3.55 keV photon lines from axion to photon conversion in the Milky Way and M31

Abstract

We further explore a scenario in which the recently observed 3.55 keV photon line arises from dark matter decay to an axion-like particle (ALP) of energy 3.55 keV, which then converts to a photon in astrophysical magnetic fields. This ALP scenario is well-motivated by the observed morphology of the 3.55 keV flux. For this scenario we study the expected flux from dark matter decay in the galactic halos of both the Milky Way and Andromeda (M31). The Milky Way magnetic field is asymmetric about the galactic centre, and so the resulting 3.55 keV flux morphology differs significantly from the case of direct dark matter decay to photons. However the Milky Way magnetic field is not large enough to generate an observable signal, even with ASTRO-H. In contrast, M31 has optimal conditions for ALP to photon conversion and the intrinsic signal from M31 becomes two orders of magnitude larger than for the Milky Way, comparable to that from clusters and consistent with observations.

15 pages, 7 figures Version accepted for publication in JCAP

References in corpus (23)

• The Vertical Structure of Warm Ionised Gas in the Milky Way
• The Milky Way as a Kiloparsec-Scale Axionscope
• The Poker Face of the Majoron Dark Matter Model: LUX to keV Line
• Discovery of a 3.5 keV line in the Galactic Center and a Critical Look at the Origin of the Line Across Astronomical Targets
• Resonantly-Produced 7 keV Sterile Neutrino Dark Matter Models and the Properties of Milky Way Satellites
• The distribution of the ISM in the Milky Way A three-dimensional large-scale model
• The 7 keV axion dark matter and the X-ray line signal
• A 3.55 keV Photon Line and its Morphology from a 3.55 keV ALP Line
• X-ray line signal from decaying axino warm dark matter
• Generating X-ray lines from annihilating dark matter
• X-ray Lines from Dark Matter: The Good, The Bad, and The Unlikely
• Relic Gravity Waves and 7 keV Dark Matter from a GeV scale inflaton
• 3.5 keV X-rays as the "21 cm line" of dark atoms, and a link to light sterile neutrinos
• Anomaly-free flavor models for Nambu-Goldstone bosons and the 3.5 keV X-ray line signal
• keV Photon Emission from Light Nonthermal Dark Matter
• A Dynamical Framework for KeV Dirac Neutrino Warm Dark Matter
• 3.55 keV X-ray Line Signal from Excited Dark Matter in Radiative Neutrino Model
• Comment on the paper "Dark matter searches going bananas: the contribution of Potassium (and Chlorine) to the 3.5 keV line" by T. Jeltema and S. Profumo
• The 3.5 keV X-ray line signal from decaying moduli with low cutoff scale
• Cluster X-ray line at $3.5\mathrm{keV}$ from axion-like dark matter
• SUSY in the sky or a keV signature of sub-GeV gravitino dark matter
• 7 keV Dark Matter as X-ray Line Signal in Radiative Neutrino Model
• Natural $X$-ray Lines from the Low Scale Supersymmetry Breaking

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• Revised constraints and Belle II sensitivity for visible and invisible axion-like particles
• Discovery of a 3.5 keV line in the Galactic Center and a Critical Look at the Origin of the Line Across Astronomical Targets
• The Fermi Large Area Telescope as a Galactic Supernovae Axionscope
• Where do the 3.5 keV photons come from? A morphological study of the Galactic Center and of Perseus
• Tests of the CMB temperature-redshift relation, CMB spectral distortions and why adiabatic photon production is hard
• Axion-like Particles Implications for High-Energy Astrophysics
• Les Houches Lectures on Indirect Detection of Dark Matter
• A 3.55 keV line from $\text{DM}\to a\to \gamma$: predictions for cool-core and non-cool-core clusters
• Decaying Vector Dark Matter as an Explanation for the 3.5 keV Line from Galaxy Clusters
• Hidden axion dark matter decaying through mixing with QCD axion and the 3.5 keV X-ray line
• 3.5-keV X-ray line from nearly-degenerate WIMP dark matter decays
• Non-abelian Dark Matter Solutions for Galactic Gamma-ray Excess and Perseus 3.5 keV X-ray Line
• 3.5 keV X-ray line and R-Parity Conserving Supersymmetry
• ${\nu }_R$ dark matter-philic Higgs for 3.5 keV X-ray signal
• Observational consistency and future predictions for a 3.5 keV ALP to photon line
• 3.5 keV Galactic Emission Line as a Signal from the Hidden Sector
• Diffuse axion-like particle searches
• Searching for relativistic axions in the sky
• Testing the axion-conversion hypothesis of 3.5 keV emission with polarization
• An introduction to axions and their detection
• Photon Ring Dimming as a Signature of Photon-Axion Conversion in Janis-Newman-Winicour Naked Singularity