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- W2106630557 abstract "<i>Aims. <i/>We aim to understand the nature of the absorbing neutral gas in the galaxies hosting high-redshift long-duration gamma-ray bursts (GRBs) and to determine their physical conditions.<i>Methods. <i/>A detailed analysis of high-quality VLT/UVES spectra of the optical afterglow of GRB 050730 and other <i>Swift<i/>-era bursts is presented.<i>Results. <i/>We report the detection of a significant number of previously unidentified allowed transition lines of Fe<sup>+<sup/>, involving the fine structure of the ground term ( <sup>6<sup/>D<sub>7/2<sub/>, <sup>6<sup/>D<sub>5/2<sub/>, <sup>6<sup/>D<sub>3/2<sub/>, <sup>6<sup/>D<sub>1/2<sub/>) and that of other excited levels (<sup>4<sup/>F<sub>9/2<sub/>, <sup>4<sup/>F<sub>7/2<sub/>, <sup>4<sup/>F<sub>5/2<sub/>, <sup>4<sup/>F<sub>3/2<sub/>, <sup>4<sup/>D<sub>7/2<sub/>, <sup>4<sup/>D<sub>5/2<sub/>), from the = 3.969, log <i>N<i/>(H<sup>0<sup/>) = 22.10, damped Lyman-<i>α<i/> (DLA) system located in the host galaxy of GRB 050730. No molecular hydrogen (H<sub>2<sub/>) is detected down to a molecular fraction of log <i>f<i/> < -8.0. We derive accurate metal abundances for Fe<sup>+<sup/>, S<sup>+<sup/>, N<sup>0<sup/>, Ni<sup>+<sup/>, and, for the first time in this system, Si<sup>+<sup/> and Ar<sup>0<sup/>. The absorption lines are best-fit as a single narrow velocity component at = 3.96857. The time-dependent evolution of the observed Fe<sup>+<sup/> energy-level populations is modelled by assuming the excitation mechanism is fluorescence following excitation by ultraviolet photons emitted by the afterglow of GRB 050730. This UV pumping model successfully reproduces the observations, yielding a total Fe<sup>+<sup/> column density of log <i>N<i/> = 15.49<i>±<i/>0.03, a burst/cloud distance (defined to the near-side of the cloud) of <i>d<i/> = 440<i>±<i/>30 pc, and a linear cloud size of <i>l<i/> = pc. This application of our photo-excitation code demonstrates that burst/DLA distances can be determined without strong constraints on absorption-line variability provided enough energy levels are detected. From the cloud size, we infer a particle density of <i>n<i/><sub>H<sub/> <i>≈<i/> 5-15 cm<sup>-3<sup/>.<i>Conclusions. <i/>We discuss these results in the context of no detections of H<sub>2<sub/> and C i lines (with log <i>N<i/>(C<sup>0<sup/>)/<i>N<i/>(S<sup>+<sup/>) < -3) in a sample of seven GRB host galaxies observed with VLT/UVES. We show that the lack of H<sub>2<sub/> can be explained by the low metallicities, [X/H] < -1, low depletion factors, and, at most, moderate particle densities of the systems. This points to a picture where GRB-DLAs typically exhibiting very high H<sup>0<sup/> column densities are diffuse metal-poor atomic clouds with high kinetic temperatures, 1000 K, and large physical extents, <i>l<i/> 100 pc. The properties of GRB-DLAs observed at high spectral resolution towards bright GRB afterglows differ markedly from the high metal and dust contents of GRB-DLAs observed at lower resolution. This difference likely results from the effect of a bias, against systems of high metallicity and/or close to the GRB, due to dust obscuration in the magnitude-limited GRB afterglow samples observed with high-resolution spectrographs." @default.
- W2106630557 created "2016-06-24" @default.
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- W2106630557 date "2009-08-27" @default.
- W2106630557 modified "2023-10-16" @default.
- W2106630557 title "Physical conditions in high-redshift GRB-DLA absorbers observed with VLT/UVES: implications for molecular hydrogen searches" @default.
