Stringent Constraints on Self-Interacting Dark Matter Using Milky-Way Satellite Galaxies Kinematics

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ando, Shin'ichiro, Hayashi, Kohei, Horigome, Shunichi, Ibe, Masahiro, Shirai, Satoshi
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916655274131456
author Ando, Shin'ichiro
Hayashi, Kohei
Horigome, Shunichi
Ibe, Masahiro
Shirai, Satoshi
author_facet Ando, Shin'ichiro
Hayashi, Kohei
Horigome, Shunichi
Ibe, Masahiro
Shirai, Satoshi
contents Self-interacting dark matter (SIDM) has been proposed to address small-scale challenges faced by the cold dark matter (CDM) paradigm, such as the diverse density profiles observed in dwarf galaxies. In this study, we analyze the kinematics of dwarf galaxies by incorporating the effects of gravothermal core collapse into SIDM models using a semi-analytical subhalo framework. Our analysis covers the stellar kinematics of both classical and ultrafaint dwarf galaxies. The results indicate a bimodal preference for small and large self-interaction cross sections in ultrafaint dwarf galaxies, while in classical dwarfs, larger cross sections progressively decrease the model's statistical support. The combined analysis decisively prefers CDM to SIDM when the self-interaction cross section per unit mass, $σ/m$, exceeds $\sim$0.2 cm$^2$/g, if a velocity-independent cross section is assumed. Our study significantly enhances our understanding of dark matter dynamics on small scales.
format Preprint
id arxiv_https___arxiv_org_abs_2503_13650
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Stringent Constraints on Self-Interacting Dark Matter Using Milky-Way Satellite Galaxies Kinematics
Ando, Shin'ichiro
Hayashi, Kohei
Horigome, Shunichi
Ibe, Masahiro
Shirai, Satoshi
Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
Self-interacting dark matter (SIDM) has been proposed to address small-scale challenges faced by the cold dark matter (CDM) paradigm, such as the diverse density profiles observed in dwarf galaxies. In this study, we analyze the kinematics of dwarf galaxies by incorporating the effects of gravothermal core collapse into SIDM models using a semi-analytical subhalo framework. Our analysis covers the stellar kinematics of both classical and ultrafaint dwarf galaxies. The results indicate a bimodal preference for small and large self-interaction cross sections in ultrafaint dwarf galaxies, while in classical dwarfs, larger cross sections progressively decrease the model's statistical support. The combined analysis decisively prefers CDM to SIDM when the self-interaction cross section per unit mass, $σ/m$, exceeds $\sim$0.2 cm$^2$/g, if a velocity-independent cross section is assumed. Our study significantly enhances our understanding of dark matter dynamics on small scales.
title Stringent Constraints on Self-Interacting Dark Matter Using Milky-Way Satellite Galaxies Kinematics
topic Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
url https://arxiv.org/abs/2503.13650