% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@ARTICLE{Roy:646139,
author = {Roy, Sandip and Prabhu, Anirudh and Thompson, Christopher
and Witte, Samuel and Blanco, Carlos and Zhang, Jonathan},
title = {{S}earching for axion dark matter near relaxing magnetars},
journal = {Physical review / D},
volume = {113},
number = {4},
issn = {2470-0010},
address = {Ridge, NY},
publisher = {American Physical Society},
reportid = {PUBDB-2026-00739, arXiv:2505.20450. DESY-25-050},
pages = {043001},
year = {2026},
note = {cc-by, 38 pages, 13 figures},
abstract = {Axion dark matter passing through the magnetospheres of
magnetars can undergo hyperefficient resonant mixing with
low-energy photons, leading to the production of narrow
spectral lines that could be detectable on Earth. Since this
is a resonant process triggered by the spatial variation in
the photon dispersion relation, the luminosity and spectral
properties of the emission are highly sensitive to the
charge and current densities permeating the magnetosphere.
To date, a majority of the studies investigating this
phenomenon have assumed a perfectly dipolar magnetic field
structure with a near-field plasma distribution fixed to the
minimal charge-separated force-free configuration. While
this may be a reasonable treatment for the closed field
lines of conventional radio pulsars, the strong magnetic
fields around magnetars are believed to host processes that
drive strong deviations from this minimal configuration. In
this work, we study how realistic magnetar magnetospheres
impact the electromagnetic emission produced from axion dark
matter. Specifically, we construct charge and current
distributions that are consistent with magnetar observations
and use these to recompute the prospective sensitivity of
radio and submillimeter telescopes to axion dark matter. We
demonstrate that the two leading models yield vastly
different predictions for the frequency and amplitude of the
spectral line, indicating systematic uncertainties in the
plasma structure are significant. Finally, we discuss
various observational signatures that can be used to
differentiate the local plasma loading mechanism of an
individual magnetar, which will be necessary if there is
hope of using such objects to search for axions.},
cin = {T},
ddc = {530},
cid = {I:(DE-H253)T-20120731},
pnm = {DFG project G:(GEPRIS)390833306 - EXC 2121: Das
Quantisierte Universum II (390833306) / 611 - Fundamental
Particles and Forces (POF4-611)},
pid = {G:(GEPRIS)390833306 / G:(DE-HGF)POF4-611},
experiment = {EXP:(DE-MLZ)NOSPEC-20140101},
typ = {PUB:(DE-HGF)16},
eprint = {2505.20450},
howpublished = {arXiv:2505.20450},
archivePrefix = {arXiv},
SLACcitation = {$\%\%CITATION$ = $arXiv:2505.20450;\%\%$},
doi = {10.1103/glnt-t93q},
url = {https://bib-pubdb1.desy.de/record/646139},
}