The shallow potential wells of star-forming dwarf galaxies make their surrounding circumgalactic and intergalactic medium (CGM/IGM) sensitive laboratories for studying the inflows and outflows thought to regulate galaxy evolution. We present new absorption-line measurements in quasar sight lines, probing within projected distances of <300 kpc from 91 star-forming field dwarf galaxies with a median stellar mass of logM(star)/M-circle dot approximate to 8.3 at 0.077 < z < 0.73, from the Cosmic Ultraviolet Baryon Survey (CUBS). In this redshift range, the CUBS quasar spectra cover a suite of transitions including H i, low, and intermediate metal ions (e.g., C ii, Si ii, C iii, and Si iii), and highly ionized O vi. This CUBS-Dwarfs survey enables constraints with samples nine times larger than past dwarf CGM/IGM studies with similar ionic coverage. We find that low and intermediate ionization metal absorption is rare around dwarf galaxies, consistent with previous surveys of local dwarfs. In contrast, highly ionized O vi is commonly observed in sight lines that pass within the virial radius of a dwarf, and O vi detection rates are nonnegligible at projected distances of 1-2x the virial radius. Based on these measurements, we estimate that the O vi-bearing phase of the CGM/IGM accounts for a dominant share of the metal budget of dwarf galaxies. The absorption kinematics suggest that a relatively modest fraction of the O vi-bearing gas is formally unbound. Together, these results imply that low-mass systems at z less than or similar to 1 effectively retain a substantial fraction of their metals within the nearby CGM and IGM.

Mishra, N., Johnson, S., Rudie, G., Chen, H., Schaye, J., Qu, Z., et al. (2024). The Cosmic Ultraviolet Baryon Survey (CUBS). IX. The Enriched Circumgalactic and Intergalactic Medium Around Star-forming Field Dwarf Galaxies Traced by O vi Absorption. THE ASTROPHYSICAL JOURNAL, 976(1) [10.3847/1538-4357/ad7b0a].

The Cosmic Ultraviolet Baryon Survey (CUBS). IX. The Enriched Circumgalactic and Intergalactic Medium Around Star-forming Field Dwarf Galaxies Traced by O vi Absorption

Cantalupo S.;
2024

Abstract

The shallow potential wells of star-forming dwarf galaxies make their surrounding circumgalactic and intergalactic medium (CGM/IGM) sensitive laboratories for studying the inflows and outflows thought to regulate galaxy evolution. We present new absorption-line measurements in quasar sight lines, probing within projected distances of <300 kpc from 91 star-forming field dwarf galaxies with a median stellar mass of logM(star)/M-circle dot approximate to 8.3 at 0.077 < z < 0.73, from the Cosmic Ultraviolet Baryon Survey (CUBS). In this redshift range, the CUBS quasar spectra cover a suite of transitions including H i, low, and intermediate metal ions (e.g., C ii, Si ii, C iii, and Si iii), and highly ionized O vi. This CUBS-Dwarfs survey enables constraints with samples nine times larger than past dwarf CGM/IGM studies with similar ionic coverage. We find that low and intermediate ionization metal absorption is rare around dwarf galaxies, consistent with previous surveys of local dwarfs. In contrast, highly ionized O vi is commonly observed in sight lines that pass within the virial radius of a dwarf, and O vi detection rates are nonnegligible at projected distances of 1-2x the virial radius. Based on these measurements, we estimate that the O vi-bearing phase of the CGM/IGM accounts for a dominant share of the metal budget of dwarf galaxies. The absorption kinematics suggest that a relatively modest fraction of the O vi-bearing gas is formally unbound. Together, these results imply that low-mass systems at z less than or similar to 1 effectively retain a substantial fraction of their metals within the nearby CGM and IGM.
Articolo in rivista - Articolo scientifico
Dwarf galaxies; Intergalactic medium; Circumgalactic medium; Astrophysics - Astrophysics of Galaxies
English
19-nov-2024
2024
976
1
149
none
Mishra, N., Johnson, S., Rudie, G., Chen, H., Schaye, J., Qu, Z., et al. (2024). The Cosmic Ultraviolet Baryon Survey (CUBS). IX. The Enriched Circumgalactic and Intergalactic Medium Around Star-forming Field Dwarf Galaxies Traced by O vi Absorption. THE ASTROPHYSICAL JOURNAL, 976(1) [10.3847/1538-4357/ad7b0a].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/535301
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