Derivative Portal Dark Matter

TL;DR

This work introduces Derivative Portal Dark Matter (DPDM), a DM candidate whose interaction with SM fermions is mediated by derivative couplings of massive vector bosons, making the direct-detection amplitude vanish at zero momentum transfer via a momentum-transfer dependence on $t$. The authors show a cancellation mechanism and present three UV-complete models that realize the derivative portal through loop-induced $Z$–$Z'$ kinetic mixing while keeping photon mixing suppressed. Phenomenology indicates viable parameter space in light of Planck relic density, Fermi-LAT indirect detection, and collider constraints, with resonant and coannihilation effects near $m_{Z'}/2$. The results establish a new DM portal that evades direct detection and naturally accommodates the relic abundance, opening avenues for further UV completions and connections to neutrino masses and precision electroweak tests.

Abstract

We propose a new kind of Dark Matter: Derivative Portal Dark Matter. This kind of Dark Matter connects to the Standard Model through a massive mediator, which links to the Standard Model in derivative form. The derivative of a mediator in momentum space corresponds to the mediated momentum, which vanishes in the zero momentum transfer limit. As a result, this kind of Dark Matter can evade stringent constraint from the Dark Matter direct detection while fitting the Dark Matter relic density observation naturally. We explore several UV complete models of this kind of Dark matter. What's more, we show that these models also survive from Dark Matter indirect detection and collider search.

Figures (6)

• Figure 1: DM-SM fermion scattering in the DPDM model
• Figure 2: Derivative portal originating from loop corrections.
• Figure 3: Kinetic mixing between $B_{\mu}$ and $X_{\mu}$.
• Figure 4: Constraints on the $\mathrm{SU}(2)_\mathrm{L}\times \mathrm{U}(1)_{Z^{\prime}}$ model. The blue lines are contours that saturate the Planck experiment Planck:2018vyg observation of DM relic density, while the lightblue area are excluded by the Planck experiment, and the yellow area are excluded by the DM indirect detection bounds from Fermi-LAT experiment Ambrogi:2018jqjFermi-LAT:2016uux .
• Figure 5: Direct detection and relic density constrains on the DPDM model with small $M_{\hat{Z}^{\prime}}$.