Circumgalactic Pressure Profiles Indicate Precipitation-Limited Atmospheres for $M_* \sim 10^9$$-$$10^{11.5}\,M_\odot$

G. M. Voit; M. Donahue; F. Zahedy; H. -W. Chen; J. Werk; G. L. Bryan; B. W. O'Shea

doi:10.3847/2041-8213/ab2766

paper

Circumgalactic Pressure Profiles Indicate Precipitation-Limited Atmospheres for $M_{*} \sim 1 0^{9}$ $-$ $1 0^{11.5} M_{⊙}$

arXiv:1903.00084 · doi:10.3847/2041-8213/ab2766

Abstract

Cosmic gas cycles in and out of galaxies, but outside of galaxies it is difficult to observe except for the absorption lines that circumgalactic clouds leave in the spectra of background quasars. Using photoionization modeling of those lines to determine cloud pressures, we find that galaxies are surrounded by extended atmospheres that confine the clouds and have a radial pressure profile that depends on galaxy mass. Motivated by observations of the universe's most massive galaxies, we compare those pressure measurements with models predicting the critical pressure at which cooler clouds start to precipitate out of the hot atmosphere and rain toward the center. We find excellent agreement, implying that the precipitation limit applies to galaxies over a wide mass range.

arXiv commentAccepted to ApJ Letters (8 pages, 4 figures)

Circumgalactic Pressure Profiles Indicate Precipitation-Limited Atmospheres for $M_{*} \sim 1 0^{9}$ $-$ $1 0^{11.5} M_{⊙}$

Abstract

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Circumgalactic Pressure Profiles Indicate Precipitation-Limited Atmospheres for M∗​∼109−1011.5M⊙​

Abstract

References in corpus (35)

Cited by in corpus (27)

Circumgalactic Pressure Profiles Indicate Precipitation-Limited Atmospheres for $M_{*} \sim 1 0^{9}$ $-$ $1 0^{11.5} M_{⊙}$