Beam Spin Asymmetry in Semi-Inclusive Electroproduction of Hadron Pairs

M. Mirazita , H. Avakian , A. Courtoy , S. Pisano , S. Adhikari , M.J. Amaryan , G. Angelini , H. Atac , N.A. Baltzell , L. Barion , M. Battaglieri , I. Bedlinskiy , F. Benmokhtar , A. Bianconi , A.S. Biselli , F. Bossù (1) , S. Boiarinov , W.J. Briscoe , W.K. Brooks , D. Bulumulla , V.D. Burkert , D.S. Carman , J.C. Carvajal , A. Celentano , P. Chatagnon (2) , T. Chetry , G. Ciullo , B. Clary , P.L. Cole , M. Contalbrigo , V. Crede , A. d'Angelo , N. Dashyan , R. de Vita , M. Defurne (1) , A. Deur , S. Diehl , C. Dilks , C. Djalali , R. Dupre (2) , H. Egiyan , M. Ehrhart , A. El Alaoui , L. El Fassi , P. Eugenio , S. Fegan , R. Fersch , A. Filippi , T.A. Forest , Y. Ghandilyan , G. Gavalian , G.P. Gilfoyle , K.L. Giovanetti , F.X. Girod , D.I. Glazier , E. Golovatch , R.W. Gothe , K.A. Griffioen , M. Guidal (2) , L. Guo , K. Hafidi , H. Hakobyan , M. Hattawy , T.B. Hayward , D. Heddle , K. Hicks , A. Hobart (2) , M. Holtrop , Q. Huang (1) , Y. Ilieva , D.G. Ireland , B.S. Ishkhanov , E.L. Isupov , D. Jenkins , H.S. Jo (2) , K. Joo , D. Keller , A. Khanal , M. Khandaker , C.W. Kim , W. Kim , F.J. Klein , V. Kubarovsky , S.E. Kuhn , L. Lanza , M. Leali , P. Lenisa , K. Livingston , I .J .D. Macgregor , D. Marchand (2) , N. Markov , L. Marsicano , V. Mascagna , B. Mckinnon , R.G. Milner , T. Mineeva , V. Mokeev , C. Mullen , C. Munoz Camacho (2) , K. Neupane , G. Niculescu , T. O'Connell , M. Osipenko , M. Paolone , L.L. Pappalardo , R. Paremuzyan , K. Park , E. Pasyuk , W. Phelps , D. Pocanic , O. Pogorelko , J. Poudel , Y. Prok , B.A. Raue , M. Ripani , J. Ritman , A. Rizzo , P. Rossi , F. Sabatié (1) , C. Salgado , A. Schmidt , R.A. Schumacher , Y.G. Sharabian , U. Shrestha , O. Soto , N. Sparveris , S. Stepanyan , I.I. Strakovsky , S. Strauch , N. Tyler , M. Ungaro , L. Venturelli , H. Voskanyan , A. Vossen , E. Voutier (2) , D. Watts , K. Wei , X. Wei , M.H. Wood , B. Yale , N. Zachariou , J. Zhang , Z.W. Zhao

1 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers
2 IJCLab - Laboratoire de Physique des 2 Infinis Irène Joliot-Curie

A first measurement of the longitudinal beam spin asymmetry ALU in the semi-inclusive electroproduction of pairs of charged pions is reported. ALU is a higher-twist observable and offers the cleanest access to the nucleon twist-3 parton distribution function e(x). Data have been collected in the Hall-B at Jefferson Lab by impinging a 5.498-GeV electron beam on a liquid-hydrogen target, and reconstructing the scattered electron and the pion pair with the CLAS detector. One-dimensional projections of the ALUsinϕR moments are extracted for the kinematic variables of interest in the valence quark region. The understanding of dihadron production is essential for the interpretation of observables in single-hadron production in semi-inclusive DIS, and pioneering measurements of single-spin asymmetries in dihadron production open a new avenue in studies of QCD dynamics.

Mots clés: Elementary Particles and Fields; spin: asymmetry: measured; parton: distribution function; deep inelastic scattering: semi-inclusive reaction; hadron: electroproduction; hadron: pair production; pi: pair production; electron: beam; quark: valence; dimension: 1; quantum chromodynamics; Jefferson Lab; polarization: longitudinal; higher-twist; kinematics; nucleon; CLAS; experimental results

Domaines: Physique des Hautes Energies - Expérience [hep-ex]; Physique Nucléaire Expérimentale [nucl-ex]

M. Mirazita, H. Avakian, A. Courtoy, S. Pisano, S. Adhikari, et al.. Beam Spin Asymmetry in Semi-Inclusive Electroproduction of Hadron Pairs. Physical Review Letters, 2021, 126 (6), pp.062002. ⟨10.1103/PhysRevLett.126.062002⟩. ⟨hal-02987481⟩