Related papers: Pion-Muon Asymmetry Revisited
Recent theoretical claims not withstanding, muons can and do oscillate. Muons produced in association with neutrinos (if masses and mixing angles are nonzero) exhibit a joint oscillating spatial distribution. The possible use of muon…
The relative immunity of muons to synchrotron radiation suggests that they might be used in place of electrons as probes in fundamental high-energy physics experiments. Muons are commonly produced indirectly through pion decay by…
Using a self-consistent delta-hole model the pion propagation in isospin asymmetric nuclear matter is studied. In neutron-rich matter, corresponding to heavy nuclei, a significant difference in positive and negative pion light-cone…
We develop a theory of the EPR-like effects due to neutrino oscillations in the $\pi \to \mu\nu$ decays. Its experimental implications are space-time correlations of neutrino and muon when they are both detected, while the pion decay point…
Accelerator-based experiments reliant on charged pion and kaon decays to produce muon-neutrino beams also deliver an associated powerful flux of muons. Therefore, these experiments can additionally be sensitive to light new particles that…
Three recent experiments, which looked at pionic effects in nuclei have concluded that there are no excess pions. This puts into serious question the conventional meson-exchange picture of the nucleon-nucleon interaction. Based on arguments…
The production of positive pions and neutrons by cosmic muons at underground sites of various depths is investigated. We first test the equivalent photon method in the particular case of $\Delta$ excitation by the muon. We find that this…
Differential cross sections for elastic scattering of 21.5 MeV positive and negative pions by Si, Ca, Ni and Zr have been measured as part of a study of the pion-nucleus potential across threshold. The `anomalous' repulsion in the s-wave…
A single-spin asymmetry in the azimuthal distribution of neutral pions relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off longitudinally polarized protons. The…
In this paper we consider the coherence properties of neutrinos produced by the decays of pions in conventional neutrino beams. Using a multi-particle density matrix formalism we derive the oscillation probability for neutrinos emitted by a…
The present anomaly in muon anaomalous magnetic moment can be explained by the presence of a muon-philic $X$ boson which could be a scalar particle or a vector particle with mass less than twice the mass of muon. The muon-philic $X$ boson…
The consequences of a recently introduced irreducible pionic effect in low energy nucleon-deuteron scattering are analyzed. Differential cross-sections, nucleon (vector) and deuteron (vector and tensor) analyzing powers, and four different…
The nuclear symmetry energy as a function of density is rather poorly constrained theoretically and experimentally both below saturation density, but particularly at high density, where very few relevant experimental data exist. We discuss…
Azimuthal asymmetry of vector-meson production in single-transversely polarized proton-proton collisions ($p\up p$) is calculated in the string model of particle production. The asymmetry is generated only during fragmentation of a…
In this work, the self energies of $\pi^0$ and $\pi^{\pm}$ up to one loop order have been calculated in the limit of weak external magnetic field. The effective masses are explicitly dependent on the magnetic field which are modified…
A measurement of the beam-spin asymmetry in the azimuthal distribution of pions produced in semi-inclusive deep-inelastic scattering off protons is presented. The measurement was performed using the {HERMES} spectrometer with a hydrogen gas…
In this work, dispersion relations of $\pi^0$ and $\pi^{\pm}$ have been studied in vacuum in the limit of weak external magnetic field using a phenomenological pion-nucleon $(\pi N)$ Lagrangian. For our purpose, we have calculated the…
The study of pion production in nuclei is important for signal and background determinations in current and future neutrino oscillation experiments. The first step, however, is to understand the pion production reactions at the free nucleon…
A longitudinal double spin asymmetry for \pi^0 production has been measured by the PHENIX collaboration. The asymmetry is sensitive to the polarized gluon distribution and is indicated to be positive by theoretical predictions. We study a…
A single-spin asymmetry in the distribution of exclusively produced pi^+ mesons azimuthally around the virtual photon direction relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of…