A Caltech Library Service

Survival and mass growth of cold gas in a turbulent, multiphase medium

Gronke, Max and Oh, S. Peng and Ji, Suoqing and Norman, Colin (2022) Survival and mass growth of cold gas in a turbulent, multiphase medium. Monthly Notices of the Royal Astronomical Society, 511 (1). pp. 859-876. ISSN 0035-8711. doi:10.1093/mnras/stab3351.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Accepted Version
See Usage Policy.


Use this Persistent URL to link to this item:


Astrophysical gases are commonly multiphase and highly turbulent. In this work, we investigate the survival and growth of cold gas in such a turbulent, multiphase medium using three-dimensional hydrodynamical simulations. Similar to previous work simulating coherent flow (winds), we find that cold gas survives if the cooling time of the mixed gas is shorter than the Kelvin–Helmholtz time of the cold gas clump (with some weak additional Mach number dependence). However, there are important differences. Near the survival threshold, the long-term evolution is highly stochastic, and subject to the existence of sufficiently large clumps. In a turbulent flow, the cold gas continuously fragments, enhancing its surface area. This leads to exponential mass growth, with a growth time given by the geometric mean of the cooling and the mixing time. The fragmentation process leads to a large number of small droplets which follow a scale-free dN/dm ∝ m⁻² mass distribution, and dominate the area covering fraction. Thus, whilst survival depends on the presence of large ‘clouds’, these in turn produce a ‘fog’ of smaller droplets tightly coupled to the hot phase which are probed by absorption line spectroscopy. We show with the aid of Monte Carlo simulations that the simulated mass distribution emerges naturally due to the proportional mass growth and the coagulation of droplets. We discuss the implications of our results for convergence criteria of larger scale simulations and observations of the circumgalactic medium.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper ItemVideos
Gronke, Max0000-0003-2491-060X
Oh, S. Peng0000-0002-1013-4657
Ji, Suoqing0000-0001-9658-0588
Norman, Colin0000-0002-5222-5717
Additional Information:© 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model ( Accepted 2021 No v ember 15. Received 2021 October 28; in original form 2021 July 19. Published: 23 November 2021. We thank the organizers and participants of the KITP ‘Fundamentals of Gaseous Halos’ workshop and in particular discussions with Chad Bustard, Hitesh Kishore Das, Ryan Farber, Drummond Fielding, Joe Hennawi, Nir Mandelker, Evan Schneider, and Brent Tan. This research made use of ATHENA++ (Stone et al. 2020; Development Team 2021), FLASH (Fryxell et al. 2000), YT (Turk et al. 2011), MATPLOTLIB (Hunter 2007), NUMPY (Van Der Walt, Colbert & Varoquaux 2011), and SCIPY (Virtanen et al. 2020). We acknowledge support from NASA grant NNX17AK58G, 19-ATP19-0205, HST grant HST-AR-15039.003-A, and XSEDE grant TG-AST180036 the Texas Advanced Computing Center (TACC) of the University of Texas at Austin. MG was supported by NASA through HST-HF2-51409 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. This research was supported in part by the National Science Foundation under Grant No. NSF PHY-1748958. Data Availability: Data related to this work will be shared on reasonable request to the corresponding author.
Group:TAPIR, Walter Burke Institute for Theoretical Physics
Funding AgencyGrant Number
NASA Hubble FellowshipHST-HF2-51409
Subject Keywords:hydrodynamics – ISM: clouds – ISM: structure – galaxy: kinematics and dynamics –galaxies: evolution – galaxies: haloes
Issue or Number:1
Record Number:CaltechAUTHORS:20220503-883387900
Persistent URL:
Official Citation:Max Gronke, S Peng Oh, Suoqing Ji, Colin Norman, Survival and mass growth of cold gas in a turbulent, multiphase medium, Monthly Notices of the Royal Astronomical Society, Volume 511, Issue 1, March 2022, Pages 859–876,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:114566
Deposited By: Tony Diaz
Deposited On:04 May 2022 17:55
Last Modified:04 May 2022 17:55

Repository Staff Only: item control page