A1 Journal article (refereed)
Can QCD axion stars explain Subaru HSC microlensing? (2021)

Schiappacasse, E. D., & Yanagida, T. T. (2021). Can QCD axion stars explain Subaru HSC microlensing?. Physical Review D, 104(10), Article 103020. https://doi.org/10.1103/PhysRevD.104.103020

JYU authors or editors

Publication details

All authors or editors: Schiappacasse, Enrico D.; Yanagida, Tsutomu T.

Journal or series: Physical Review D

ISSN: 2470-0010

eISSN: 2470-0029

Publication year: 2021

Publication date: 16/11/2021

Volume: 104

Issue number: 10

Article number: 103020

Publisher: American Physical Society (APS)

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1103/PhysRevD.104.103020

Publication open access: Openly available

Publication channel open access: Partially open access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/79273

Publication is parallel published: https://arxiv.org/abs/2109.13153

Abstract

A non-negligible fraction of the QCD axion dark matter may form gravitationally bound Bose Einstein condensates, which are commonly known as axion stars or axion clumps. Such astrophysical objects have been recently proposed as the cause for the single candidate event reported by Subaru Hyper Suprime-Cam (HSC) microlensing search in the Andromeda galaxy. Depending on the breaking scale of the Peccei-Quinn symmetry and the details of the dark matter scenario, QCD axion clumps may form via gravitational condensation during radiation domination, in the dense core of axion miniclusters, or within axion minihalos around primordial black holes. We analyze all these scenarios and conclude that the microlensing candidate detected by the Subaru HSC survey is likely not caused by QCD axion stars.

Keywords: particle physics; cosmology; astrophysics; dark matter; quantum chromodynamics

Contributing organizations

Related projects

Ministry reporting: Yes

Reporting Year: 2021

JUFO rating: 2