Dynamics and Frequency Conversion of Accreting Axion Clouds
Abstract
Axion fields can form exponentially growing gravitational clouds around compact objects through self-interaction-driven relaxation of ambient axion waves. As the field amplitude approaches the axion decay constant, nonlinear effects become important. We identify two distinct regimes of late-time evolution, determined by the gravitational fine-structure constant and the cloud growth rate: a Bosenova regime, characterized by collapse accompanied by explosive axion bursts, and a saturation regime, in which self-interaction-induced axion emission balances accretion. In the latter regime, the emitted axion radiation exhibits stable discrete spectral lines at odd multiples of the bound-state energy, directly probing the global structure of the axion potential beyond its quadratic minimum. We show that single-cosine potentials and QCD axion-like potentials predict distinct emission spectra, enabling probes of the underlying axion self-interaction structure and its ultraviolet completion through terrestrial detection of relativistic axion fluxes from compact objects.
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BibTeX
@misc{li2026dynamics,
title = {{Dynamics and Frequency Conversion of Accreting Axion Clouds}},
author = {Ximeng Li and Zhen Zhong and Yifan Chen and Yue Zhao and Hidetoshi Omiya and Vitor Cardoso},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.00128},
eprint = {2609.00128},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.00128},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Dynamics and Frequency Conversion of Accreting Axion Clouds
AU - Ximeng Li
AU - Zhen Zhong
AU - Yifan Chen
AU - Yue Zhao
AU - Hidetoshi Omiya
AU - Vitor Cardoso
PY - 2026
DA - 2026/09/01
PB - arXiv
DO - 10.48550/arxiv.2609.00128
UR - https://arxiv.org/abs/2609.00128
AB - Axion fields can form exponentially growing gravitational clouds around compact objects through self-interaction-driven relaxation of ambient axion waves. As the field amplitude approaches the axion decay constant, nonlinear effects become important. We identify two distinct regimes of late-time evolution, determined by the gravitational fine-structure constant and the cloud growth rate: a Bosenova regime, characterized by collapse accompanied by explosive axion bursts, and a saturation regime, in which self-interaction-induced axion emission balances accretion. In the latter regime, the emitted axion radiation exhibits stable discrete spectral lines at odd multiples of the bound-state energy, directly probing the global structure of the axion potential beyond its quadratic minimum. We show that single-cosine potentials and QCD axion-like potentials predict distinct emission spectra, enabling probes of the underlying axion self-interaction structure and its ultraviolet completion through terrestrial detection of relativistic axion fluxes from compact objects.
ER -