Saved in:
Bibliographic Details
Main Authors: Zhao, Yu, Benson, Andrew, Du, Xiaolong
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2507.07963
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909753181995008
author Zhao, Yu
Benson, Andrew
Du, Xiaolong
author_facet Zhao, Yu
Benson, Andrew
Du, Xiaolong
contents In fuzzy dark matter scenarios, the quantum wave nature of ultralight axion-like particles generates stochastic density fluctuations inside dark matter halos. These fluctuations, known as granules, perturb the orbits of subhalos and other orbiting bodies. While previous studies have simulated these effects using N-body techniques or modeled them statistically using diffusion approximations, we propose an alternative framework based on representing the perturbations as a Fourier series with random coefficients, which can be applied to individual orbits, not just populations. We extend the model to finite-size subhalos, identifying a critical length scale below which subhalos behave as point-mass particles. In contrast, larger subhalos exhibit suppressed perturbations from granules due to their extended mass profiles. Using FDM-Simulator, we validate our finite-size model by isolating granule accelerations and confirming their statistical effects on subhalo dynamics.
format Preprint
id arxiv_https___arxiv_org_abs_2507_07963
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A Semi-Analytic model for Effects of Fuzzy Dark Matter Granule Perturbations on Orbital Motion
Zhao, Yu
Benson, Andrew
Du, Xiaolong
Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
In fuzzy dark matter scenarios, the quantum wave nature of ultralight axion-like particles generates stochastic density fluctuations inside dark matter halos. These fluctuations, known as granules, perturb the orbits of subhalos and other orbiting bodies. While previous studies have simulated these effects using N-body techniques or modeled them statistically using diffusion approximations, we propose an alternative framework based on representing the perturbations as a Fourier series with random coefficients, which can be applied to individual orbits, not just populations. We extend the model to finite-size subhalos, identifying a critical length scale below which subhalos behave as point-mass particles. In contrast, larger subhalos exhibit suppressed perturbations from granules due to their extended mass profiles. Using FDM-Simulator, we validate our finite-size model by isolating granule accelerations and confirming their statistical effects on subhalo dynamics.
title A Semi-Analytic model for Effects of Fuzzy Dark Matter Granule Perturbations on Orbital Motion
topic Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
url https://arxiv.org/abs/2507.07963