%0 Generic %1 wiseman2016evolution %A Wiseman, P. %A Schady, P. %A Bolmer, J. %A Krühler, T. %A Yates, R. M. %A Greiner, J. %A Fynbo, J. P. U. %D 2016 %K dla dust grb metal %T The evolution of the dust-to-metals ratio in high-redshift galaxies probed by GRB-DLAs %U http://arxiv.org/abs/1607.00288 %X Context: Several issues regarding the nature of dust at high redshift remain unresolved: its composition, its production and growth mechanisms, and its effect on background sources. Aims: This paper aims to provide a more accurate relation between dust depletion levels and dust-to-metals ratio (DTM), and to use the DTM to investigate the origin and evolution of dust in the high redshift Universe via GRB-DLAs. Methods: We use absorption-line measured metal column densities for a total of 19 GRB-DLAs, including five new GRB afterglow spectra from VLT/X-shooter. We use the latest linear models to calculate the dust depletion strength factor in each DLA. Using this we calculate total dust and metal column densities to determine a DTM. We explore the evolution of DTM with metallicity, and compare this to previous trends in DTM measured with different methods. Results: We find significant dust depletion in 16 of our 19 GRB-DLAs, yet 18 of the 19 have a DTM significantly lower than the Milky Way. We find that DTM is positively correlated with metallicity, which supports a dominant ISM-grain-growth mode of dust formation. We find a substantial discrepancy between the dust content measured from depletion and that derived from the total $V$-band extinction, $A_V$, measured by fitting the afterglow SED. We advise against using a measurement from one method to estimate that from the other, until the discrepancy can be resolved.

@misc{wiseman2016evolution, abstract = {Context: Several issues regarding the nature of dust at high redshift remain unresolved: its composition, its production and growth mechanisms, and its effect on background sources. Aims: This paper aims to provide a more accurate relation between dust depletion levels and dust-to-metals ratio (DTM), and to use the DTM to investigate the origin and evolution of dust in the high redshift Universe via GRB-DLAs. Methods: We use absorption-line measured metal column densities for a total of 19 GRB-DLAs, including five new GRB afterglow spectra from VLT/X-shooter. We use the latest linear models to calculate the dust depletion strength factor in each DLA. Using this we calculate total dust and metal column densities to determine a DTM. We explore the evolution of DTM with metallicity, and compare this to previous trends in DTM measured with different methods. Results: We find significant dust depletion in 16 of our 19 GRB-DLAs, yet 18 of the 19 have a DTM significantly lower than the Milky Way. We find that DTM is positively correlated with metallicity, which supports a dominant ISM-grain-growth mode of dust formation. We find a substantial discrepancy between the dust content measured from depletion and that derived from the total $V$-band extinction, $A_V$, measured by fitting the afterglow SED. We advise against using a measurement from one method to estimate that from the other, until the discrepancy can be resolved.}, added-at = {2016-07-06T10:08:04.000+0200}, author = {Wiseman, P. and Schady, P. and Bolmer, J. and Krühler, T. and Yates, R. M. and Greiner, J. and Fynbo, J. P. U.}, biburl = {https://www.bibsonomy.org/bibtex/2075586b8e77a48de2257f69c1def7227/miki}, description = {[1607.00288] The evolution of the dust-to-metals ratio in high-redshift galaxies probed by GRB-DLAs}, interhash = {f16594763200d8b94065619bd508be29}, intrahash = {075586b8e77a48de2257f69c1def7227}, keywords = {dla dust grb metal}, note = {cite arxiv:1607.00288Comment: Submitted to Astronomy & Astrophysics. 12 pages, 8 figures}, timestamp = {2016-07-06T10:08:04.000+0200}, title = {The evolution of the dust-to-metals ratio in high-redshift galaxies probed by GRB-DLAs}, url = {http://arxiv.org/abs/1607.00288}, year = 2016 }