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Baryon–antibaryon photoproduction cross sections off the proton

F. Afzal ³, M. Albrecht ²⁷, M. Amaryan ²⁴, S. Arrigo³³, V. Arroyave⁹, A. Asaturyan ²⁷, A. Austregesilo ²⁷, Z. Baldwin ⁴, F. Barbosa²⁷ et al. (GlueX Collaboration)

F. Barbosa²⁷, J. Barlow ^10,26, E. Barriga ¹⁰, R. Barsotti¹⁶, D. Barton ²⁴, V. Baturin²⁴, V. V. Berdnikov ²⁷, A. Berger ¹³, W. Boeglin ⁹, M. Boer³¹, W. J. Briscoe ¹¹, T. Britton²⁷, R. Brunner ¹⁰, S. Cao¹⁰, C. Chen⁶, E. Chudakov ²⁷, G. Chung ³¹, P. L. Cole ¹⁸, O. Cortes¹¹, V. Crede ¹⁰, M. M. Dalton ²⁷, D. Darulis ¹³, A. Deur ²⁷, L. Dietrich³, S. Dobbs ¹⁰, A. Dolgolenko ¹⁷, M. Dugger ¹, R. Dzhygadlo¹⁴, D. Ebersole ¹⁰, M. Edo⁷, H. Egiyan ²⁷, P. Eugenio ¹⁰, A. Fabrizi¹⁹, C. Fanelli ³³, S. Fang ¹⁵, M. Fritsch³, S. Furletov ²⁷, L. Gan ²³, H. Gao⁸, A. Gardner¹, A. Gasparian²², D. I. Glazier ¹³, C. Gleason ³⁰, B. Grube ²⁷, J. Guo ⁴, J. Hernandez ¹⁰, K. Hernandez¹, N. Herrmann³, N. D. Hoffman ⁴, D. Hornidge ²¹, G. M. Huber ²⁵, P. Hurck ¹³, W. Imoehl ⁴, D. G. Ireland ¹³, M. M. Ito ¹⁰, I. Jaegle ²⁷, N. S. Jarvis ⁴, T. Jeske²⁷, M. Jing¹⁵, R. T. Jones ⁷, V. Kakoyan³⁵, G. Kalicy⁵, X. Kang⁶, V. Khachatryan¹⁶, C. Kourkoumelis ², A. LaDuke ⁴, I. Larin²⁷, D. Lawrence ²⁷, D. I. Lersch ²⁷, H. Li ^4,33,*, B. Liu ¹⁵, K. Livingston ¹³, L. Lorenti³³, V. Lyubovitskij ^29,28, H. Marukyan ³⁵, V. Matveev ¹⁷, M. McCaughan ²⁷, M. McCracken ^4,32, C. A. Meyer ⁴, R. Miskimen ¹⁹, R. E. Mitchell ¹⁶, P. Moran³³, L. Ng ²⁷, E. Nissen ²⁷, S. Orešić²⁵, A. I. Ostrovidov ¹⁰, Z. Papandreou ²⁵, L. Pentchev ²⁷, K. J. Peters¹⁴, L. Puthiya Veetil²³, S. Rakshit ¹⁰, J. Reinhold ⁹, A. Remington ¹⁰, J. Ritman ^14,3, G. Rodriguez ¹⁰, K. Saldana ¹⁶, S. Schadmand ¹⁴, A. M. Schertz ¹⁶, K. Scheuer ³³, A. Schmidt ¹¹, R. A. Schumacher ^4,†, J. Schwiening ¹⁴, M. Scott¹¹, N. Septian ¹⁰, P. Sharp ¹¹, V. J. Shen ³, X. Shen ¹⁵, M. R. Shepherd ¹⁶, J. Sikes¹⁶, H. Singh²⁵, A. Smith ²⁷, E. S. Smith ³³, A. Somov²⁷, S. Somov²⁰, J. R. Stevens ³³, I. I. Strakovsky ¹¹, B. Sumner¹, K. Suresh ³³, V. V. Tarasov ¹⁷, S. Taylor ²⁷, A. Teymurazyan²⁵, A. Thiel ¹², M. Thomson²⁵, T. Viducic ²⁴, T. Whitlatch²⁷, Y. Wunderlich ⁷, B. Yu ⁸, J. Zarling ²⁵, Z. Zhang ³⁴, X. Zhou ³⁴, and B. Zihlmann ²⁷ (GlueX Collaboration)

