Dark Matter Coherent Freeze-Out Mechanism: A Comprehensive Analysis
Abstract
Both Weakly-Interacting Massive Particle (WIMP) and Axion-Like Particle (ALP) are attractive particle dark matter candidates. In this paper we consider a scenario in which both WIMP and ALP are present. The two species interact via a non-derivative quadratic coupling modeled on the axion-nucleon interaction in QCD. We show that even a small (Planck-suppressed) coupling can drastically modify the cosmological history of both species. In the very early Universe, the ALP field acquires a vacuum expectation value, and the system undergoes an inverse phase transition at a temperature around or below the weak scale. WIMPs may remain in equilibrium far beyond the usual freeze-out time, eventually decoupling via a novel "coherent freeze-out" mechanism. WIMP annihilation cross sections several orders of magnitude above the canonical thermal target value can be consistent with the observed relic density in the coherent freeze-out scenario. At the same time, coherent oscillations of the ALP field do not begin until after the phase transition, and the initial conditions for these oscillations are set by the thermal physics of the phase transition. The ALP relic density is then predicted unambiguously in terms of the WIMP mass and coupling. We term this scenario "ALP miracle", since the observed relic density is obtained when these parameters are around their natural values, the weak and the Planck scale. The ALP miracle scenario prefers the ALP mass above about 10−3 eV, far larger than other popular ALP dark matter models. The ALP miracle parameter space overlaps with a currently allowed region of the QCD axion band, a large fraction of which is expected to be probed by the proposed IAXO experiment.
Related
- Kaon Portal to Freeze-in Dark Matter
- Hadrophilic inelastic freeze-in dark matter in q1−q2 gauge extension and the high energy LZ event
- Freeze-in of anapole and charge-radius inelastic dark matter: X-ray probes of a decoupled vector portal
- Radion/Dilaton portal freeze-in dark matter in extra-dimensional theories
- Probing freeze-in dark matter using Bose-Einstein condensate in neutron star
BibTeX
@misc{ferrante2026dark,
title = {{Dark Matter Coherent Freeze-Out Mechanism: A Comprehensive Analysis}},
author = {Steven Ferrante and Lillian Luo and Maxim Perelstein and Bingrong Yu},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.36049},
eprint = {2610.36049},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.36049},
}
RIS
TY - UNPB
TI - Dark Matter Coherent Freeze-Out Mechanism: A Comprehensive Analysis
AU - Steven Ferrante
AU - Lillian Luo
AU - Maxim Perelstein
AU - Bingrong Yu
PY - 2026
DA - 2026/10/26
PB - arXiv
DO - 10.48550/arxiv.2610.36049
UR - https://arxiv.org/abs/2610.36049
AB - Both Weakly-Interacting Massive Particle (WIMP) and Axion-Like Particle (ALP) are attractive particle dark matter candidates. In this paper we consider a scenario in which both WIMP and ALP are present. The two species interact via a non-derivative quadratic coupling modeled on the axion-nucleon interaction in QCD. We show that even a small (Planck-suppressed) coupling can drastically modify the cosmological history of both species. In the very early Universe, the ALP field acquires a vacuum expectation value, and the system undergoes an inverse phase transition at a temperature around or below the weak scale. WIMPs may remain in equilibrium far beyond the usual freeze-out time, eventually decoupling via a novel "coherent freeze-out" mechanism. WIMP annihilation cross sections several orders of magnitude above the canonical thermal target value can be consistent with the observed relic density in the coherent freeze-out scenario. At the same time, coherent oscillations of the ALP field do not begin until after the phase transition, and the initial conditions for these oscillations are set by the thermal physics of the phase transition. The ALP relic density is then predicted unambiguously in terms of the WIMP mass and coupling. We term this scenario "ALP miracle", since the observed relic density is obtained when these parameters are around their natural values, the weak and the Planck scale. The ALP miracle scenario prefers the ALP mass above about 10^−3 eV, far larger than other popular ALP dark matter models. The ALP miracle parameter space overlaps with a currently allowed region of the QCD axion band, a large fraction of which is expected to be probed by the proposed IAXO experiment.
ER -