Article
Astronomy & Astrophysics
A. Fatima, M. Sajjad Athar, S. K. Singh
Summary: The study analyzes the production of eta mesons induced by charged current (anti)neutrinos through nonresonant and resonant diagrams using effective Lagrangians. A microscopic model based on SU(3) chiral Lagrangians is employed to determine the contribution from the nonresonant background terms while an effective phenomenological Lagrangian, with parameters obtained from experimental values, is used for the resonant diagrams. The model successfully reproduces experimental data for eta meson production, and predicts numerical values for various distributions and cross sections in the energy range up to 2 GeV. The results show that the S11(1535) resonance dominates the production of eta mesons induced by photons, electrons, neutrinos, and antineutrinos. The findings are relevant for current and future accelerator experiments as well as atmospheric neutrino experiments.
Article
Physics, Multidisciplinary
G. Christiaens, M. Defurne, D. Sokhan, P. Achenbach, Z. Akbar, M. J. Amaryan, H. Atac, H. Avakian, C. Ayerbe Gayoso, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, W. A. Booth, F. Bossu, S. Boiarinov, K. -Th. Brinkmann, W. J. Briscoe, S. Bueltmann, D. Bulumulla, V. D. Burkert, T. Cao, D. S. Carman, J. C. Carvajal, A. Celentano, P. Chatagnon, V. Chesnokov, T. Chetry, G. Ciullo, G. Clash, P. L. Cole, M. Contalbrigo, G. Costantini, A. D'Angelo, N. Dashyan, R. De Vita, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, M. Ehrhart, A. El Alaoui, L. El Fassi, L. Elouadrhiri, S. Fegan, A. Filippi, K. Gates, G. Gavalian, Y. Ghandilyan, G. P. Gilfoyle, F. X. Girod, D. I. Glazier, A. A. Golubenko, G. Gosta, R. W. Gothe, Y. Gotra, K. A. Griffioen, M. Guidal, K. Hafidi, H. Hakobyan, M. Hattawy, F. Hauenstein, T. B. Hayward, D. Heddle, A. Hobart, D. E. Holmberg, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. S. Jo, D. Keller, M. Khachatryan, A. Khanal, W. Kim, A. Kripko, V. Kubarovsky, S. E. Kuhn, V. Lagerquist, L. Lanza, M. L. Kabir, M. Leali, S. Lee, P. Lenisa, X. Li, K. Livingston, I. J. D. MacGregor, D. Marchand, V. Mascagna, G. Matousek, B. McKinnon, C. McLauchlin, Z. E. Meziani, S. Migliorati, R. G. Milner, T. Mineeva, M. Mirazita, V. Mokeev, E. Molina, C. Munoz Camacho, P. Nadel-Turonski, P. Naidoo, K. Neupane, S. Niccolai, M. Nicol, G. Niculescu, M. Osipenko, M. Ouillon, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, S. J. Paul, W. Phelps, N. Pilleux, M. Pokhrel, J. Poudel, J. W. Price, Y. Prok, A. Radic, N. Ramasubramanian, B. A. Raue, Trevor Reed, J. Richards, M. Ripani, J. Ritman, P. Rossi, F. Sabatie, C. Salgado, S. Schadmand, A. Schmidt, M. B. C. Scott, Y. G. Sharabian, E. Shirokov, U. Shrestha, P. Simmerling, N. Sparveris, M. Spreafico, S. Stepanyan, I. I. Strakovsky, S. Strauch, J. A. Tan, N. Trotta, M. Turisini, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, H. Voskanyan, E. Voutier, D. P. Watts, X. Wei, R. Williams, R. Wishart, M. H. Wood, N. Zachariou, J. Zhang, Z. W. Zhao, V. Ziegler, M. Zurek
Summary: We present the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer, with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. Our results significantly expand the Q2 and Bjorken-x phase space beyond existing data in the valence region, providing 1600 new data points with unprecedented statistical uncertainty. These findings set new, tight constraints for future phenomenological studies.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Nuclear
