B. M. Fisher, F. E. Wietfeldt, Tulane University
J. Byrne, University of Sussex
Beta-decay of the neutron into a proton, electron, and antineutrino
is occasionally accompanied by the emission of a photon. Despite decades
of detailed experimental studies of neutron beta-decay, this rare branch
of a fundamental weak decay has never been measured, while it has been
extensively investigated in more exotic systems. An experiment to study
the radiative beta-decay of the neutron is currently being developed for
the NG6 fundamental physics beam line at the NIST Center for Neutron Research.
The experiment will make use of the existing apparatus for the NIST Penning-trap
lifetime experiment, which can provide substantial background reduction
by providing an electron-proton coincidence trigger. Tests and design of
a detector for gamma rays in the 100 keV range are under development. The
need for a large solid-angle gamma ray detector that can operate in a strong
magnetic field and at low temperature has led us to consider scintillating
crystals in conjunction with avalanche photodiodes. The apparatus has been
installed at the the NG6 beam line, and tests have begun. We hope to have
the final photon detector array installed and the entire apparatus taking
data by Spring, 2004.
Presenting Author's information