# Strongly Interacting Neutrino Portal Dark Matter

## TL;DR

This paper introduces a natural, simple model of strongly-interacting dark matter via the neutrino-portal, where dark photons mediate interactions, producing core-like galactic DM distributions while avoiding bound state formation and experimental constraints.

## Contribution

It proposes a novel neutrino-portal dark matter model with suppressed mixing and interactions, explaining galactic cores and evading key experimental bounds without fine-tuning.

## Key findings

- Dark matter interactions produce core-like galactic distributions.
- Dark photon mixing is suppressed, avoiding nucleosynthesis constraints.
- Nucleon scattering occurs only at one loop, reducing direct detection signals.

## Abstract

We present a realistic, simple and natural model of strongly-interacting dark matter based on the neutrino-portal paradigm. The strong interactions at small velocities are generated by the exchange of dark photons, and produce the observed core-like DM distribution in galactic centers; this effect could be spoiled by the formation of DM bound states (also due to dark-photon effects), which we avoid by requiring the DM candidates to be light, with masses below O(10 GeV). The mixing of the dark photon with the Z and ordinary photon is strongly suppressed by introducing a softly-broken discrete symmetry similar to charge conjugation, which also ensures that the dark photon life-time is short enough to avoid restrictions derived form big-bang nucleosynthesis and large-scale structure formation. Other constraints are accommodated without the need of fine tuning, in particular nucleon scattering occurs only at one loop, so direct detection cross sections are naturally suppressed. Neutrino masses are generated through the inverse see saw.