Laboratory Constraints on a 33.9 MeV/c^2 Isosinglet Neutrino: Status and Perspectives

Abstract

An anomaly in the time behaviour of the signals observed by the KARMEN Collaboration may be interpreted as the possible decay signature of a 33.9 MeV/c${}^2$ mainly sterile neutrino. This note discusses the parameter space still open for the mixing of this hypothetical particle with the neutrinos of known leptonic flavour, considering the experimental results which became available recently, as well as those to be expected from forthcoming measurements. It is concluded that if no positive signature is observed, the envisaged laboratory experiments are not expected to close enterily the parameter space of mixing amplitudes. However, a proper reassessment of the ALEPH upper bound on the ${\nu }_{\tau }$ neutrino mass including the possibility of $\tau$ flavour mixing, would certainly help in reducing the parameter space left open.

arXiv commentLaTeX file, 11 pages, one figure available on request

Cited by in corpus (7)

• Search for heavy neutrinos mixing with tau neutrinos
• Limits on the Mixing of Tau Neutrino to Heavy Neutrinos
• A supersymmetric solution to the KARMEN time anomaly
• Sterile neutrinos in tau lepton decays
• The KARMEN Time Anomaly: Search for a Neutral Particle of Mass 33.9 MeV in Pion Decay
• Search for a 33.9 MeV/c^2 Neutral Particle in Pion Decay
• Does the KARMEN time anomaly originate from a beam-correlated background?