Neutron lifetime, dark matter and search for sterile neutrino

Abstract

A review is focused on experimental measurements on neutron lifetime. The latest measurements with a gravitational trap (PNPI NRC KI) and a magnetic trap (LANL, USA) confirmed PNPI result of 2005. The results of measurements with storage of ultra cold neutrons are in agreement, yet, there is discrepancy with a beam experiment by $3.5\sigma$ (1% of decay probability), which is discussed in literature as "neutron anomaly" along with the ideas of explaining it by decay into dark matter partially. The second part of the paper is devoted to so called "reactor antineutrino anomaly", which refers to deficiency of the measured flux of antineutrino from reactor in respect to the calculated flux by $3\sigma$(deviation by 6.6%). Specific feature of the proposal in this paper lies in the fact that both anomalies can be accounted for by one and the same phenomenon of oscillation in baryon sector between a neutron and a neutron of dark matter $n\to n^{\prime }$ with mass $m_{n^{\prime }}$, somewhat less than mass $m_n$ of an ordinary neutron. Calculations of the proposed model require one free parameter: mass difference $m_n-m_{n^{\prime }}$ if one normalizes probability of oscillations for a free neutron on "neutron anomaly" 1%, then, having succeeded to interpret 6.6% of neutron anomaly in calculations, one can determine mass difference. According to preliminary estimations, the mass difference is $m_n-m_{n^{\prime }}\approx$ 3 MeV. However, the analysis of cumulative yields of isotopes occurs in fission fragments was performed and it does not confirm possibility of existence of additional decay channel with emission of dark matter neutron with mass difference $m_n-m_{n^{\prime }}\approx$ 3 MeV. The result of the analysis is the conclusion that for mirror neutrons the region of the mass difference $m_n-m_{n^{\prime }}\ge$ 3 MeV is closed. The region of the mass difference $m_n-m_{n^{\prime }}\le$ 2 MeV turned out to be not closed.

arXiv comment20 pages, 18 figures

References in corpus (8)

• Dark Matter Interpretation of the Neutron Decay Anomaly
• Measurement of the neutron lifetime using an asymmetric magneto- gravitational trap and in situ detection
• Search for the Neutron Decay n$\to$ X+$\gamma$ where X is a dark matter particle
• Revised neutrino-gallium cross section and prospects of BEST in resolving the Gallium anomaly
• IsoDAR@KamLAND: A Conceptual Design Report for the Technical Facility
• Neutrino Physics with Accelerator Driven Subcritical Reactors
• Measurement of the neutron lifetime with ultra-cold neutrons stored in a magneto-gravitational trap
• SoLid: Search for Oscillation with a 6Li Detector at the BR2 research reactor

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• Neutron to Dark Matter Decay in Neutron Stars
• Novel neutron decay mode inside neutron stars
• Simulating the weak death of the neutron in a femtoscale universe with near-Exascale computing
• Neutron lifetime beam anomaly and possible explanation