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Related papers: Pion-Muon Asymmetry Revisited

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Azimuthal asymmetry of vector-meson production in single-transversely polarized proton-proton collisions ($p\up p$) is calculated in a model based on the string fragmentation. The string is spanned by a valence quark of the projectile…

High Energy Physics - Phenomenology · Physics 2011-07-19 Jan Czyzewski

Muon decay is self-analyzing: the spectral-angular distribution of the emitted electron reveals the spin orientation of the polarized muon. Here, we show that the same feature applies to muons in non-plane-wave states and helps reveal the…

High Energy Physics - Phenomenology · Physics 2024-10-10 Pengcheng Zhao , Igor P. Ivanov , Pengming Zhang

We calculate the cross section and single-spin azimuthal asymmetry, A_n(t) for inclusive neutron production in pp collisions at forward rapidities relative to the polarized proton. Absorptive corrections to the pion pole generate a relative…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Z. Kopeliovich , I. K. Potashnikova , Ivan Schmidt , J. Soffer

Within the framework of the quantum molecular dynamics transport model, the pion production and constraint of the high-density symmetry energy in heavy-ion collisions near threshold energy have been thoroughly investigated. The energy…

Nuclear Theory · Physics 2024-06-10 Heng-Jin Liu , Ban Zhang , Yuan-Qing Guo , Hui-Gan Cheng , Si-Na Wei , Zhao-Qing Feng

We compute the light-cone momentum distributions of pions in the nucleon in chiral effective theory using both pseudovector and pseudoscalar pion-nucleon couplings. For the pseudovector coupling we identify \delta-function contributions…

High Energy Physics - Phenomenology · Physics 2013-04-03 M. Burkardt , K. S. Hendricks , Chueng-Ryong Ji , W. Melnitchouk , A. W. Thomas

In neutrino-nucleus interactions, a proton produced with a correlated pion might exhibit a left-right asymmetry relative to the lepton scattering plane even when the pion is absorbed. Absent in other proton production mechanisms, such an…

High Energy Physics - Experiment · Physics 2019-10-30 Tejin Cai , Xianguo Lu , Daniel Ruterbories

Experimental measurement of the probability of direct decay of a pion into a positron allows searching for interactions beyond the Standard Model: test of the hypothesis about the universality of the charged current,search for new…

Instrumentation and Detectors · Physics 2020-10-05 Vladimir I. Selivanov

Single-spin asymmetry appears due to the interference of single and double gluon exchange between protons. A heavy fermion model is used to describe the jet production in the interaction of gluon with the proton implying the further…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Ahmedov , E. N. Antonov , E. Bartos , E. A. Kuraev , E. Zemlyanaya

Heavy neutral gauge boson $Z^\prime$ is proposed in many new physics models. It has rich phenomena at the future muon collider. We study the properties of $Z^\prime$ boson with the process of $\mu^+ \mu^- \rightarrow q \bar{q}$, $\mu^+…

High Energy Physics - Phenomenology · Physics 2024-01-01 Zongyang Lu , Honglei Li , Zhi-Long Han , Zong-Guo Si , Liuxin Zhao

It is shown how the single spin asymmetry observed in inclusive pion production is related, in the helicity basis, to the imaginary part of the product of two different distribution amplitudes, rather than to the usual quark and gluon…

High Energy Physics - Phenomenology · Physics 2009-10-28 Mauro Anselmino , M. E. Boglione , F. Murgia

We derive an analytic result for the pion pole contribution to the light-by-light scattering correction to the anomalous magnetic moment of the muon, $a_\mu = (g_\mu-2)/2$. Using the vector meson dominance model (VMD) for the pion…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ian Blokland , Andrzej Czarnecki , Kirill Melnikov

We have searched for the pion decay pi^+ --> mu^+ X, where X is a neutral particle of mass 33.905 MeV. This process was suggested by the KARMEN Collaboration to explain an anomaly in their observed time distribution of neutrino induced…

High Energy Physics - Experiment · Physics 2008-11-26 M. Daum , M. Janousch , P-R. Kettle , J. Koglin , D. Pocanic , J. Schotmueller , C. Wigger , Z. G. Zhao

A positive muon is a spin-1/2 particle. Beams of muons with all their spins polarized can be prepared and subsequently implanted in various types of condensed matter. The subsequent precession and relaxation of their spins can then be used…

Strongly Correlated Electrons · Physics 2014-10-13 S. J. Blundell

We estimate the beam-normal single-spin asymmetry in elastic lepton-proton scattering without employing the ultrarelativistic approximation. Our calculation is relevant for analyses of muon scattering at energies of few hundred MeV and…

High Energy Physics - Phenomenology · Physics 2019-11-28 Oleksandr Koshchii , Andrei Afanasev

The recently reported measurement of the muon's anomalous magnetic moment differs from the standard model prediction by 2.6 standard deviations. We examine the implications of this discrepancy for supersymmetry. Deviations of the reported…

High Energy Physics - Phenomenology · Physics 2009-10-09 Jonathan L. Feng , Konstantin T. Matchev

We study the sensitivity of past and future stopped-pion experiments to light, invisible dark sector particles produced in exotic pion decays. We consider two-body decays involving sterile neutrinos, $\pi^+ \to \ell^+ N$, as well as…

High Energy Physics - Phenomenology · Physics 2026-01-13 Wolfgang Altmannshofer , Jeff A. Dror , Pierce Giffin , Stefania Gori , Ollie Jackson , Khai Luong , Patrick Schwendimann , Se Rang Seo

We perform a stability analysis of the homogeneous ground state of nuclear matter against inhomogeneous perturbations of the pion condensate. In $\beta$-equilibrium, restricting the baryon species to nucleons only, we observe no…

Nuclear Theory · Physics 2026-05-18 Theo F. Motta , Randall H. V. Pradinett , Gastão Krein

The most fundamental to the elementary particles is the mass they posses and it would be of importance to explore a possible relationship amongst their masses. Here, an attempt is made to investigate this important aspect irrespective of…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. N. Shah , T. A. Mir

A set of measurements of azimuthal asymmetries in the production of pairs of identified hadrons in deep-inelastic scattering of muons on transversely polarised $^6$LiD (deuteron) and NH$_3$ (proton) targets is presented. All available data…

High Energy Physics - Experiment · Physics 2023-01-06 The COMPASS Collaboration

Polarization of a vortex state fermion has rich structure due to the nontrivial momentum distribution of wave function. This larger freedom provides an unique opportunity to prepare fermions in exotic polarized states, which do not exist…

High Energy Physics - Phenomenology · Physics 2022-12-28 Pengcheng Zhao