Custom-designed model of the 17-keV neutrino.

A simple model is constructed which satisfies all the laboratory, astrophysical, and cosmological constraints discussed recently by Caldwell and Langacker for the possible existence of a 17-keV neutrino. It is mainly {nu}{sub {tau}}, with {bar {nu}}{sub {mu}} as its pseudo-Dirac partner, whereas {nu}{sub {ital e}} is mainly a light pseudo-Dirac neutrino with an inert partner. The decay lifetime of the 17-keV neutrino is estimated to be 10 s or longer.