Y. Liang, V Tvaskis, M. E. Christy, A. Ahmidouch, C. S. Armstrong, J. Arrington, R. Asaturyan, S. Avery, O. K. Baker, D. H. Beck, H. P. Blok, C. W. Bochna, W. Boeglin, P. Bosted, M. Bouwhuis, H. Breuer, D. S. Brown, A. Bruell, R. D. Carlini, J. Cha, N. S. Chant, A. Cochran, L. Cole, S. Danagoulian, D. B. Day, J. Dunne, D. Dutta, R. Ent, H. C. Fenker, B. Fox, L. Gan, H. Gao, K. Garrow, D. Gaskell, A. Gasparian, D. F. Geesaman, R. Gilman, P. L. J. Gueye, M. Harvey, R. J. Holt, X. Jiang, M. Jones, C. E. Keppel, E. Kinney, W. Lorenzon, A. Lung, D. J. Mack, P. Markowitz, J. W. Martin, K. McIlhany, D. McKee, D. Meekins, M. A. Miller, R. G. Milner, J. H. Mitchell, H. Mkrtchyan, B. A. Mueller, A. Nathan, G. Niculescu, I Niculescu, T. G. O'Neill, V Papavassiliou, S. F. Pate, R. B. Piercey, D. Potterveld, R. D. Ransome, J. Reinhold, E. Rollinde, O. Rondon, P. Roos, A. J. Sarty, R. Sawafta, E. C. Schulte, E. Segbefia, C. Smith, S. Stepanyan, S. Strauch, V Tadevosyan, L. Tang, R. Tieulent, A. Uzzle, W. F. Vulcan, S. A. Wood, F. Xiong, L. Yuan, M. Zeier, B. Zihlmann, V Ziskin
Summary: This article reports on a detailed study of longitudinal strength in the nucleon resonance region, with new experimental results. The study used inclusive electron-proton cross section data measured at Jefferson Lab Hall C to accurately perform longitudinal/transverse separations and determine the values of the longitudinal component and inelastic structure functions. The study found significant magnitude and defined mass peaks in the resonance longitudinal component, and observed quark-hadron duality in the separated structure functions above Q(2) = 1 GeV2.
Article
Astronomy & Astrophysics
Ya-Ping Xie, V. P. Goncalves
Summary: The study focuses on the investigation of timelike Compton scattering (TCS) in ultraperipheral pPb collisions at the LHC, aiming to probe the generalized parton distributions (GPDs) and understand the 3-dimensional description of quark and gluon content of hadrons. The TCS process involves exclusive dilepton production through the subprocess gamma p -> gamma* p -> l+l- p, with a real photon emitted by the nucleus. The paper provides estimations of the TCS differential cross section and the interference between the TCS and Bethe-Heitler (BH) amplitudes, as well as predictions for the TCS, BH, and interference contributions in the kinematical range covered by the LHC detectors.
Article
Astronomy & Astrophysics
Izabela Babiarz, Victor P. Goncalves, Wolfgang Schaefer, Antoni Szczurek
Summary: In this letter, the exclusive ηc production by γ*γ interactions in eA collisions is studied, and it is demonstrated that future experimental analysis of this process can improve the description of the ηctransition form factor. The distributions of rapidity, transverse momentum, and photon virtuality are estimated, considering the expected energy and target configurations at the EIC, EicC, and LHeC, as well as different predictions for the light-front wave function of the ηc meson. The results suggest that electron-ion colliders can provide supplementary data to those obtained in e-e+ colliders.
Article
Astronomy & Astrophysics
Jun-Zhang Wang, Xiang Liu, Takayuki Matsuki
Summary: Recent measurements by the LHCb collaboration reveal a potential contribution from the Pc(4380)+ state in the process of Bs -> J=psi pp over bar, providing possible evidence for the existence of the pentaquark Pc(4380).
Article
Physics, Nuclear
G. Chanfray, M. Ericson
Summary: The study evaluates the cross section for gamma production by neutrinos through a meson exchange effect, resulting in a slight increase in the cross section, especially at low neutrino energies, which may impact the understanding of the low-energy excess of electron-like events observed in the MiniBooNE experiment.
