J 2020

A Black Hole Feedback Valve in Massive Galaxies

VOIT, G.M., G.L. BRYAN, D. PRASAD, R. FRISBIE, Y. LI et. al.

Basic information

Original name

A Black Hole Feedback Valve in Massive Galaxies

Authors

VOIT, G.M., G.L. BRYAN, D. PRASAD, R. FRISBIE, Y. LI, M. DONAHUE, B.W. OSHEA, M. SUN and Norbert WERNER

Edition

Astrophysical Journal, Chicago, University of Chicago Press, 2020, 0004-637X

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

United States of America

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 5.874

Organization unit

Faculty of Science

UT WoS

000561546600001

Keywords in English

Early-type galaxies; Elliptical galaxies; Giant elliptical galaxies; Quenched galaxies; Red sequence galaxies; X-ray astronomy; Circumgalactic medium

Tags

Změněno: 15/2/2024 09:27, Mgr. Marie Šípková, DiS.

Abstract

V originále

Star formation in the universe's most massive galaxies proceeds furiously early in time but then nearly ceases. Plenty of hot gas remains available but does not cool and condense into star-forming clouds. Active galactic nuclei (AGNs) release enough energy to inhibit cooling of the hot gas, but energetic arguments alone do not explain why quenching of star formation is most effective in high-mass galaxies. In fact, optical observations show that quenching is more closely related to a galaxy's central stellar velocity dispersion (sigma(v)) than to any other characteristic. Here we show that high sigma(v) is critical to quenching because a deep central potential well maximizes the efficacy of AGN feedback. In order to remain quenched, a galaxy must continually sweep out the gas ejected from its aging stars. Supernova heating can accomplish this task as long as the AGN sufficiently reduces the gas pressure of the surrounding circumgalactic medium (CGM). We find that CGM pressure acts as the control knob on a valve that regulates AGN feedback and suggest that feedback power self-adjusts so that it suffices to lift the CGM out of the galaxy's potential well. Supernova heating then drives a galactic outflow that remains homogeneous if sigma(v) greater than or similar to 240 km s(-1). The AGN feedback can effectively quench galaxies with a comparable velocity dispersion, but feedback in galaxies with a much lower velocity dispersion tends to result in convective circulation and accumulation of multiphase gas within the galaxy.

Links

MUNI/I/0003/2020, interní kód MU
Name: MUNI Award in Science and Humanities 3 (Acronym: Space-Based High-Energy Astrophysics)
Investor: Masaryk University, MUNI Award in Science and Humanities 3, MASH - MUNI Award in Science and Humanities