¹Polytechnic Sciences and Mathematics, School of Applied Sciences and Arts, Arizona State University, Tempe, Arizona 85287, USA
²Department of Physics, National and Kapodistrian University of Athens, 15771 Athens, Greece
³Ruhr-Universität-Bochum, Institut für Experimentalphysik, D-44801 Bochum, Germany
⁴Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
⁵Department of Physics, The Catholic University of America, Washington, D.C. 20064, USA
⁶School of Mathematics and Physics, China University of Geosciences, Wuhan 430074, People's Republic of China
⁷Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
⁸Department of Physics, Duke University, Durham, North Carolina 27708, USA
⁹Department of Physics, Florida International University, Miami, Florida 33199, USA
¹⁰Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
¹¹Department of Physics, The George Washington University, Washington, D.C. 20052, USA
¹²Physikalisches Institut, Justus-Liebig-Universität Gießen, D-35390 Gießen, Germany
¹³School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
¹⁴GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
¹⁵Institute of High Energy Physics, Beijing 100049, People's Republic of China
¹⁶Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
¹⁷National Research Centre Kurchatov Institute, Moscow 123182, Russia
¹⁸Department of Physics, Lamar University, Beaumont, Texas 77710, USA
¹⁹Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA
²⁰National Research Nuclear University Moscow Engineering Physics Institute, Moscow 115409, Russia
²¹Department of Physics, Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
²²Department of Physics, North Carolina A&T State University, Greensboro, North Carolina 27411, USA
²³Department of Physics and Physical Oceanography, University of North Carolina at Wilmington, Wilmington, North Carolina 28403, USA
²⁴Department of Physics, Old Dominion University, Norfolk, Virginia 23529, USA
²⁵Department of Physics, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
²⁶Department of Mathematics, Physics, and Computer Science, Springfield College, Springfield, Massachusetts, 01109, USA
²⁷Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
²⁸Laboratory of Particle Physics, Tomsk Polytechnic University, 634050 Tomsk, Russia
²⁹Department of Physics, Tomsk State University, 634050 Tomsk, Russia
³⁰Department of Physics and Astronomy, Union College, Schenectady, New York 12308, USA
³¹Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
³²Department of Physics, Washington & Jefferson College, Washington, Pennsylvania 15301, USA
³³Department of Physics, William & Mary, Williamsburg, Virginia 23185, USA
³⁴School of Physics and Technology, Wuhan University, Wuhan, Hubei 430072, People's Republic of China
³⁵A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), 0036 Yerevan, Armenia

^*Contact author: haoli@wm.edu
^†Contact author: schumacher@cmu.edu

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Phys. Rev. C 113, 045207 – Published 13 April, 2026

DOI: https://doi.org/10.1103/h197-l9dw

Abstract

The GlueX experiment at Jefferson Lab has observed $p \bar{p}$ and, for the first time, $Λ \bar{Λ}$ and $p \bar{Λ}$ photoproduction from a proton target at photon energies up to 11.6 GeV. The angular distributions are forward peaked for all produced pairs, consistent with Regge-like $t$ -channel exchange. Asymmetric wide-angle antibaryon distributions show the presence of additional processes. In a phenomenological model, we find consistency with a double- $t$ -channel exchange process where antibaryons are created only at the middle vertex. The model matches all observed distributions with a small number of free parameters. In the hyperon channels, we observe a clear distinction between photoproduction of the $Λ \bar{Λ}$ and $p \bar{Λ}$ systems but general similarity to the $p \bar{p}$ system. We report both total cross sections and cross sections differential with respect to momentum transfer and the invariant masses of the created particle pairs. No narrow resonant structures were found in these reaction channels. The suppression of $s \bar{s}$ quark pairs relative to $d \bar{d}$ quark pairs is similar to what has been seen in other reactions.

Physics Subject Headings (PhySH)

Corrections

30 April, 2026

Correction: The affiliation assigned to author V. J. Shen was incorrect and has been fixed.

Article Text

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Phys. Rev. C 113, 045207– Published 13 April, 2026

Vol. 113, Iss. 4 — April 2026

Received 5 November 2025
Revised 27 January 2026
Accepted 24 February 2026
Corrected 30 April 2026

DOI: https://doi.org/10.1103/h197-l9dw

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP³.

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Baryon–antibaryon photoproduction cross sections off the proton

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