# Updated Collider and Direct Detection Constraints on Dark Matter Models for the Galactic Center Gamma-Ray Excess

Utilizing an exhaustive set of simplified models, we revisit dark matter scenarios potentially capable of generating the observed Galactic Center gamma-ray excess, updating constraints from the LUX and PandaX-II experiments, as well as from the LHC and other colliders. We identify a variety of pseudoscalar mediated models that remain consistent with all constraints. In contrast, dark matter candidates which annihilate through a spin-1 mediator are ruled out by direct detection constraints unless the mass of the mediator is near an annihilation resonance, or the mediator has a purely vector coupling to the dark matter and a purely axial coupling to Standard Model fermions. All scenarios in which the dark matter annihilates through $t$-channel processes are now ruled out by a combination of the constraints from LUX/PandaX-II and the LHC.

**Comments:**19 pages, 8 figures

## Similar Publications

**Affiliations:**

^{1}NIKHEF, Amsterdam & Leiden U.,

^{2}NIKHEF, Amsterdam,

^{3}NIKHEF, Amsterdam,

^{4}Liverpool U., Dept. Math.

**Category:**High Energy Physics - Phenomenology

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