New Pathways to the Relic Abundance of Vector-Portal Dark Matter

Abstract

We fully explore the thermal freezeout histories of a vector-portal dark matter model, in the region of parameter space in which the ratio of masses of the dark photon $A^{\prime }$ and dark matter $\chi$ is in the range $1\lesssim m_{A^{\prime }}/m_{\chi }\lesssim 2$. In this region $2\to 2$ and $3\to 2$ annihilation processes within the dark sector, as well as processes that transfer energy between the dark sector and the Standard Model, play important roles in controlling the thermal freezeout of the dark matter. We carefully track the temperatures of all species, relaxing the assumption of previous studies that the dark and Standard Model sectors remain in thermal equilibrium throughout dark matter freezeout. Our calculations reveal a rich set of novel pathways which lead to the observed relic density of dark matter, and we develop a simple analytic understanding of these different regimes. The viable parameter space in our model provides a target for future experiments searching for light (MeV-GeV) dark matter, and includes regions where the dark matter self-interaction cross section is large enough to affect the small-scale structure of galaxies.

36 pages, 18 figures, comments welcome

References in corpus (16)

• Results from a search for dark matter in the complete LUX exposure
• SENSEI: Direct-Detection Results on sub-GeV Dark Matter from a New Skipper-CCD
• The effects of He I 10830 on helium abundance determinations
• Exciting Dark Matter and the INTEGRAL/SPI 511 keV signal
• Search for $A^{\prime }\to {\mu }^{+}{\mu }^{-}$ decays
• Constraints on sub-GeV hidden sector gauge bosons from a search for heavy neutrino decays
• US Cosmic Visions: New Ideas in Dark Matter 2017: Community Report
• Constraints on low-mass, relic dark matter candidates from a surface-operated SuperCDMS single-charge sensitive detector
• Refined Bounds on MeV-scale Thermal Dark Sectors from BBN and the CMB
• Results of Dark Matter Search using the Full PandaX-II Exposure
• Determination of the primordial helium abundance based on NGC 346 an HII region of the Small Magellanic Cloud
• DRAKE: Dark matter Relic Abundance beyond Kinetic Equilibrium
• Hints, neutrino bounds and WDM constraints from SDSS DR14 Lyman-$\alpha$ and Planck full-survey data
• Dark Higgs Dark Matter
• From dwarf galaxies to galaxy clusters: Self-Interacting Dark Matter over 7 orders of magnitude in halo mass
• Dark Initial State Radiation and the Kinetic Mixing Portal

Cited by in corpus (16)

• Recycled Dark Matter
• Roadmap to Thermal Dark Matter Beyond the WIMP Unitarity Bound
• Forbidden Scalar Dark Matter and Dark Higgses
• Dark Moments for the Standard Model ?
• Dark Matter Freeze-out via Catalyzed Annihilation
• Portal Matter, Kinetic Mixing, and Muon $g-2$
• Dark matter transient annihilations in the early Universe
• A Snowmass Whitepaper: Dark Matter Production at Intensity-Frontier Experiments
• Relic density and temperature evolution of a light dark sector
• Bouncing Dark Matter
• Indirect searches for realistic sub-GeV Dark Matter models
• Strong Constraints on Dark Photon and Scalar Dark Matter Decay from INTEGRAL and AMS-02 data
• Constraining the Secluded and Catalyzed Annihilation Dark Matter with Fermi-LAT and Planck Data
• Reviving $Z^{\prime }$ Portal Dark Matter with Conversion Mechanism
• Naturally Resonant Dark Matter from Extra Dimensions
• Probing inelastic sub-GeV dark matter at the DUNE near detector