Lopez Castro, Neutron
beta decay and the current determination of |[V.
The upshot of each beta decay is an atom with a nucleus that contains one more proton than it did before.
Ordinarily, a single beta decay permits a neutron to assume a less energetic state.
I have shown that a field-expansion spectrometer with a long drift distance to measure proton time of flight is an attractive approach to measure the electron-neutrino correlation in neutron
beta decay.
If this technique for detection of radiative neutron
beta decay proves fruitful, a more precise measurement of the photon spectrum should be possible.
Decay protons emitted from a neutron
beta decay have a maximum kinetic energy of [approximately equal to]750 eV.
In Section 3 we summarize the limits on the CPV
beta decay coupling constants implied by
beta decay experiments.
The
beta decay experiments that are searching for neutrino mass all use tritium, the heaviest, rarest and only radioactive isotope of hydrogen, which is also the simplest nucleus susceptible to
beta decay.
The chopper-closed part of the time-of-flight spectrum is used by the NPDGamma to study detector pedestals and
beta decay from neutron activation.
The combined neutron, gamma, and
beta decay heat load on the methane moderator is expected to be on the order of 1 W when the facility is operated at its full power of 30 kW.
The other 99 percent is uranium-238, which is not fissile but rather fertile; if it gains a neutron of the right energy, it turns into uranium-239, which after a couple of
beta decays becomes fissile plutonium-239.
The new, unexpected result is that so much energy escapes by neutrino emission that the remaining energy released in the
beta decays is not sufficient to ignite the X-ray superbursts that are observed.
