A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements
Ultraviolet absorption line spectroscopy is a sensitive diagnostic for the properties of interstellar and circumgalactic gas. Down-the-barrel observations, where the absorption is measured against the galaxy itself, are commonly used to study feedback from galactic outflows and to make predictions a...
Saved in:
| Main Authors: | , , , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/ad9b13 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1841525577379479552 |
|---|---|
| author | R. Michael Jennings Alaina Henry Valentin Mauerhofer Timothy Heckman Claudia Scarlata Cody Carr Xinfeng Xu Mason Huberty Simon Gazagnes Anne E. Jaskot Jeremy Blaizot Anne Verhamme Sophia R. Flury Alberto Saldana-Lopez Matthew J. Hayes Maxime Trebitsch |
| author_facet | R. Michael Jennings Alaina Henry Valentin Mauerhofer Timothy Heckman Claudia Scarlata Cody Carr Xinfeng Xu Mason Huberty Simon Gazagnes Anne E. Jaskot Jeremy Blaizot Anne Verhamme Sophia R. Flury Alberto Saldana-Lopez Matthew J. Hayes Maxime Trebitsch |
| author_sort | R. Michael Jennings |
| collection | DOAJ |
| description | Ultraviolet absorption line spectroscopy is a sensitive diagnostic for the properties of interstellar and circumgalactic gas. Down-the-barrel observations, where the absorption is measured against the galaxy itself, are commonly used to study feedback from galactic outflows and to make predictions about the leakage of H i ionizing photons into the intergalactic medium. Nonetheless, the interpretation of these observations is challenging, and observational compromises are often made in terms of signal-to-noise ratio, spectral resolution, or the use of stacking analyses. In this paper, we present a novel quantitative assessment of UV absorption line measurement techniques by using mock observations of a hydrodynamical simulation. We use a simulated galaxy to create 22,500 spectra in the commonly used Si ii lines while also modeling the signal-to-noise ratio and spectral resolution of recent rest-frame UV galaxy surveys at both high and low redshifts. We show that the residual flux of absorption features is easily overestimated for single line measurements and for stacked spectra. Additionally, we explore the robustness of the partial covering model for estimating column densities from spectra and find underpredictions on an average of 1.25 dex. We show that the underprediction is likely caused by high-column-density sight lines that are optically thick to dust making them invisible in UV spectra. |
| format | Article |
| id | doaj-art-d677413f020e43ab81522be955d02eaa |
| institution | Kabale University |
| issn | 1538-4357 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj-art-d677413f020e43ab81522be955d02eaa2025-01-17T08:48:49ZengIOP PublishingThe Astrophysical Journal1538-43572025-01-0197916410.3847/1538-4357/ad9b13A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line MeasurementsR. Michael Jennings0https://orcid.org/0000-0002-3959-6572Alaina Henry1https://orcid.org/0000-0002-6586-4446Valentin Mauerhofer2https://orcid.org/0000-0003-0595-9483Timothy Heckman3https://orcid.org/0000-0001-6670-6370Claudia Scarlata4https://orcid.org/0000-0002-9136-8876Cody Carr5https://orcid.org/0000-0003-4166-2855Xinfeng Xu6https://orcid.org/0000-0002-9217-7051Mason Huberty7https://orcid.org/0009-0002-9932-4461Simon Gazagnes8https://orcid.org/0000-0002-5659-4974Anne E. Jaskot9https://orcid.org/0000-0002-6790-5125Jeremy Blaizot10https://orcid.org/0000-0003-1609-7911Anne Verhamme11https://orcid.org/0000-0002-2201-1865Sophia R. Flury12https://orcid.org/0000-0002-0159-2613Alberto Saldana-Lopez13https://orcid.org/0000-0001-8419-3062Matthew J. Hayes14https://orcid.org/0000-0001-8587-218XMaxime Trebitsch15https://orcid.org/0000-0002-6849-5375Center for Astrophysical Sciences, Department of Physics & Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA ; rjenni11@jhu.eduCenter for Astrophysical Sciences, Department of Physics & Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA ; rjenni11@jhu.edu; Space Telescope Science Institute ; 3700 San Martin Drive, Baltimore, MD 21218, USAKapteyn Astronomical Institute, University of Groningen , P.O Box 800, 9700 AV Groningen, The NetherlandsCenter for Astrophysical Sciences, Department of Physics & Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA ; rjenni11@jhu.eduMinnesota Institute for Astrophysics, University of Minnesota , 116 Church Street SE, Minneapolis, MN 55455, USACenter for Cosmology and Computational Astrophysics, Institute for Advanced Study in Physics, Zhejiang University , Hangzhou 310058, People's Republic of China; Institue of Astronomy, School of Physics, Zhejiang University , Hangzhou 310058, People's Republic of ChinaDepartment of Physics and Astronomy, Northwestern University , 2145 Sheridan Road, Evanston, IL 60208, USA; Center for Interdisciplinary Exploration and Research inAstrophysics (CIERA), Northwestern University , 1800 Sherman Avenue, Evanston, IL 60201, USAMinnesota Institute for Astrophysics, University of Minnesota , Minneapolis, MN 55455, USADepartment of Astronomy, The University of Texas at Austin , 2515 Speedway, Stop C1400, Austin, TX 78712-1205, USADepartment of Astronomy, Williams College , Williamstown, MA 01267, USAUniv Lyon , Univ Lyon1, ENS de Lyon, CNRS, Centre de Recherche Astrophysique de Lyon UMR5574, F-69230 Saint-Genis-Laval, FranceUniv Lyon , Univ Lyon1, ENS de Lyon, CNRS, Centre de Recherche Astrophysique de Lyon UMR5574, F-69230 Saint-Genis-Laval, France; Observatoire de Genève, Université de Genève , 51 Ch. des Maillettes, 1290 Versoix, SwitzerlandDepartment of Astronomy, University of Massachusetts Amherst , Amherst, MA 01002, USAObservatoire de Genève, Université de Genève , 51 Ch. des Maillettes, 1290 Versoix, SwitzerlandStockholm University, Department of Astronomy and Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre , SE-10691, Stockholm, SwedenKapteyn Astronomical Institute, University of Groningen , P.O Box 800, 9700 AV Groningen, The NetherlandsUltraviolet absorption line spectroscopy is a sensitive diagnostic for the properties of interstellar and circumgalactic gas. Down-the-barrel observations, where the absorption is measured against the galaxy itself, are commonly used to study feedback from galactic outflows and to make predictions about the leakage of H i ionizing photons into the intergalactic medium. Nonetheless, the interpretation of these observations is challenging, and observational compromises are often made in terms of signal-to-noise ratio, spectral resolution, or the use of stacking analyses. In this paper, we present a novel quantitative assessment of UV absorption line measurement techniques by using mock observations of a hydrodynamical simulation. We use a simulated galaxy to create 22,500 spectra in the commonly used Si ii lines while also modeling the signal-to-noise ratio and spectral resolution of recent rest-frame UV galaxy surveys at both high and low redshifts. We show that the residual flux of absorption features is easily overestimated for single line measurements and for stacked spectra. Additionally, we explore the robustness of the partial covering model for estimating column densities from spectra and find underpredictions on an average of 1.25 dex. We show that the underprediction is likely caused by high-column-density sight lines that are optically thick to dust making them invisible in UV spectra.https://doi.org/10.3847/1538-4357/ad9b13Galactic windsGalaxy evolutionGalaxy spectroscopyUltraviolet astronomyUltraviolet spectroscopyHydrodynamical simulations |
| spellingShingle | R. Michael Jennings Alaina Henry Valentin Mauerhofer Timothy Heckman Claudia Scarlata Cody Carr Xinfeng Xu Mason Huberty Simon Gazagnes Anne E. Jaskot Jeremy Blaizot Anne Verhamme Sophia R. Flury Alberto Saldana-Lopez Matthew J. Hayes Maxime Trebitsch A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements The Astrophysical Journal Galactic winds Galaxy evolution Galaxy spectroscopy Ultraviolet astronomy Ultraviolet spectroscopy Hydrodynamical simulations |
| title | A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements |
| title_full | A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements |
| title_fullStr | A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements |
| title_full_unstemmed | A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements |
| title_short | A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements |
| title_sort | simulated galaxy laboratory exploring the observational effects on uv spectral absorption line measurements |
| topic | Galactic winds Galaxy evolution Galaxy spectroscopy Ultraviolet astronomy Ultraviolet spectroscopy Hydrodynamical simulations |
| url | https://doi.org/10.3847/1538-4357/ad9b13 |
| work_keys_str_mv | AT rmichaeljennings asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT alainahenry asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT valentinmauerhofer asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT timothyheckman asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT claudiascarlata asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT codycarr asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT xinfengxu asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT masonhuberty asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT simongazagnes asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT anneejaskot asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT jeremyblaizot asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT anneverhamme asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT sophiarflury asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT albertosaldanalopez asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT matthewjhayes asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT maximetrebitsch asimulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT rmichaeljennings simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT alainahenry simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT valentinmauerhofer simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT timothyheckman simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT claudiascarlata simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT codycarr simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT xinfengxu simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT masonhuberty simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT simongazagnes simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT anneejaskot simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT jeremyblaizot simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT anneverhamme simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT sophiarflury simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT albertosaldanalopez simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT matthewjhayes simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements AT maximetrebitsch simulatedgalaxylaboratoryexploringtheobservationaleffectsonuvspectralabsorptionlinemeasurements |