Physics Letters B (Oct 2023)

Transverse-spin-dependent azimuthal asymmetries of pion and kaon pairs produced in muon-proton and muon-deuteron semi-inclusive deep inelastic scattering

  • G.D. Alexeev,
  • M.G. Alexeev,
  • C. Alice,
  • A. Amoroso,
  • V. Andrieux,
  • V. Anosov,
  • K. Augsten,
  • W. Augustyniak,
  • C.D.R. Azevedo,
  • B. Badelek,
  • J. Barth,
  • R. Beck,
  • Y. Bedfer,
  • J. Bernhard,
  • M. Bodlak,
  • F. Bradamante,
  • C. Braun,
  • A. Bressan,
  • V.E. Burtsev,
  • W.-C. Chang,
  • C. Chatterjee,
  • M. Chiosso,
  • A.G. Chumakov,
  • S.-U. Chung,
  • A. Cicuttin,
  • P.M.M. Correia,
  • M.L. Crespo,
  • D. D'Ago,
  • S. Dalla Torre,
  • S.S. Dasgupta,
  • S. Dasgupta,
  • F. Del Carro,
  • I. Denisenko,
  • O.Yu. Denisov,
  • S.V. Donskov,
  • N. Doshita,
  • Ch. Dreisbach,
  • W. Dünnweber,
  • R.R. Dusaev,
  • D. Ecker,
  • A. Efremov,
  • C. Elia,
  • D. Eremeev,
  • P. Faccioli,
  • M. Faessler,
  • M. Finger,
  • M. Finger, jr.,
  • H. Fischer,
  • K.J. Flöthner,
  • W. Florian,
  • J.M. Friedrich,
  • V. Frolov,
  • L.G. Garcia Ordòñez,
  • F. Gautheron,
  • O.P. Gavrichtchouk,
  • S. Gerassimov,
  • J. Giarra,
  • D. Giordano,
  • M. Gorzellik,
  • A. Grasso,
  • A. Gridin,
  • M. Grosse Perdekamp,
  • B. Grube,
  • M. Grüner,
  • A. Guskov,
  • D. von Harrach,
  • M. Hoffmann,
  • N. Horikawa,
  • N. d'Hose,
  • C.-Y. Hsieh,
  • S. Huber,
  • S. Ishimoto,
  • A. Ivanov,
  • T. Iwata,
  • M. Jandek,
  • V. Jary,
  • R. Joosten,
  • E. Kabuß,
  • F. Kaspar,
  • A. Kerbizi,
  • B. Ketzer,
  • A. Khatun,
  • G.V. Khaustov,
  • F. Klein,
  • J.H. Koivuniemi,
  • V.N. Kolosov,
  • K. Kondo Horikawa,
  • I. Konorov,
  • V.F. Konstantinov,
  • A.M. Korzenev,
  • A.M. Kotzinian,
  • O.M. Kouznetsov,
  • A. Koval,
  • Z. Kral,
  • F. Krinner,
  • F. Kunne,
  • K. Kurek,
  • R.P. Kurjata,
  • A. Kveton,
  • K. Lavickova,
  • S. Levorato,
  • Y.-S. Lian,
  • J. Lichtenstadt,
  • P.-J. Lin,
  • R. Longo,
  • V.E. Lyubovitskij,
  • A. Maggiora,
  • A. Magnon,
  • N. Makins,
  • N. Makke,
  • G.K. Mallot,
  • A. Maltsev,
  • S.A. Mamon,
  • A. Martin,
  • J. Marzec,
  • J. Matoušek,
  • T. Matsuda,
  • G. Mattson,
  • C. Menezes Pires,
  • F. Metzger,
  • M. Meyer,
  • W. Meyer,
  • Yu.V. Mikhailov,
  • M. Mikhasenko,
  • E. Mitrofanov,
  • D. Miura,
  • Y. Miyachi,
  • R. Molina,
  • A. Moretti,
  • A. Nagaytsev,
  • D. Neyret,
  • M. Niemiec,
  • J. Nový,
  • W.-D. Nowak,
  • G. Nukazuka,
  • A.G. Olshevsky,
  • M. Ostrick,
  • D. Panzieri,
  • B. Parsamyan,
  • S. Paul,
  • H. Pekeler,
  • J.-C. Peng,
  • G. Pesaro,
  • M. Pešek,
  • D.V. Peshekhonov,
  • M. Pešková,
  • S. Platchkov,
  • J. Pochodzalla,
  • V.A. Polyakov,
  • M. Quaresma,
  • C. Quintans,
  • G. Reicherz,
  • C. Riedl,
  • D.I. Ryabchikov,
  • A. Rychter,
  • A. Rymbekova,
  • V.D. Samoylenko,
  • A. Sandacz,
  • S. Sarkar,
  • I.A. Savin,
  • G. Sbrizzai,
  • P. Schiavon,
  • H. Schmieden,
  • A. Selyunin,
  • K. Sharko,
  • L. Sinha,
  • M. Slunecka,
  • F. Sozzi,
  • D. Spülbeck,
  • A. Srnka,
  • M. Stolarski,
  • O. Subrt,
  • M. Sulc,
  • H. Suzuki,
  • S. Tessaro,
  • F. Tessarotto,
  • A. Thiel,
  • J. Tomsa,
  • F. Tosello,
  • A. Townsend,
  • T. Triloki,
  • V. Tskhay,
  • B. Valinoti,
  • B.M. Veit,
  • J.F.C.A. Veloso,
  • B. Ventura,
  • M. Virius,
  • M. Wagner,
  • S. Wallner,
  • K. Zaremba,
  • M. Zavertyaev,
  • M. Zemko,
  • E. Zemlyanichkina,
  • M. Ziembicki

Journal volume & issue
Vol. 845
p. 138155

Abstract

Read online

A set of measurements of azimuthal asymmetries in the production of pairs of identified hadrons in deep-inelastic scattering of muons on transversely polarised 6LiD (deuteron) and NH3 (proton) targets is presented. All available data collected in the years 2003–2004 and 2007/2010 with the COMPASS spectrometer using a muon beam of 160GeV/c at the CERN SPS were analysed. The asymmetries provide access to the transversity distribution functions via a fragmentation function that in principle may be independently obtained from e+e− annihilation data. Results are presented, discussed and compared to existing measurements as well as to model predictions. Asymmetries of π+π− pairs measured with the proton target as a function of the Bjorken scaling variable are sizeable in the range x>0.032, indicating non-vanishing transversity distribution and di-hadron interference fragmentation functions. As already pointed out by several authors, the small asymmetries of π+π− measured on the 6LiD target can be interpreted as indication for a cancellation of u and d-quark transversity distributions.

Keywords