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Title: Cosmological structure formation and soliton phase transition in fuzzy dark matter with axion self-interactions

We investigate cosmological structure formation in fuzzy dark matter (FDM) with the attractive self-interaction (SI) with numerical simulations. Such a SI would arise if the FDM boson were an ultra-light axion, which has a strong CP symmetry-breaking scale (decay constant). Although weak, the attractive SI may be strong enough to counteract the quantum ‘pressure’ and alter structure formation. We find in our simulations that the SI can enhance small-scale structure formation, and soliton cores above a critical mass undergo a phase transition, transforming from dilute to dense solitons.

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Award ID(s):
2108962 1910346 1752913 2007355 2107724
Author(s) / Creator(s):
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Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Medium: X Size: p. 2608-2615
["p. 2608-2615"]
Sponsoring Org:
National Science Foundation
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