Fermionic dark matter with pseudo-scalar Yukawa interaction

Abstract

We consider a renormalizable extension of the standard model whose fermionic dark matter (DM) candidate interacts with a real singlet pseudo-scalar via a pseudo-scalar Yukawa term while we assume that the full Lagrangian is CP-conserved in the classical level. When the pseudo-scalar boson develops a non-zero vacuum expectation value, spontaneous CP-violation occurs and this provides a CP-violated interaction of the dark sector with the SM particles through mixing between the Higgs-like boson and the SM-like Higgs boson. This scenario suggests a minimal number of free parameters. Focusing mainly on the indirect detection observables, we calculate the dark matter annihilation cross section and then compute the DM relic density in the range up to $m_{\text{DM}}=300$ GeV. We then find viable regions in the parameter space constrained by the observed DM relic abundance as well as invisible Higgs decay width in the light of 125 GeV Higgs discovery at the LHC. We find that within the constrained region of the parameter space, there exists a model with dark matter mass $m_{\text{DM}}\sim 38$ GeV annihilating predominantly into $b$ quarks, which can explain the Fermi-LAT galactic gamma-ray excess.

21 pages, v2: text clarification, Feynman diagrams and some references added, version to appear in JCAP

References in corpus (13)

• Dark Matter Results from 225 Live Days of XENON100 Data
• Gauge Singlet Scalars as Cold Dark Matter
• Constraints on Dark Matter from Colliders
• The Tevatron at the Frontier of Dark Matter Direct Detection
• Hadronic Uncertainties in the Elastic Scattering of Supersymmetric Dark Matter
• Maverick dark matter at colliders
• Possible Evidence For Dark Matter Annihilation In The Inner Milky Way From The Fermi Gamma Ray Space Telescope
• Pre-launch estimates for GLAST sensitivity to Dark Matter annihilation signals
• Singlet fermionic dark matter
• LanHEP - a package for automatic generation of Feynman rules from the Lagrangian. Updated version 3.1
• Total Width of 125 GeV Higgs Boson
• Neutralino Dark Matter in Mirage Mediation
• A New Determination of the Spectra and Luminosity Function of Gamma-Ray Millisecond Pulsars

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• Review of LHC Dark Matter Searches
• A taste of dark matter: Flavour constraints on pseudoscalar mediators
• WIMPs at the Galactic Center
• Nonthermal Two Component Dark Matter Model for Fermi-LAT $\gamma$-ray excess and 3.55 keV X-ray Line
• SUSY Implications from WIMP Annihilation into Scalars at the Galactic Centre
• The interpretation for Galactic Center Excess and Electroweak Phase Transition in the NMSSM
• $SU(2{)}_X$ Vector DM and Galactic Center Gamma-Ray Excess
• Extending LHC Coverage to Light Pseudoscalar Mediators and Coy Dark Sectors
• Two-portal Dark Matter
• Dark matter properties implied by gamma ray interstellar emission models