Spectroscopic search for optical emission lines from dark matter decay

Journal Article · 11 November 2024 · Physical Review. D.

DOI: https://doi.org/10.1103/PhysRevD.110.103007 · OSTI ID:3007357

Wang, Hanyue  ^[1]; Eisenstein, Daniel J. ^[1]; Aguilar, Jessica Nicole  ^[2]; Ahlen, Steven  ^[3]; Bailey, Stephen ^[2]; Brooks, David ^[4]; Claybaugh, Todd ^[2]; de la Macorra, Axel  ^[5]; Doel, Peter ^[4]; Forero-Romero, Jaime E.  ^[6]; Kremin, Anthony  ^[2]; Levi, Michael E.  ^[2]; Manera, Marc  ^[7]; Miquel, Ramon ^[8]; Poppett, Claire ^[2]; Rezaie, Mehdi ^[9]; Rossi, Graziano ^[10]; Sanchez, Eusebio  ^[11]; Schubnell, Michael ^[12]; Tarlé, Gregory ^[12] ; Weaver, Benjamin A. ^[13]; Zhou, Zhimin  ^[14]

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1. Harvard University, Cambridge, MA (United States); Center for Astrophysics Harvard & Smithsonian, Cambridge, MA (United States)
2. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
3. Boston University, MA (United States)
4. University College London (United Kingdom)
5. Universidad Nacional Autónoma de México (Mexico)
6. Universidad de los Andes, Bogota (Colombia)
7. Universitat Autònoma de Barcelona (Spain); The Barcelona Institute of Science and Technology, Bellaterra Barcelona (Spain)
8. The Barcelona Institute of Science and Technology, Bellaterra Barcelona (Spain); Institució Catalana de Recerca i Estudis Avançats, Barcelona (Spain)
9. Kansas State University, Manhattan, KS (United States)
10. Sejong University, Seoul (Korea)
11. CIEMAT, Madrid (Spain)
12. University of Michigan, Ann Arbor, MI (United States)
13. NSF’s NOIRLab, Tucson, AZ (United States)
14. Chinese Academy of Sciences, Beijing (China)

We search for narrow-line optical emission from dark matter decay by stacking dark-sky spectra from the Dark Energy Spectroscopic Instrument (DESI) at the redshift of nearby galaxies from DESI’s Bright Galaxy and Luminous Red Galaxy samples. Our search uses regions separated by 5 to 20 arcsec from the centers of the galaxies, corresponding to an impact parameter of approximately 50 kpc. No unidentified spectral line shows up in the search, and we place a line flux limit of 10⁻¹⁹  ergs/s/cm²/arcsec² on emissions in the wavelength range of 2000–9000⁢ Å. This places the tightest constraints yet on the two-photon decay of dark matter in the mass range of 5 to 12 eV, with a particle lifetime exceeding 3 × 10²⁵ s. Furthermore, this detection limit also implies that the line surface brightness contributed from all dark matter along the line of sight is at least 2 orders of magnitude lower than the measured extragalactic background light (EBL), ruling out the possibility that narrow optical-line emission from dark matter decay is a major source of the EBL.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC); University of Michigan, Ann Arbor, MI (United States)
• Sponsoring Organization: National Science Foundation (NSF); U.S. National Science Foundation (NSF), Division of Astronomical Sciences; USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-05CH11231; SC0007881; SC0019193
• OSTI ID: 3007357
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 10 Vol. 110; ISSN 2470-0010; ISSN 2470-0029
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English