Dark matter production via a non-minimal coupling to gravity. Issue 2 (1st February 2023)

• Record Type: Journal Article
• Authors: Lebedev, Oleg; Solomko, Timofey; Yoon, Jong-Hyun
• Is Part Of: Journal of cosmology and astroparticle physics. Volume 2023:Issue 2(2023)
• Publication Date: 2023-02-01
• Subjects: dark matter simulations -- dark matter theory -- physics of the early universe; Cosmology -- Periodicals; Astrophysics -- Periodicals; 523.0105
• DOI: 10.1088/1475-7516/2023/02/035
• Languages: English
• ISSNs: 1475-7516

Abstract

Abstract: We study postinflationary scalar dark matter production via its non-minimal coupling to gravity. During the inflaton oscillation epoch, dark matter is produced resonantly for a sufficiently large non-minimal coupling ξ ≳ 5. We find that backreaction on the curvature and rescattering effects typically become important for the values of ξ above 30, which invalidate simple estimates of the production efficiency. At large couplings, the dark matter yield becomes almost independent of ξ, signifying approximate quasi-equilibrium in the inflaton-dark matter system. Although the analysis gets complicated by the presence of apparent negative energy in the Jordan frame, this behaviour can be regularized by introducing mild dark matter self-interaction. Using lattice simulations, we delineate parameter space leading to the correct dark matter relic abundance.