As we will discuss below both these types of models predict light neutrinos capable of mediating double beta decay
rates in the [W.sub.L]-[W.sub.L] channel saturating the current experimental limits.
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
. I emphasize the discussion of statistical and systematic errors, but a precise measurement of a will lead to the determination of [G.sub.a]/[G.sub.v].
describes the many physics targets that can be reached by that experiment, ranging from neutrinoless double beta decay
to neutrino oscillations and supernova neutrinos.
Like all elementary particle decays to charged particles in the final state, the beta decay
of the free neutron has a radiative mode: n [right arrow] p + [e.sup.-] + [bar.v.sub.e] + [gamma].
Key words: dead layer; electronbackscattering event; neutron beta decay
; silicon detector.
Vogel, "Double beta decay
," Annual Review of Nuclear and Particle Science, vol.
Little "a" is the momentum correlation coefficient of the electron and antineutrino produced in neutron beta decay
. One among several correlation coefficients describing this decay, little "a" has the largest uncertainty, 4 %.
However, it can be probed in tritium beta decay
 or neutrinoless double beta decay
Most important for the neutrinoless double beta decay
are the decays of [sup.68]Ge and [sup.60]Co since Q values above [Q.sub.[beta][beta]] = 2039 keV occur in the chain, and the lifetimes are in the range of years.
Decay protons emitted from a neutron beta decay
have a maximum kinetic energy of [approximately equal to]750 eV.
In beta decay
, a neutron inside anatomic nucleus decays into a proton emitting an electron (which in radiology is often called a beta ray).
Winter, "Systematic decomposition of the neutrinoless double beta decay
operator," Journal of High Energy Physics, vol.