相关论文: Measurement of the Shape Factor for the Beta Decay…

We report the measurement of the $^{214}$Bi beta-decay spectrum to the ground state of $^{214}$Po using the XENONnT detector. This decay is classified as first-forbidden non-unique, for which theoretical predictions require detailed nuclear…

The electron spectra of the $\beta$ decays of $^{92}$Rb and $^{142}$Cs, key contributors to the reactor antineutrino spectrum, were measured at the IGISOL facility using radioactive beams of high isotopic purity. The shapes of the measured…

The ASPECT-BET (An sdd-SPECTrometer for BETa decay studies) project aims to develop a novel technique for the precise measurement of forbidden $\beta$ spectra in the 10 keV - 1 MeV range. This technique uses a Silicon Drift Detector (SDD)…

Measurements of $\beta$-spectral shapes is an important way to examine the effective value of the weak axial coupling $g_{\rm A}$. These stu\ dies focus specifically on forbidden non-unique $\beta^-$ transitions, as only in these cases is…

We report the first direct measurement of the $^{14}\text{O}$ superallowed Fermi $\beta$-decay $Q_{EC}$-value, the last of the so-called "traditional nine" superallowed Fermi $\beta$-decays to be measured with Penning trap mass…

The ground-state Gamow-Teller transition in the decay of 14O is strongly hindered and the electron spectrum deviates markedly from the allowed shape. A reanalysis of the only available data on this spectrum changes the branching ratio…

We present a new measurement of the branching ratio for the decay of $^{14}$O to the ground state of $^{14}$N. The experimental result, $\lambda _0/\lambda _{\rm total} = (4.934 \pm 0.040\kern 1pt{\rm (stat.)} \pm 0.061\kern 1pt{\rm…

We derive a simple analytical formula to describe the evolution of spectral index $\beta$ in the steep decay phase shaped by the curvature effect with assumption that the spectral parameters and Lorentz factor of jet shell is the same for…

Highly precise measurements of the $^{99}$Tc beta spectrum were performed in two laboratories using metallic magnetic calorimeters. Independent sample preparations, evaluation methods and analyses yield consistent results and the spectrum…

The correlation coefficients a, A, and B in neutron beta-decay are proportional to the ratio of the axial-vector to vector weak coupling constants, g_A/g_V, to leading recoil order. With the advent of the next generation of neutron decay…

A new measurement of the half-life of the positron emitter 10C has been made. The 10C decay belongs to the set of superallowed 0+ -> 0+ beta-decays whose Ft values offer stringent tests of the Conserved Vector Current (CVC) hypothesis and…

Highly forbidden $\beta$ decays provide a sensitive test to nuclear models in a regime in which the decay goes through high spin-multipole states, similar to the neutrinoless double-$\beta$ decay process. There are only 3 nuclei ($^{50}$V,…

A new critical survey of all world data on superallowed beta decays provides demanding tests of, and tight constraints on, the weak interaction. In confirmation of the conserved vector current (CVC) hypothesis, the vector coupling coupling…

Neutrinoless double beta decay ($0\nu\beta\beta$) is a yet unobserved nuclear process which would demonstrate Lepton Number violation, a clear evidence of beyond Standard Model physics. The process two neutrino double beta decay…

We present expressions for shape variables of B decay distributions in several different mass schemes, to order $\alpha_s^2\beta_0$ and (Lambda_{QCD}/mb)^3. Such observables are sensitive to the b quark mass and matrix elements in the heavy…

The standard model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the $\beta$ decay of the free neutron. We report on the RDK II experiment which measured the photon…

The retardation spectrometer aSPECT was built to measure the shape of the proton spectrum in free neutron decay with high precision. This allows us to determine the antineutrino electron angular correlation coefficient a. We aim for a…

We present a critical assessment of the calculation and uncertainty of the $^{214}$Pb $\to$ $^{214}$Bi ground state to ground state $\beta$ decay, the dominant source of background in liquid Xenon dark matter detectors, down to below 1 keV.…

The beta-ray angular correlations for the spin alignments of 8Li and 8B have been observed in order to test the conserved vector current (CVC) hypothesis. The alignment correlation terms were combined with the known beta-alpha-angular…

In recent years, interest in experimental studies of $\beta$-decay electron spectra -- often referred to as $\beta$ spectra -- has been growing. This is particularly true for $\beta$ transitions where the electron spectra are sensitive to…