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Longitudinal spin transfer to $Λ$ hyperons in semi-inclusive deep inelastic scattering with the CLAS12 spectrometer

M. McEneaney ^6,*, A. Vossen^6,36,†, A. Acar⁴², P. Achenbach³⁶, J. S. Alvarado²⁰, M. Amaryan³⁰, W. R. Armstrong¹, H. Atac³⁵, N. A. Baltzell³⁶ et al. (CLAS Collaboration)

N. A. Baltzell³⁶, L. Barion¹³, M. Bashkanov⁴², M. Battaglieri¹⁵, F. Benmokhtar⁷, A. Bianconi^39,19, A. S. Biselli⁸, M. Bondi^16,18, F. Bossù³, S. Boiarinov³⁶, K.-Th. Brinkmann³¹, W. J. Briscoe¹¹, V. D. Burkert³⁶, T. Cao³⁶, R. Capobianco⁵, D. S. Carman³⁶, J. C. Carvajal¹⁰, A. Celentano¹⁵, P. Chatagnon^3,20, V. Chesnokov³³, H. Chinchay²⁶, G. Ciullo^13,9, P. L. Cole²³, M. Contalbrigo¹³, A. D’Angelo^16,32, N. Dashyan⁴⁴, R. De Vita^15,‡, M. Defurne³, S. Diehl^31,5, C. Dilks³⁶, C. Djalali²⁹, R. Dupre²⁰, H. Egiyan³⁶, M. Ehrhart^1,20,§, A. El Alaoui³⁸, L. El Fassi²⁵, M. Farooq²⁶, S. Fegan⁴², R. F. Ferguson⁴¹, I. P. Fernando⁴³, A. Filippi¹⁷, C. Fogler³⁰, K. Gates⁴², G. Gavalian³⁶, D. I. Glazier⁴¹, R. W. Gothe³⁴, Y. Gotra³⁶, B. Gualtieri¹⁰, K. Hafidi¹, H. Hakobyan³⁸, M. Hattawy³⁰, T. B. Hayward²⁴, D. Heddle^4,36, A. Hobart²⁰, M. Holtrop²⁶, Y. Ilieva³⁴, D. G. Ireland⁴¹, H. S. Jo²², S. Joosten^1,35, T. Kageya³⁶, A. Kim⁵, V. Klimenko¹, A. Kripko³¹, V. Kubarovsky³⁶, L. Lanza^16,32, S. Lee¹, P. Lenisa^13,9, D. Marchand²⁰, V. Mascagna^39,19, D. Matamoros²⁰, B. McKinnon⁴¹, T. Mineeva^37,38, M. Mirazita¹⁴, V. Mokeev³⁶, C. Munoz Camacho²⁰, P. Nadel-Turonski^34,36, T. Nagorna¹⁵, K. Neupane³⁴, S. Niccolai²⁰, G. Niculescu²¹, M. Osipenko¹⁵, M. Ouillon²⁵, P. Pandey²⁴, M. Paolone^27,35, L. L. Pappalardo^13,9, R. Paremuzyan^36,26, E. Pasyuk³⁶, S. J. Paul⁴⁰, W. Phelps^4,11, N. Pilleux¹, S. Polcher Rafael³, L. Polizzi¹³, J. Poudel³⁶, Y. Prok³⁰, A. Radic³⁸, T. Reed¹⁰, J. Richards⁵, M. Ripani¹⁵, P. Rossi^36,14, A. A. Rusova³³, C. Salgado^4,28, S. Schadmand¹², A. Schmidt^11,24, M. B. C. Scott^1,∥, E. V. Shirokov³³, S. Shrestha³⁵, E. Sidoretti¹⁶, D. Sokhan⁴¹, N. Sparveris³⁵, M. Spreafico¹⁵, I. Strakovsky¹¹, S. Strauch³⁴, J. A. Tan²², R. Tyson³⁶, M. Ungaro³⁶, P. S. H. Vaishnavi¹³, S. Vallarino¹⁵, C. Velasquez⁴², L. Venturelli^39,19, H. Voskanyan⁴⁴, E. Voutier²⁰, D. P. Watts⁴², Y. Wang²⁴, U. Weerasinghe²⁵, X. Wei³⁶, N. Wickramaarachchi⁶, M. H. Wood², L. Xu²⁰, Z. Xu¹, N. Zachariou⁴², Z. W. Zhao⁶, V. Ziegler³⁶, and M. Zurek¹ (CLAS Collaboration)

