Related papers: Limits on Tensor Coupling from Neutron $\beta$-Dec…
Experimental studies of neutron decay, $n\to pe\bar\nu$, exhibit two anomalies. The first is a 8.6(2.1)s, roughly $4\sigma$ difference between the average beam measured neutron lifetime, $\tau_n^\text{beam}=888.0(2.0)$s, and the more…
The aCORN experiment measures the neutron decay electron-antineutrino correlation ($a$-coefficient) using a novel method based on an asymmetry in proton time-of-flight for events where the beta electron and recoil proton are detected in…
We report the results of an improved determination of the triple correlation $D P \cdot(p_{e}\times p_{\nu})$ that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to…
We compute $\beta$-decay half-lives of isotonic nuclear chains located at neutron shell closures $N=50$, $82$, $126$ and $184$, which are of particular importance for the $r$-process nucleosynthesis, and study the role of first-forbidden…
The existing experimental evidence on the vector and axial-vector coupling constants, $G_V$ and $G_A$, for neutron $\beta$-decay exhibits two prominent problems: (i) the unitarity for the first row of the CKM matrix seems violated; (ii) one…
Capability of medium energy setup of a beta beam experiment to probe new physics contributions to neutrino-W and neutrino-Z couplings are investigated. We employ the effective lagrangian approach of Buchmuller and Wyler and obtain 95%…
The neutron $\beta$-decay asymmetry parameter $A_0$ defines the correlation between the spin of the neutron and the momentum of the emitted electron, which determines $\lambda=\frac{g_{A}}{g_{V}}$, the ratio of the axial-vector to vector…
The beta asymmetry parameter A for the pure Gamow-Teller decay of 114In is reported. The low temperature nuclear orientation method was combined with a GEANT4 based simulation code allowing for the first time to address in detail the…
We present a precision measurement of the axial-vector coupling constant $g_A$ in the decay of polarized free neutrons. For the first time, a pulsed cold neutron beam was used for this purpose. By this method, leading sources of systematic…
The experimental determination of V_{ud} from neutron beta decay requires accurate values of the neutron lifetime and the ratio of the weak axial-vector to vector coupling constants of the nucleon. The latter is derived from measurements of…
We describe an experiment that has set new limits on the time reversal invariance violating D coefficient in neutron beta-decay. The emiT experiment measured the angular correlation J . p_e x p_p using an octagonal symmetry that optimizes…
$\beta$-decay properties of nuclei are investigated within the relativistic nuclear energy density functional framework by varying the temperature and density, conditions relevant to the final stages of stellar evolution. Both thermal and…
Neutron and nuclear beta decay correlation coefficients are linearly sensitive to the exotic scalar and tensor interactions that are not included in the Standard Model. The proposed experiment will measure simultaneously 11 neutron…
We provide model-independent bounds on the rates of rare decays $\eta (\eta^\prime) \to \pi\pi$ based on experimental limits on the neutron electric dipole moment (nEDM). Starting from phenomenological $\eta(\eta^\prime) \pi\pi$ couplings,…
The Nab experiment will measure the ratio of the weak axial-vector and vector coupling constants $\lambda=g_A/g_V$ with precision $\delta\lambda/\lambda\sim3\times10^{-4}$ and search for a Fierz term $b_F$ at a level $\Delta b_F<10^{-3}$.…
Strong upper bounds are derived on certain product combinations of lepton nonconserving couplings in the minimal supersymmetric standard model with explicit $R$-parity violation. The input is information from rare leptonic decays of the…
The contribution of the R-parity violating minimal supersymmetric standard model to the neutron beta decay at the one-loop level is investigated. It is found that the baryon number and R-parity violating interactions contribute to the D…
We report on a new measurement of the neutron beta-asymmetry parameter $A$ with the instrument \perkeo. Main advancements are the high neutron polarization of $P = 99.7(1)%$ from a novel arrangement of super mirror polarizers and reduced…
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…
We examine constraints on a model with pure right-handed third generation charged couplings. The parameters of the right-handed mixing matrix and the right-handed coupling strength are constrained from semi-leptonic B decays, the mass…