A Caltech Library Service

Core-collapse, evaporation, and tidal effects: the life story of a self-interacting dark matter subhalo

Zeng, Zhichao Carton and Peter, Annika H. G. and Du, Xiaolong and Benson, Andrew and Kim, Stacy and Jiang, Fangzhou and Cyr-Racine, Francis-Yan and Vogelsberger, Mark (2022) Core-collapse, evaporation, and tidal effects: the life story of a self-interacting dark matter subhalo. Monthly Notices of the Royal Astronomical Society, 513 (4). pp. 4845-4868. ISSN 0035-8711. doi:10.1093/mnras/stac1094.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Submitted Version
Creative Commons Attribution.


Use this Persistent URL to link to this item:


Self-interacting dark matter (SIDM) cosmologies admit an enormous diversity of dark matter (DM) halo density profiles, from low-density cores to high-density core-collapsed cusps. The possibility of the growth of high central density in low-mass haloes, accelerated if haloes are subhaloes of larger systems, has intriguing consequences for small-halo searches with substructure lensing. However, following the evolution of ≲ 10⁸ M_⊙ subhaloes in lens-mass systems (⁠∼10¹³ M_⊙⁠) is computationally expensive with traditional N-body simulations. In this work, we develop a new hybrid semi-analytical + N-body method to study the evolution of SIDM subhaloes with high fidelity, from core formation to core-collapse, in staged simulations. Our method works best for small subhaloes (≲1/1000 host mass), for which the error caused by dynamical friction is minimal. We are able to capture the evaporation of subhalo particles by interactions with host halo particles, an effect that has not yet been fully explored in the context of subhalo core-collapse. We find three main processes drive subhalo evolution: subhalo internal heat outflow, host-subhalo evaporation, and tidal effects. The subhalo central density grows only when the heat outflow outweighs the energy gain from evaporation and tidal heating. Thus, evaporation delays or even disrupts subhalo core-collapse. We map out the parameter space for subhaloes to core-collapse, finding that it is nearly impossible to drive core-collapse in subhaloes in SIDM models with constant cross-sections. Any discovery of ultracompact dark substructures with future substructure lensing observations favours additional degrees of freedom, such as velocity-dependence, in the cross-section.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Zeng, Zhichao Carton0000-0002-6008-5144
Peter, Annika H. G.0000-0002-8040-6785
Benson, Andrew0000-0001-5501-6008
Jiang, Fangzhou0000-0001-6115-0633
Cyr-Racine, Francis-Yan0000-0002-7939-2988
Vogelsberger, Mark0000-0001-8593-7692
Additional Information:© 2022 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 ( Received: 13 October 2021. Revision received: 18 April 2022. Accepted: 19 April 2022. Published: 25 April 2022. We thank Kimberly Boddy, Hai-Bo Yu, Akaxia Cruz, Sten Delos, Anthony Pullen, Shengqi Yang, Ethan Nadler, Ivan Esteban, Daniel Gilman, Leonidas Moustakas, Charles Mace, Ekapob Kulchoakrungsun, Birendra Dhanasingham, Lingyuan Ji, and Yueying Ni for useful discussions. This work was supported in part by the NASA Astrophysics Theory Program, under grant 80NSSC18K1014. MV acknowledges support through NASA Astrophysics Theory Program grants 16-ATP16-0167, 19-ATP19-0019, 19-ATP19-0020, 19-ATP19-0167, and National Science Foundation grants AST-1814053, AST-1814259, AST-1909831, and AST-2007355. Simulations in this work were conducted using the Pitzer Cluster (including the CCAPP condo) at the Ohio Supercomputing Center. DATA AVAILABILITY. The data supporting the plots within this article are available on reasonable request to the corresponding author.
Funding AgencyGrant Number
Subject Keywords:methods: numerical, galaxies: haloes, dark matter
Issue or Number:4
Record Number:CaltechAUTHORS:20220802-742860000
Persistent URL:
Official Citation:Zhichao Carton Zeng, Annika H G Peter, Xiaolong Du, Andrew Benson, Stacy Kim, Fangzhou Jiang, Francis-Yan Cyr-Racine, Mark Vogelsberger, Core-collapse, evaporation, and tidal effects: the life story of a self-interacting dark matter subhalo, Monthly Notices of the Royal Astronomical Society, Volume 513, Issue 4, July 2022, Pages 4845–4868,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:116018
Deposited By: George Porter
Deposited On:02 Aug 2022 21:14
Last Modified:02 Aug 2022 21:14

Repository Staff Only: item control page