- W2106630557 cites W1494728497 @default.
- W2106630557 cites W1505734076 @default.
- W2106630557 cites W1532014147 @default.
- W2106630557 cites W174732049 @default.
- W2106630557 cites W1760802502 @default.
- W2106630557 cites W1913860194 @default.
- W2106630557 cites W1964005981 @default.
- W2106630557 cites W1972336358 @default.
- W2106630557 cites W1983763252 @default.
- W2106630557 cites W1984082866 @default.
- W2106630557 cites W1987560521 @default.
- W2106630557 cites W1995778743 @default.
- W2106630557 cites W2003271886 @default.
- W2106630557 cites W2004052728 @default.
- W2106630557 cites W2015679879 @default.
- W2106630557 cites W2021983948 @default.
- W2106630557 cites W2024922695 @default.
- W2106630557 cites W202492466 @default.
- W2106630557 cites W2028940079 @default.
- W2106630557 cites W2034316564 @default.
- W2106630557 cites W2035879704 @default.
- W2106630557 cites W2039874334 @default.
- W2106630557 cites W2040615387 @default.
- W2106630557 cites W2042857033 @default.
- W2106630557 cites W2051989818 @default.
- W2106630557 cites W2052403425 @default.
- W2106630557 cites W2054872331 @default.
- W2106630557 cites W2055865075 @default.
- W2106630557 cites W2064888972 @default.
- W2106630557 cites W2072433121 @default.
- W2106630557 cites W2077431059 @default.
- W2106630557 cites W2079085438 @default.
- W2106630557 cites W2079320824 @default.
- W2106630557 cites W2080029870 @default.
- W2106630557 cites W2084775107 @default.
- W2106630557 cites W2086199187 @default.
- W2106630557 cites W2088926159 @default.
- W2106630557 cites W2091747578 @default.
- W2106630557 cites W2096471541 @default.
- W2106630557 cites W2102188495 @default.
- W2106630557 cites W2103734507 @default.
- W2106630557 cites W2105698732 @default.
- W2106630557 cites W2110899101 @default.
- W2106630557 cites W2110906056 @default.
- W2106630557 cites W2111817932 @default.
- W2106630557 cites W2114317630 @default.
- W2106630557 cites W2114800671 @default.
- W2106630557 cites W2125396253 @default.
- W2106630557 cites W2127888706 @default.
- W2106630557 cites W2134857842 @default.
- W2106630557 cites W2136054245 @default.
- W2106630557 cites W2139971953 @default.
- W2106630557 cites W2148069702 @default.
- W2106630557 cites W2157706105 @default.
- W2106630557 cites W2159264410 @default.
- W2106630557 cites W2160325921 @default.
- W2106630557 cites W2164134530 @default.
- W2106630557 cites W2314847211 @default.
- W2106630557 cites W2949308084 @default.
- W2106630557 cites W3098025488 @default.
- W2106630557 cites W3098576613 @default.
- W2106630557 cites W3098820749 @default.
- W2106630557 cites W3099137176 @default.
- W2106630557 cites W3099575410 @default.
- W2106630557 cites W3099586693 @default.
- W2106630557 cites W3099953098 @default.
- W2106630557 cites W3100112514 @default.
- W2106630557 cites W3100685835 @default.
- W2106630557 cites W3101917313 @default.
- W2106630557 cites W3102298780 @default.
- W2106630557 cites W3102582642 @default.
- W2106630557 cites W3103843170 @default.
- W2106630557 cites W3104766469 @default.
- W2106630557 cites W3105221715 @default.
- W2106630557 cites W3105472298 @default.
- W2106630557 cites W3122051790 @default.
- W2106630557 cites W3124412437 @default.
- W2106630557 cites W4211105962 @default.
- W2106630557 cites W4290042687 @default.
- W2106630557 doi "https://doi.org/10.1051/0004-6361/200811572" @default.
- W2106630557 hasPublicationYear "2009" @default.
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