compared with either the statistical sample of DLAs from the Sloan Digital Sky Survey, which contains over 12,000 z > 2 DLAs (Noterdaeme et al 2012a), or the several hundred DLAs with high-resolutions spectroscopy (see, e.g., Zafar et al 2013;Jorgenson et al 2013), the sample of galaxy counterparts is remarkably small. Given the current small sample, additional discoveries are critical both to our understanding of the nature of DLAs and sub-DLAs, as well as to our understanding of galaxy formation.…”