Related papers: Superallowed Fermi beta decay
We have set limits on contributions of scalar interactions to nuclear beta decay. A magneto-optical trap (MOT) provides a localized source of atoms suspended in space, so the low-energy recoiling nuclei can freely escape and be detected in…
The accuracy of $V_{ud}$ determinations from superallowed $\beta$ decays critically hinges on control over radiative corrections. Recently, substantial progress has been made on the single-nucleon, universal corrections, while…
Background: The superallowed beta-decay rates provide stringent constraints on physics beyond the Standard Model of particle physics. To extract crucial information about the electroweak force, small isospin-breaking corrections to the…
The neutrinoless double-$\beta$ decay is a hypothetical rare nuclear decay, which can be used for determining the neutrino-mass scale. The scheme to use this decay for determining the neutrino-mass scale is one of few limited methods…
The double-beta (2$\beta$)-decay is the rarest nuclear physics process, and its experimental half-lives (T$_{1/2}$) exceed the age of the Universe from nine to fourteen orders of magnitude. Double-beta decay was observed, and its half-life…
We explore the possibility that the weak interaction violates Lorentz, and in particular rotational, invariance in neutron and allowed nuclear beta decay. A broad class of Lorentz-violating effects is considered, in which the standard…
Nuclear super-allowed $\beta$ decay has been used to obtain tight limits on the value of the CKM matrix element $V_{ud}$ that is important for unitarity tests, and therefore important for tests of the standard model. Current requirements on…
The determinations of the Cabibbo angle from kaon, pion, $D$ and tau decays disagree with the one from super-allowed beta decays. The resulting $\approx 3\,\sigma$ deficit in first row (but also first column) CKM unitarity is known as the…
Recent progress in nuclear-structure theory has been dramatic. I describe recent and future applications of ab initio calculations and the generator coordinate method to double-beta decay. I also briefly discuss the old and vexing problem…
In recent years a number of correlation measurements in nuclear $\beta$ decay have been performed reaching a precision of the order of 1\% and below and it is expected that even higher precision will be reached in the near future. At these…
The half-life of \tsups{37}K has been measured to be $1.23651(94)~\mathrm{s}$, a value nearly an order of magnitude more precise than the best previously reported. The $\beta^+$ decay of \tsups{37}K occurs mainly via a superallowed branch…
We perform a Markov Chain Monte Carlo (MCMC) statistical analysis of a number of measured ground-state-to-ground-state single $\beta^+$/electron-capture and $\beta^-$ decays in the nuclear mass range A = 62 - 142. The corresponding…
Study of the neutrinoless $\beta\beta$ decay allows us to put a stringent limit on the effective neutrino Majorana mass, a quantity of fundamental importance. To test our ability to evaluate the nuclear matrix elements that govern the decay…
The mass of the electron-antineutrino can be determined in dedicated measurements of the $\beta$ spectral shape near the $\beta$ endpoint of a $\beta^-$ transition, with a low $Q$ value enhancing the sensitivity of the measurement. One such…
We review the status of ab initio calculations of allowed beta decays (both Fermi and Gamow-Teller), within the framework of the valence-space in-medium similarity renormalization group approach.
The precision of double-beta ($\beta\beta$) decay experimental half-lives and their uncertainties is reevaluated. A complementary analysis of the decay uncertainties indicates deficiencies due to small size of statistical samples, and…
Measurements of neutron beta decay observables required to determine $|V_{ud}|$ are reaching the 0.1% accuracy. In this paper we review the calculation of the decay rate of this process, discuss its relevant uncertainties, and obtain an…
We report results from an experiment designed to test the conserved vector current (CVC) hypothesis by measuring the shape of the $\beta$-decay spectrum for the allowed $0^+\rightarrow 1^+$ ground state decay of $^{14}$O. Measurements of…
We review the radiative corrections to superallowed Fermi transitions and neutron beta decay in the Standard Model, and their relevance for the universality of the Weak Interactions.
We report the first \textit{ab initio} calculation of the nuclear-structure-dependent radiative correction $ \delta_{ \mathrm{NS} } $ to the $ {}^{10}\mathrm{C} \rightarrow {}^{10}\mathrm{B} $ superallowed transition, computed with the…