Stringent neutrino flux constraints on anti-quark nugget dark matter

TL;DR

This paper investigates anti-quark nugget dark matter models, calculating neutrino fluxes from their interactions with Earth and Sun, and finds current neutrino observations impose strong constraints on their viability as dark matter candidates.

Contribution

It provides the first detailed neutrino flux calculations for anti-quark nugget dark matter and compares these with Super-Kamiokande limits to constrain such models.

Findings

Conventional anti-quark nuggets cannot make up more than 20% of dark matter.

Color-superconducting phase nuggets require suppressed muon production to remain viable.

Current neutrino flux limits strongly restrict anti-quark nugget dark matter scenarios.

Abstract

Strongly-interacting matter in the form of nuggets of nuclear-density material are not currently excluded as dark matter candidates in the ten gram to hundred kiloton mass range. A recent variation on quark nugget dark matter models postulates that a first-order imbalance between matter and antimatter in the quark-gluon plasma prior to hadron production in the early universe binds up most of the dark matter into heavy (baryon number $B \sim 10^{25}$) anti-quark nuggets in the current epoch, explaining both the dark matter preponderance and the matter-antimatter asymmetry. Interactions of these massive objects with normal matter in the Earth and Sun will lead to annihilation and an associated neutrino flux in the $\sim 20-50$ MeV range. We calculate these fluxes for anti-quark nuggets of sufficient number density to account for the dark matter and find that current neutrino flux limits from Super-Kamiokande provide stringent constraints on several possible scenarios for such objects. Conventional anti-quark nuggets in the previously allowed mass range cannot account for more than $\sim 1/5$ of the dark matter flux; if they are in a color-superconducting phase, then their muon production during matter annihilation must be suppressed by an order of magnitude below prior estimates if they are to remain viable dark matter candidates.