¹Argonne National Laboratory, Argonne, Illinois 60439, USA
²Canisius University, Buffalo, New York, USA
³IRFU, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France
⁴Christopher Newport University, Newport News, Virginia 23606, USA
⁵University of Connecticut, Storrs, Connecticut 06269, USA
⁶Duke University, Durham, North Carolina 27708-0305, USA
⁷Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA
⁸Fairfield University, Fairfield, Connecticut 06824, USA
⁹Università di Ferrara, 44121 Ferrara, Italy
¹⁰Florida International University, Miami, Florida 33199, USA
¹¹The George Washington University, Washington, DC 20052, USA
¹²GSI Helmholtzzentrum fur Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
¹³INFN, Sezione di Ferrara, 44100 Ferrara, Italy
¹⁴INFN, Laboratori Nazionali di Frascati, 00044 Frascati, Italy
¹⁵INFN, Sezione di Genova, 16146 Genova, Italy
¹⁶INFN, Sezione di Roma Tor Vergata, 00133 Rome, Italy
¹⁷INFN, Sezione di Torino, 10125 Torino, Italy
¹⁸INFN, Sezione di Catania, 95123 Catania, Italy
¹⁹INFN, Sezione di Pavia, 27100 Pavia, Italy
²⁰Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
²¹James Madison University, Harrisonburg, Virginia 22807
²²Kyungpook National University, Daegu 41566, Republic of Korea
²³Lamar University, 4400MLK Blvd, PO Box 10046, Beaumont, Texas 77710, USA
²⁴Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA
²⁵Mississippi State University, Mississippi State, Mississippi 39762-5167, USA
²⁶University of New Hampshire, Durham, New Hampshire 03824-3568, USA
²⁷New Mexico State University, PO Box 30001, Las Cruces, New Mexico 88003, USA
²⁸Norfolk State University, Norfolk, Virginia 23504, USA
²⁹Ohio University, Athens, Ohio 45701, USA
³⁰Old Dominion University, Norfolk, Virginia 23529, USA
³¹II Physikalisches Institut der Universitaet Giessen, 35392 Giessen, Germany
³²Universita’ di Roma Tor Vergata, 00133 Rome Italy
³³Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, 119234 Moscow, Russia
³⁴University of South Carolina, Columbia, South Carolina 29208, USA
³⁵Temple University, Philadelphia, Pennsylvania 19122, USA
³⁶Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
³⁷Universidad de La Serena, Avda. Juan Cisternas 1200, La Serena, Chile
³⁸Universidad Técnica Federico Santa María, Casilla 110-V Valparaíso, Chile
³⁹Università degli Studi di Brescia, 25123 Brescia, Italy
⁴⁰University of California Riverside, 900 University Avenue, Riverside, California 92521, USA
⁴¹University of Glasgow, Glasgow G12 8QQ, United Kingdom
⁴²University of York, York YO10 5DD, United Kingdom
⁴³University of Virginia, Charlottesville, Virginia 22901, USA
⁴⁴Yerevan Physics Institute, 375036 Yerevan, Armenia

^*Contact author: matthew.mceneaney@duke.edu
^†Contact author: anselm.vossen@duke.edu
^‡Present address: Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA.
^§Present address: DOTA, ONERA, Université Paris-Saclay, 91120, Palaiseau, France.
^∥Present address: The George Washington University, Washington, DC 20052, USA.

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Phys. Rev. D 113, 092019 – Published 29 May, 2026

DOI: https://doi.org/10.1103/d6g9-96xr

Abstract

The polarization of $Λ$ hyperons is preserved in the angular distribution of their decay products. This property allows one to study the spin structure of the $Λ$ . In semi-inclusive deep inelastic scattering where a high energy lepton interacts with a nucleon target and one or more hadrons and the scattered lepton are detected in the final state, the probability for a struck quark to impart the polarization of the lepton to the $Λ$ may be measured. In particular, in electron-proton scattering this quantity may be related to the longitudinal light quark polarization of the $Λ$ . Currently, limited experimental data cannot discriminate between different models of $Λ$ spin structure. This work reports on the measurement of the longitudinal spin transfer $D_{L L^{'}}^{Λ}$ to the $Λ$ using data taken by the CLAS12 spectrometer at Jefferson Lab with a 10.6 GeV longitudinally polarized electron beam and an unpolarized hydrogen target. This measurement is the most precise to date, and, in comparison with theory predictions, it offers valuable insight into the relative dominance of current and target fragmentation in $Λ$ production.

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References (43)

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Phys. Rev. D 113, 092019– Published 29 May, 2026

Vol. 113, Iss. 9 — 1 May 2026

Received 9 September 2025
Accepted 3 April 2026

DOI: https://doi.org/10.1103/d6g9-96xr

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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Longitudinal spin transfer to $Λ$ hyperons in semi-inclusive deep inelastic scattering with the CLAS12 spectrometer

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Longitudinal spin transfer to Λ hyperons in semi-inclusive deep inelastic scattering with the CLAS12 spectrometer

Abstract

Physics Subject Headings (PhySH)

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References (43)

Longitudinal spin transfer to $Λ$ hyperons in semi-inclusive deep inelastic scattering with the CLAS12 spectrometer