Hunting Dark Matter Lines in the Infrared Background with the James Webb Space Telescope

Journal Article · 18 February 2025 · Physical Review Letters

DOI: https://doi.org/10.1103/physrevlett.134.071002 · OSTI ID:2228307

Janish, Ryan  ^[1]; Pinetti, Elena  ^[2]

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1. Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
2. Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Univ. of Chicago, IL (United States). Kavli Inst. for Cosmological Physics (KICP)

Dark matter particles with a mass around 1 eV can decay into near-infrared photons. Utilising available public blank sky observations from the NIRSpec IFU on the James Webb Space Telescope (JWST), we search for a narrow emission line due to decaying dark matter and derive leading constraints in the mass range 0.8-3 eV on the decay rate to photons, and more specifcally, on the axion-photon coupling for the case of axion-like particles. We exclude τ < 3.5 x 10²⁶ s at m_DM ≃ 0.8 eV and, in the case of axions, g_aγγ > 1.3 x 10^-11 GeV^-1 for m_a ≃ 2.2 eV. Our results do not rely on dedicated observations, rather we use blank sky observations intended for sky subtraction, and thus our reach may be automatically strengthened as JWST continues to observe.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: 89243024CSC000002; AC02-07CH11359
• OSTI ID: 2228307
• Report Number(s): FERMILAB-PUB--23-633-T; arXiv:2310.15395; oai:inspirehep.net:2714223
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 7 Vol. 134; ISSN 0031-9007
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English