Related papers: Remarks on Delta Radiative and Dalitz Decays
The Dalitz decays eta -> e^+e^-g and omega -> pi^0 e^+e^- have been measured in the g p -> eta p and g p -> omega p reactions, respectively, with the A2 tagged-photon facility at the Mainz Microtron, MAMI. The value obtained for the slope…
We obtain predictions for $B_{(s)}\to e^+e^-\gamma$ and $B_{(s)}\to \mu^+\mu^-\gamma$ decays. All the contributions containing long-distance QCD effects are calculated in the framework of relativistic quark model. The contributions of the…
The three electromagnetic form factors of the $\Delta(1232)$ resonance, $G^*_M(q^2)$, $G^*_E(q^2)$, and $G^*_C(q^2)$ are obtained in the space-like region using a Dual Resonance Model realization of QCD in the large $N_c$ limit…
A precise comparison is made between the Dalitz decay $H\to\ell\bar{\ell}\gamma$ and the two body decay $H\to\gamma Z,Z\to\ell\bar{\ell}$ for electrons and for muons including experimental cuts appropriate for the ATLAS detector. The widths…
We study the decay properties of a heavy-light meson. We reformulate the decay amplitudes for the heavy-light systems and find a new way to calculate decay rates. Applying this formulation, we find a new sum rule for the radiative decays of…
Several methods for the treatment of pion photoproduction in the region of the Delta(1232) resonance are discussed, in particular the effective Lagrangian approach and the speed plot analysis are compared to a dynamical treatment. As a main…
We review the results of lattice QCD calculations of form factors for semileptonic decays of D and B mesons. We also mention results for semileptonic decays of b baryons and the rare radiative decay B to K* gamma.
We calculate the decay constant of $D_s$ and $D_s^{*}$ with $\bar{B}^0 \ra D^{+}\ell^{-}\nu$ and $\bar{B}^0 \ra D^{+}D_s^{-(*)}$ decays. In our analysis we assume that factorization ansatz works and used two different form factor behaviours…
The role of the relativistic amplitudes for a number of ${\cal O}(k)$ processes usually neglected in potential model calculations of NN--bremsstrahlung is investigated. In particular, we consider the $\Delta$--excitation pole contributions…
We discuss a possibility to observe fast secondary electrons ($\delta-$electrons) during nuclear $\beta^{-}$-decay in few-electron atoms and ions. Formulas for the corresponding probabilities and explicit expression for the energy spectrum…
We propose formulas of the nuclear beta-decay rate that are useful in a practical calculation. The decay rate is determined by the product of the lepton and hadron current densities. A widely used formula relies upon the fact that the…
The lower and upper bounds on the neutrinoless double beta (0nu-2beta) decay rate are obtained, as functions of the parameters of neutrino oscillations and of the lightest neutrino mass. The constraints on these parameters from the search…
We review the potential to probe new physics with neutrinoless double beta decay $(A,Z) \to (A,Z+2) + 2 e^-$. Both the standard long-range light neutrino mechanism as well as short-range mechanisms mediated by heavy particles are discussed.…
The $\eta \to \pi^0 \gamma \gamma$ decay was investigated by the SND detector at VEPP-2M $e^+e^-$ collider in the reaction $e^+e^-\to\phi\to \eta\gamma$. Here we present the results and some details of this study. We report an upper limit…
The Dalitz distribution and the effective mass spectrum of the lepton pair produced in the decay $\eta_c\to \gamma \ell^+ \ell^-$, as well as the differential cross sections for the crossed channels $\gamma e^-\to \eta_c e^- $ and $e^+…
Based on $2.7 \times 10^9~\psi(3686)$ decays collected with the BESIII detector, the radiative decay $\psi(3686)\to\gamma2(\pi^{+}\pi^{-})\eta$ is investigated to measure properties of S- and P-wave charmonium states. The branching fraction…
A linear relation for charged-particle emissions is presented starting from the microscopic mechanism of the radioactive decay. It relates the logarithms of the decay half-lives with two variables, called $\chi'$ and $\rho'$, which depend…
We report the first observation of the decay D^+ -> eta' e^+ nu_e in two analyses, which combined provide a branching fraction of B(D+ -> eta' e nu) = (2.16 +/- 0.53 +/- 0.07) x 10^{-4}. We also provide an improved measurement of B(D+ ->…
We study the radiative decays of the $Z_c(3900)^0$ in a hadronic molecule picture, where the $Z_c(3900)$ is treated as a $D \bar{D}^\ast +c.c$ hadronic molecule. The partial widths of $\Gamma(Z_c(3900)^0 \to \gamma \eta_c(2S))$ and…
The secondary $\gamma$ rays emitted following a nuclear reaction are often relatively straightforward to detect experimentally. Despite the large volume of such data, a practical formalism for describing these $\gamma$ rays in terms of…