Eur. Phys. J. A (2006) 27: 63-66
https://doi.org/10.1140/epja/i2006-08-008-7

Nuclear Physics in Astrophysics II

Searching for Majorana neutrinos with double beta decay and with beta beams

The Andrzej Soltan Institute for Nuclear Studies, 05-400, Otwock - Świerk, Poland

^* e-mail: sujkowsk@ipj.gov.pl

Received: 11 July 2005
Accepted: 20 December 2005
Published online: 14 March 2006

Abstract

The leading questions in today neutrino physics concern the transformation properties of neutrinos under charge conjugation, the lepton number conservation hypothesis and the values of neutrino masses. The answers can be obtained if the neutrinoless double beta decay, 0ν2β, is observed and its rate is measured. The mere observation of the process proves the Majorana nature of neutrinos as well as the violation of the lepton number conservation, while the rate is a sensitive measure of the neutrino mass. The search for this effect at present concerns mainly the double β^- decay. This paper describes the recent proposal to search for the neutrinoless radiative double electron capture as an attractive alternative to the double β^- decay. It is shown, moreover, that the same information which is expected from the 0ν2β studies can in principle be also obtained from experiments using intense ν_e beams produced by radioactive ions decaying in flight (the “beta beams”).