%0 Generic %1 poudel2017early %A Poudel, Suraj %A Kulkarni, Varsha P. %A Morrison, Sean %A Péroux, Céline %A Som, Debopam %A Rahmani, Hadi %A Quiret, Samuel %D 2017 %K DLA high-z metallicity %R 10.1093/mnras/stx2607 %T Early metal enrichment of gas-rich galaxies at z~5 %U http://arxiv.org/abs/1710.03315 %X We present abundance measurements of elements O, C, Si and Fe for three gas-rich galaxies at z~5 using observations from the Very Large Telescope (VLT) and the Keck telescope in order to better constrain the early chemical enrichment of gas-rich galaxies. These galaxies show strong Lyman-\alpha absorption in the spectra of background quasars, with neutral hydrogen column densities log N$_H_I$(cm$^-2$)=20.10$\pm$0.15, 20.10$\pm$0.15, and 20.80$\pm$0.15. Using the undepleted element O, we find the metallicities O/H to be in the range of -2.51 to -2.05 dex. Our study has doubled the existing sample of measurements of undepleted elements at z>4.5. Combining our measurements with those from the literature, we find that the N$_H_I$-weighted mean metallicity of z~5 absorbers is consistent with the prediction based on z<4.5 DLAs. Thus, we find no significant evidence of a sudden drop in metallicity at z>4.7 as reported by some prior studies. We also determine the extent of dust depletion using a combination of both the volatile element O and the refractory elements Si and/or Fe. Some of the absorbers show evidence of depletion of elements on dust grains, e.g. low Si/O or Fe/O. The relative abundances of these absorbers along with other z~5 absorbers from the literature show some peculiarities, e.g. low C/O in several absorbers and high Si/O in one absorber. Finally, we find that the metallicity vs. velocity dispersion relation of z~5 absorbers may be different from that of lower-redshift absorbers.

@misc{poudel2017early, abstract = {We present abundance measurements of elements O, C, Si and Fe for three gas-rich galaxies at z~5 using observations from the Very Large Telescope (VLT) and the Keck telescope in order to better constrain the early chemical enrichment of gas-rich galaxies. These galaxies show strong Lyman-{\alpha} absorption in the spectra of background quasars, with neutral hydrogen column densities log N${_H{}_I}$(cm$^{-2}$)=20.10$\pm$0.15, 20.10$\pm$0.15, and 20.80$\pm$0.15. Using the undepleted element O, we find the metallicities [O/H] to be in the range of -2.51 to -2.05 dex. Our study has doubled the existing sample of measurements of undepleted elements at z>4.5. Combining our measurements with those from the literature, we find that the N${_H{}_I}$-weighted mean metallicity of z~5 absorbers is consistent with the prediction based on z<4.5 DLAs. Thus, we find no significant evidence of a sudden drop in metallicity at z>4.7 as reported by some prior studies. We also determine the extent of dust depletion using a combination of both the volatile element O and the refractory elements Si and/or Fe. Some of the absorbers show evidence of depletion of elements on dust grains, e.g. low [Si/O] or [Fe/O]. The relative abundances of these absorbers along with other z~5 absorbers from the literature show some peculiarities, e.g. low [C/O] in several absorbers and high [Si/O] in one absorber. Finally, we find that the metallicity vs. velocity dispersion relation of z~5 absorbers may be different from that of lower-redshift absorbers.}, added-at = {2017-10-11T10:09:37.000+0200}, author = {Poudel, Suraj and Kulkarni, Varsha P. and Morrison, Sean and Péroux, Céline and Som, Debopam and Rahmani, Hadi and Quiret, Samuel}, biburl = {https://www.bibsonomy.org/bibtex/24f0ec6015c1e24e53455da86680c20a0/miki}, description = {[1710.03315] Early metal enrichment of gas-rich galaxies at z~5}, doi = {10.1093/mnras/stx2607}, interhash = {405ec767e67ecf59d52dcb0bf8298854}, intrahash = {4f0ec6015c1e24e53455da86680c20a0}, keywords = {DLA high-z metallicity}, note = {cite arxiv:1710.03315Comment: 15 pages, 14 figures, accepted for publication in MNRAS}, timestamp = {2017-10-11T10:09:37.000+0200}, title = {Early metal enrichment of gas-rich galaxies at z~5}, url = {http://arxiv.org/abs/1710.03315}, year = 2017 }