Pith. sign in

REVIEW 5 cited by

Axion Clouds around Neutron Stars

Not yet reviewed by Pith; the record is open.

Re-run · record.json Download PDF Read on arXiv ↗

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2307.11811 v2 pith:YHIHLSTT submitted 2023-07-21 hep-ph astro-ph.CO

Dion Noordhuis , Anirudh Prabhu , Christoph Weniger , Samuel J. Witte This is my paper · ORCID
classification hep-phastro-ph.CO
keywords axioncloudaroundaxion-photonaxionsdensitieslesssimmasses
verification ladder T0 review T1 audit T2 compute T3 formal
0 comments
abstract

Recent work has shown that axions can be efficiently produced via non-stationary pair plasma discharges in the polar cap region of pulsars. Here, we point out that for axion masses $10^{-9} \, {\rm eV} \lesssim m_a \lesssim 10^{-4} \, \rm eV$, a sizable fraction of the sourced axion population will be gravitationally confined to the neutron star. These axions accumulate over astrophysical timescales, thereby forming a dense `axion cloud' around the star. We argue that the existence of such a cloud, with densities reaching and potentially exceeding $\mathcal{O}(10^{22}) \, {\rm GeV \, cm^{-3}}$, is a generic expectation across a wide range of parameter space. For axion masses $m_a \gtrsim 10^{-7} \, \rm eV$, energy is primarily radiated from the axion cloud via resonant axion-photon mixing, generating a number of distinctive signatures that include: a sharp line in the radio spectrum of each pulsar (located at the axion mass, and with an order percent-level width), and transient events arising from the reconfiguration of charge densities in the magnetosphere. While a deeper understanding of the systematic uncertainties in these systems is required, our current estimates suggest that existing radio telescopes could improve sensitivity to the axion-photon coupling by more than an order of magnitude.

Discussion (0). Continue with ORCID to comment.

Forward citations

Cited by 5 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. Resonant axion and dark photon production in magnetic white dwarfs

    hep-ph 2025-09 conditional novelty 7.0 of 10

    Magnetic fields broaden the resonant conversion of photons to axions and dark photons inside magnetic white dwarfs, enabling emission where none occurred before.

  2. Searching for Axion Dark Matter Near Relaxing Magnetars

    hep-ph 2025-05 conditional novelty 6.0 of 10

    Resonant axion-to-photon conversion near magnetars could be observable with ALMA and SKA, but the predicted line strength and frequency depend heavily on which plasma model is correct.

  3. Properties of QCD axion in two-flavor color superconductive matter with massive quarks

    hep-ph 2025-01 conditional novelty 6.0 of 10

    In a two-flavor NJL model with chiral and diquark condensates, the axion mass and quartic coupling increase at the chiral phase transition when color superconductivity is present.

  4. Gamma Rays from ALP-Photon Conversion and Inverse Compton Reprocessing in Neutron Star Magnetospheres

    astro-ph.HE 2026-08 conditional novelty 5.0 of 10

    ALP-to-photon conversion near four pulsars produces mostly sub-MeV emission: Fermi-LAT is insensitive to the channel, COMPTEL data already exclude new parameter space at high ALP mass, and COSI could probe much more.

  5. Probing Neutron Star Interiors and the Properties of Cold Ultra-dense Matter with the SKAO

    astro-ph.HE 2026-07 accept novelty 3.5 of 10

    SKAO's sensitivity, surveys and sub-arraying will deliver tighter NS mass, MoI, spin, glitch and precession constraints that, with X-ray and GW data, probe cold ultra-dense matter.

Pith tools