Hidden Sector Dark Matter with Global $U(1{)}_X$-symmetry and Fermi-LAT 130 GeV $\gamma$-ray Excess

Abstract

We suggest a dark matter scenario which could contribute the possible anomaly observed by Fermi-LAT $\gamma$-ray space telescope. It is based on the model recently proposed by Weinberg. In our scenario the gamma-ray line signal comes from the fermionic dark matter ($M_{\mathrm{DM}}=214$ GeV) annihilating into two light scalars with mass around 500 MeV which in turn decay into two neutral pions. Finally the pions can decay into two 130 GeV photons. The strong constraint from the direct detection leaves only the channel of the dark matter annihilation into two light scalars for both the relic density and the Fermi-LAT gamma-ray line signal. The resulting gamma-ray spectrum is rather broad and does not fit to the data perfectly, but the data also show there may be fluctuation in the spectrum. There is no associated $Z$-boson or Higgs boson production contrary to most other works where the signal comes from the loops of charged particles. The annihilation into the other SM particles are highly suppressed due to the small mixing from the direct detection. Future experiments with more data will give more clues on the possible scenarios.

5 pages, 2 figures; minor changes

References in corpus (4)

• Dark Matter Results from 225 Live Days of XENON100 Data
• Fermi 130 GeV gamma-ray excess and dark matter annihilation in sub-haloes and in the Galactic centre
• Three Exceptions for Thermal Dark Matter with Enhanced Annihilation to Gamma Gamma
• Annihilation of singlet fermionic dark matter into two photons

Cited by in corpus (7)

• Dark Matter and Global Symmetries
• Two Loop Neutrino Model and Dark Matter Particles with Global $B-L$ Symmetry
• Radiative Lepton Model and Dark Matter with Global $U(1{)}^{\prime }$ Symmetry
• Gravity-mediated (or Composite) Dark Matter Confronts Astrophysical Data
• Weinberg's Higgs portal confronting recent LUX and LHC results together with upper limits on B^+ and K^+ decay into invisibles
• Dark matter physics in neutrino specific two Higgs doublet model
• Addendum to "Invisible Higgs decay width versus dark matter direct detection cross section in Higgs portal dark matter models"