Article
Physics, Particles & Fields
Ya-Ping Xie, V. P. Goncalves
Summary: The exclusive dilepton photoproduction in pp and pAu collisions at RHIC is studied, taking into account the contributions of the Bethe-Heitler (BH) and the timelike Compton scattering (TCS) processes. The TCS amplitude is estimated at next-to-leading-order of the strong running coupling constant and assuming the Goloskokov-Kroll model for the quark and gluon generalized parton distributions. The TCS differential cross section and the interference between the TCS and BH amplitudes are predicted in the kinematical range covered by the RHIC detectors.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Particles & Fields
U. Egede, T. Hadavizadeh, M. Singla, P. Skands, M. Vesterinen
Summary: This paper studies the role of multi-parton interactions in the production of doubly-heavy hadrons using simulation samples and comparisons with different generators. New methods of speeding up simulations and experimental measurement suggestions are proposed.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
Hadi Hashamipour, Muhammad Goharipour, K. Azizi, S. V. Goloskokov
Summary: In this study, a comprehensive analysis of various experimental data, including nucleon electromagnetic form factors, nucleon charge and magnetic radii, proton axial form factors, and wide-angle Compton scattering cross sections, is conducted to determine the generalized parton distributions (GPDs) at zero skewness, xi=0. Three types of GPDs, namely Hq, SIM;Hq, and Eq, are simultaneously determined, taking into account the contributions of sea quarks. The results reveal significant tensions between the wide-angle Compton scattering and proton magnetic form factor data, especially at larger values of -t. However, when sea quark contributions are considered and both wide-angle Compton scattering and proton magnetic form factor data are included in the analyses simultaneously, the extracted GPDs show relatively good agreement with the light-cone QCD sum rules and lattice QCD predictions.
Article
Astronomy & Astrophysics
Adrian Dumitru, Heikki Mantysaari, Risto Paatelainen
Summary: In this study, the three point correlation function of color charge densities for a proton on the light cone is evaluated explicitly in light -one gauge, including both C-conjugation even and odd contributions. Perturbative corrections to the three-quark light -cone wave function due to the emission of an internal gluon are taken into account, with verification of the Ward identity and cancellation of UV divergences in the sum of all diagrams to ensure the correlator is independent of the renormalization scale.
Article
Physics, Nuclear
M. Mai, M. Doering, C. Granados, H. Haberzettl, Ulf-G Meissner, D. Roenchen, I Strakovsky, R. Workman
Summary: The study analyzes pion electroproduction off the proton in a new framework based on a general parametrization of transition amplitudes, incorporating constraints from gauge invariance and threshold behavior. Large-scale fits were performed, resulting in a set of solutions with chi(2)(dof) = 1.69-1.81, allowing for the assessment of the systematic uncertainty of the approach.
Article
Astronomy & Astrophysics
Adrian Dumitru, Heikki Maentysaari, Risto Paatelainen
Summary: This paper investigates the issue of the imaginary part of the nonforward eikonal scattering matrix for dipole-proton scattering at high energy, which is caused by a C-odd three-gluon exchange. Numerical estimates are presented for the perturbative odderon amplitude, considering the dipole size, impact parameter, relative azimuthal angle, and light-cone momentum cutoff x. The proton is approximated as yrqqqjqqqi thorn yrqqqgjqqqgi, where yrqqq represents a nonperturbative three-quark model wave function, and gluon emission is computed using light-cone perturbation theory. It is found that the odderon amplitude increases as x decreases from 0.1 to 0.01, and a reversal of this energy dependence is expected at even lower x, indicating the onset of universal small-x renormalization evolution.
Article
Astronomy & Astrophysics
Marat Siddikov, Ivan Schmidt
Summary: In this paper, we analyze the exclusive photoproduction of heavy quarkonia pairs in the collinear factorization framework. The amplitude of the J/psi - eta c quarkonia pair process is evaluated in the leading order of the strong coupling alpha s and expressed in terms of gluon generalized parton distributions (GPDs) in the proton. Numerical estimates in the kinematics of the Electron Ion Collider show that the cross section of the process is sufficiently large for experimental studies in the photoproduction regime.
Article
Astronomy & Astrophysics
Yu Jia, Zhewan Mo, Jichen Pan, Jia-Yue Zhang
Summary: In this study, the photoproduction of various C-even heavy quarkonia, such as eta(c(b)) and chi(c(b)J) with J = 0, 1, 2, is investigated via one-photon exchange channel in ep collision. The results show that the photoproduction rates of eta(c) through this mechanism are comparable to that through the Odderon-initiated mechanism, even in the Regge limit. Future measurements in EIC and EicC are crucial to determine the dominant mechanism.
