Millicharged Particle Constraints from Asymptotic Giant Branch Stars

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Fiorillo, Damiano F. G., Lucente, Giuseppe, Sakstein, Jeremy, Vitagliano, Edoardo
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914614822830080
author Fiorillo, Damiano F. G.
Lucente, Giuseppe
Sakstein, Jeremy
Vitagliano, Edoardo
author_facet Fiorillo, Damiano F. G.
Lucente, Giuseppe
Sakstein, Jeremy
Vitagliano, Edoardo
contents We investigate the effect of millicharged particles (MCPs) with electric charge $qe\ll e$ and mass $m_χ$ on the late-stage evolution phases of low-mass stars in globular clusters. We predict the $R_2$ parameter -- the ratio of the number of stars in the asymptotic giant branch (AGB) phase to the number of stars in the horizontal branch (HB) phase -- and compare it against globular cluster data. While the production of MCPs shortens both the HB and AGB lifetimes, a larger reduction in the AGB phase arises from the higher temperatures in the helium-burning shell. We find the strongest bounds in the range $10\,\mathrm{keV}\lesssim m_χ\lesssim 100\,\mathrm{keV}$, reaching charges as small as $q\simeq 5\times10^{-13}$ and surpassing existing constraints by up to two orders of magnitude.
format Preprint
id arxiv_https___arxiv_org_abs_2605_30422
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Millicharged Particle Constraints from Asymptotic Giant Branch Stars
Fiorillo, Damiano F. G.
Lucente, Giuseppe
Sakstein, Jeremy
Vitagliano, Edoardo
High Energy Physics - Phenomenology
Solar and Stellar Astrophysics
We investigate the effect of millicharged particles (MCPs) with electric charge $qe\ll e$ and mass $m_χ$ on the late-stage evolution phases of low-mass stars in globular clusters. We predict the $R_2$ parameter -- the ratio of the number of stars in the asymptotic giant branch (AGB) phase to the number of stars in the horizontal branch (HB) phase -- and compare it against globular cluster data. While the production of MCPs shortens both the HB and AGB lifetimes, a larger reduction in the AGB phase arises from the higher temperatures in the helium-burning shell. We find the strongest bounds in the range $10\,\mathrm{keV}\lesssim m_χ\lesssim 100\,\mathrm{keV}$, reaching charges as small as $q\simeq 5\times10^{-13}$ and surpassing existing constraints by up to two orders of magnitude.
title Millicharged Particle Constraints from Asymptotic Giant Branch Stars
topic High Energy Physics - Phenomenology
Solar and Stellar Astrophysics
url https://arxiv.org/abs/2605.30422