CMB Constraints on Loop-Induced Decays of Leptophilic Dark Matter

Abstract

Leptophilic sub-MeV spin-zero dark matter (DM) decays into photons via one-loop processes, a scenario that has been in part overlooked in current literature. In this work, we provide updated and comprehensive upper limits on scalar, pseudo-scalar, and axion-like DM-electron couplings based on the latest NPIPE cosmic microwave background data from Planck. Our bounds on the couplings are not only competitive with astrophysical and terrestrial experiments, but outperform them in certain regions of parameter space. Notably, we present the most stringent limits to date on scalar DM with masses around a few keV and pseudo-scalar DM with masses between 100 eV and a few keV. Additionally, we explore, for the first time, the impact of implementing a cosmology-consistent treatment of energy deposition into the cosmic medium.

14 pages, 8 figures, v2: minor changes, matches published version

References in corpus (26)

• Array Programming with NumPy
• Light Dark Matter: Models and Constraints
• Stellar cooling bounds on new light particles: plasma mixing effects
• Search for New Physics in Electronic Recoil Data from XENONnT
• General Constraints on Dark Matter Decay from the Cosmic Microwave Background
• Cosmological constraints on exotic injection of electromagnetic energy
• Flavor probes of axion-like particles
• Cosmological parameters derived from the final (PR4) Planck data release
• Refined Bounds on MeV-scale Thermal Dark Sectors from BBN and the CMB
• New Constraints on Sterile Neutrino Dark Matter from $NuSTAR$ M31 Observations
• BBN And The CMB Constrain Neutrino Coupled Light WIMPs
• A deep search for decaying dark matter with XMM-Newton blank-sky observations
• Emission of Single and Few Electrons in XENON1T and Limits on Light Dark Matter
• Axions - Motivation, limits and searches
• Search for dark matter particle interactions with electron final states with DarkSide-50
• Strong supernovae bounds on ALPs from quantum loops
• Stellar limits on scalars from electron-nucleus bremsstrahlung
• Joint CMB and BBN Constraints on Light Dark Sectors with Dark Radiation
• Dark Matter Absorption via Electronic Excitations
• The first search for bosonic super-WIMPs with masses up to 1 MeV/c${}^2$ with GERDA
• CMB and Lyman-$\alpha$ constraints on dark matter decays to photons
• What does cosmology tell us about the mass of thermal-relic dark matter?
• Axion Dark Matter from Lepton flavor-violating Decays
• Exploring New Physics with PandaX-4T Low Energy Electronic Recoil Data
• Search for MeV-Scale Axionlike Particles and Dark Photons with PandaX-4T
• Interacting light thermal-relic dark matter: self-consistent cosmological bounds