Autor: |
Wilde, Matthew C., Tchernyshyov, Kirill, Werk, Jessica K., Tripp, Todd M., Burchett, Joseph N., Prochaska, J. Xavier, Tejos, Nicolas, Lehner, Nicolas, Bordoloi, Rongmon, O'Meara, John M., Tumlinson, Jason, Howk, J. Christopher |
Předmět: |
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Zdroj: |
Astrophysical Journal; 5/10/2023, Vol. 948 Issue 2, p1-13, 13p |
Abstrakt: |
We combine data sets from the CGM2 and CASBaH surveys to model a transition point, R cross, between circumgalactic and intergalactic media (CGM and IGM, respectively). In total, our data consist of 7244 galaxies at z < 0.5 with precisely measured spectroscopic redshifts, all having impact parameters of 0.01–20 comoving Mpc from 28 QSO sightlines with high-resolution UV spectra that cover H i Ly α. Our best-fitting model is a two-component model that combines a 3D absorber–galaxy cross-correlation function with a simple Gaussian profile at inner radii to represent the CGM. By design, this model gives rise to a determination of R cross as a function of galaxy stellar mass, which can be interpreted as the boundary between the CGM and IGM. For galaxies with 108 ≤ M ⋆/ M ⊙ ≤ 1010.5, we find that R cross(M ⋆) ≈ 2.0 ± 0.6 R vir. Additionally, we find excellent agreement between R cross(M ⋆) and the theoretically determined splashback radius for galaxies in this mass range. Overall, our results favor models of galaxy evolution at z < 0.5 that distribute T ≈ 104K gas to distances beyond the virial radius. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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