Related papers: Weak $\eta$ production off the nucleon
The CLEO Collaboration recently reported the observation of the $B^0\to D^{*-}p\bar{n}$ mode at a rate only a factor of 4--5 lower than $B^0\to D^{*-}\rho^+$ and $D^{*-}\pi^+$. We try to understand this with a factorization approach of…
New high-precision total and differential cross sections for $\eta$ and $\eta'$ photoproduction on the proton obtained by the A2 Collaboration at the Mainz Microtron are presented. The data for $\eta$ photoproduction demonstrate a cusp at…
The nucleon form factors in free space are usually thought to be modified when a nucleon is bound in a nucleus or immersed in a nuclear medium. We investigate effects of the density-dependent axial and weak-vector form factors on the…
Weak $B^-\rightarrow D^0, \pi^0$ and $D^-\rightarrow {K}^0, \pi^0$ transition form factors are described in both the space- and time-like momentum transfer regions, within a constituent-quark model. Neutrino-meson scattering and…
We study the axial-vector and the induced pseudoscalar form factors associated with the weak transitions between the octet baryon members in nuclear medium, using a covariant constituent quark model. We extend previous calculations of the…
The article contains new results for spin-3/2 and -1/2 resonances. It specializes to the second resonance region, which includes the $P_{11}(1440)$, $D_{13}(1520)$ and $S_{11}(1535)$ resonances. New data on electroproduction enable us to…
Understanding single pion production reactions on free nucleons is the first step towards a correct description of these processes in nuclei, which are important for signal and background contributions in current and near future accelerator…
The physics potential of an intense source of low-energy muons is studied. Such a source is a necessary stage towards building the neutrino factories and muon colliders which are being considered at present. The CERN Neutrino Factory could…
The total cross section for the near threshold eta production in proton-proton collisions has been investigated with the assumption that the production mechanism is due to the emission of a meson x (pi, eta, sigma) from one of the nucleons…
Baryon to meson transition distribution amplitudes (TDAs), non-diagonal matrix elements of the nonlocal three quark operator between a nucleon and a meson state, extend the concept of generalized parton distributions. These non-perturbative…
This report summarizes our study of Neutral Current (NC)-induced photon production in MiniBooNE, as motivated by the low energy excess in this experiment [A. A. Aquilar-Arevalo et al. (MiniBooNE Collaboration), Phys. Rev. Lett. 98, 231801…
The quasielastic production cross sections and polarizations of the hyperons induced by ${\bar\nu}_\mu$ on the free nucleon as well as from $^{40}$Ar in the sub-GeV energy region has been reviewed [1-5]. The effects of the second class…
We have calculated the transition form factors for the electromagnetic excitation of the negative parity resonances of the nucleon using different models previously proposed and we discuss their results and limits by comparison with…
It has been proposed that a sterile neutrino \nu_h with m_h \approx 50 MeV and a dominant decay mode (\nu_h -> \nu\gamma) may be the origin of the experimental anomaly observed at LSND. We define a particular model that could also explain…
In this work, we study the charged-current (anti)neutrino-induced associated particle($K\Lambda$) production($\Delta S=0$) from free nucleons in the energy region of a few GeV, relevant to the (anti)neutrino oscillation experiments with…
Charged and neutral current low energy neutrino cross section predictions from a variety of Monte Carlo generators in present use are compared against existing experimental data. Comparisons are made to experimental data on quasi-elastic,…
We investigate the pseudoscalar transition form factors of nucleon for quasi-elastic scattering and \Delta resonance production in tau-neutrino nucleon scattering via the charged current interactions. Although the pseudoscalar form factors…
Precise neutrino-nucleon amplitudes are essential ingredients for predicting neutrino event rates in current and upcoming long-baseline neutrino oscillation experiments. A common neutrino interaction with a low reaction threshold and with…
The unitary isobar model MAID2007 has been used to analyze the recent data of pion electroproduction. The model contains all four-star resonances in the region below W=2 GeV and both single-Q^2 and Q^2 dependent transition form factors…
The production of the light vector mesons $V = \rho, \omega, \phi$ in the reactions $\pi N \to V N$ and $N N \to V N N$ near threshold is studied. The subsequent electromagnetic decay $V \to \gamma^* \to e^+ e^-$ is particularly suited for…