A Search for Dark Matter Lines at the Galactic Center with 14 Years of Fermi Data

Abstract

Dark matter (DM) in the Milky Way halo may annihilate or decay to photons, producing monochromatic gamma rays. We search for DM-induced spectral lines using 14 years of data from the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope ($\text{Fermi}$-LAT) between $10\mathrm{GeV}$ and $2\mathrm{TeV}$ in the inner Milky Way leveraging both the spatial and spectral morphology of an expected signal. We present new constraints as strong as $⟨\sigma v⟩\lesssim 6\times 10^{-30}{\mathrm{cm}}^3/\mathrm{s}$ for the two-to-two annihilations and $\tau \gtrsim 10^{30}\mathrm{s}$ for one-to-two decays, representing leading sensitivity between $10\mathrm{GeV}$ and $\sim$$500\mathrm{GeV}$. We consider the implications of our line-constraints on the Galactic Center Excess (GCE), which is a previously-observed excess of continuum $\sim$GeV gamma-rays that may be explained by DM annihilation. The Higgs portal and neutralino-like DM scenarios, which have been extensively discussed as possible origins of the GCE, are constrained by our work because of the lack of observed one-loop decays to two photons. More generally, we interpret our null results in a variety of annihilating and decaying DM models, such as neutralinos, gravitinos, and glueballs, showing that in many cases the line search is more powerful than the continuum, despite the continuum annihilation being at tree level.

29 pages, 37 figures, video abstract at https://youtu.be/MWy5zHtu18A

References in corpus (27)

• The Well-Tempered Neutralino
• Background model systematics for the Fermi GeV excess
• Search for squarks and gluinos with the ATLAS detector in final states with jets and missing transverse momentum using $\sqrt{s}=8$ TeV proton--proton collision data
• A Renormalizable Model for the Galactic Center Gamma Ray Excess from Dark Matter Annihilation
• Dwarf galaxy annihilation and decay emission profiles for dark matter experiments
• Dark Matter Spectra from the Electroweak to the Planck Scale
• WIMPs at the Galactic Center
• Gamma Ray Spectrum from Gravitino Dark Matter Decay
• High Energy Cosmic Rays from the Decay of Gravitino Dark Matter
• The Effective Hooperon
• Observations of M31 and M33 with the Fermi Large Area Telescope: a galactic center excess in Andromeda?
• Multimessenger constraints on the dark matter interpretation of the Fermi-LAT Galactic center excess
• Searches for supersymmetry using the MT2 variable in hadronic events produced in pp collisions at 8 TeV
• Search for invisible Higgs-boson decays in events with vector-boson fusion signatures using 139 ${\text{fb}}^{-1}$ of proton-proton data recorded by the ATLAS experiment
• Strong constraints on thermal relic dark matter from Fermi-LAT observations of the Galactic Center
• Prospects for Heavy WIMP Dark Matter with CTA: the Wino and Higgsino
• The last Complex WIMPs standing
• Dark matter or correlated errors: Systematics of the AMS-02 antiproton excess
• Class of Higgs-portal Dark Matter models in the light of gamma-ray excess from Galactic center
• Dark Matter Interpretation of the Fermi-LAT Observations Toward the Outer Halo of M31
• Two Higgs Doublet Dark Matter Portal
• Amplified J-factors in the Galactic Center for velocity-dependent darkmatter annihilation in FIRE simulations
• Search for associated production of a $Z$ boson with an invisibly decaying Higgs boson or dark matter candidates at $\sqrt{s}=13$ TeV with the ATLAS detector
• Annihilating Dark Matter Search with 12 Years of Fermi LAT Data in Nearby Galaxy Clusters
• The Race to Find Split Higgsino Dark Matter
• A Closer Look at CP-Violating Higgs Portal Dark Matter as a Candidate for the GCE
• Assessing the Impact of Hydrogen Absorption on the Characteristics of the Galactic Center Excess

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• Multi-Component Dark Matter from Minimal Flavor Violation
• Probing Non-Minimal Dark Sectors via the 21 cm Line at Cosmic Dawn
• Probing Leptophobic Dark Sectors via Gravitational Wave Signatures
• Constraining Gamma-ray Lines from Dark Matter Annihilation using Fermi-LAT and H.E.S.S. data
• Probing ALP-portal fermionic dark matter at the $e^{+}{e}^{-}$ colliders