Search for the Radiative Decay of a Cosmic Relic Particle with IUE

摘要

The UV background at the absolute value of or = 45 deg was determined using low resolution large aperture IUE spectra. Apart from the identification of hot interstellar gas emission lines, a component of the continuum with a power law distribution was fitted to the spectrum, as expected from the decay of a primordial relic light particle. From this fit a candidate mass for the neutrino of 14.8 + or - 0.1 eV and a lifetime of 10 to the 16th power yr are obtained. The probability that statistical fluctuations could mimic this signal is estimated to be 2%. Implications of the results in terms of cosmology and particle physics are discussed.