XXth International Conference on Neutrino Physics and Astrophysics
A.Derbin, O.Smirnov & V.Tretyak for BOREXINO collaboration
Search for Invisible Nucleon Decay Modes (N ->3nu, NN ->2nu) with
Prototype of the Borexino Detector
Results of background measurements with prototype of the
Borexino detector (CTF) were used to obtain upper limits on the
instability of nucleons with respect to decays into invisible channels
(disappearance, decays to neutrinos, maojorons, ...). The most
stringent experimental bounds were established tau(nn -> 2nu) > 4.5 x
10^25 yr, tau(n -> 3nu) > 3.1 x 10^25 yr, tau(p -> 3nu) > 1.2 x 10^26
yr and tau(pp -> 2nu) > 5.5 x 10^25 yr.