Heavy neutrino dark matter in the solar system

TL;DR

This paper models a neutrino-based dark matter halo around the sun, analyzing its consistency with planetary data and proposing a method to detect it via X-ray emissions from neutrino decay.

Contribution

It introduces a simple model of solar system dark matter composed of heavy neutrinos and evaluates its observational consistency and detection prospects.

Findings

Neutrino halo mass distribution aligns with planetary orbital data for neutrino masses below 16 keV/c^2.

The model cannot explain the Pioneer anomaly.

Proposes detecting the neutrino halo through X-ray emissions from neutrino decay.

Abstract

We study a simple model of dark matter that is gravitationally clustered around the sun in the form of a spherical halo of a degenerate gas of heavy neutrinos. It is shown that for neutrino masses $m_{\nu} \stackrel {\textstyle <}{\sim} 16~{\rm keV}/c^{2}$, the resulting matter distribution is consistent with the constraints on the mass excesses within the orbits of the outer planets, as obtained from astrometrical and the Pioneer 10/11 and Voyager 1/2 (Anderson et al. 1995) ranging data. However, the anomalous acceleration recently detected in the Pioneer 10/11 data that is approximately constant between 40 AU and 60 AU (Anderson et al. 1998; Turyshev et al. 1999) is incompatible with both our model and earlier Pioneer 10/11 ranging data for the outer planets. We then calculate the planetary and asteroidal perihelion shifts generated by such a neutrino halo. For $m_{\nu} \stackrel{\textstyle <}{\sim}16~{\rm keV}/c^{2}$, our results are consistent with the observational data on Mercury, Venus, Earth and Icarus.Finally, we propose to detect this neutrino halo directly with a dedicated experiment on Earth, observing the X-rays emitted in the radiative decay of the heavy neutrino into a light neutrino and a photon.