Longitudinal double-spin asymmetry A1p and spin-dependent structure function g1p of the proton at small values of x and Q2

6533b823fe1ef96bd127fdbb

RESEARCH PRODUCT

Longitudinal double-spin asymmetry A1p and spin-dependent structure function g1p of the proton at small values of x and Q2

P.d. Eversheim H. Suzuki C.d.r. Azevedo Jen-chieh Peng V. Andrieux V. Andrieux Adam Szabelski M. Wilfert O.p. Gavrichtchouk Martin Bodlak L. Sinha T. Matsuda E.a. Levchenko M.g. Alexeev S. Uhl J. Giarra Michal Dziewiecki R.p. Kurjata Miroslav Sulc Y.-s. Lian V. Anosov F. Tessarotto M. Grosse Perdekamp F. Giordano Laura Gonzalez Silva Johannes Bernhard Johannes Bernhard Ch. Dreisbach E. M. Kabuß A. Nagaytsev F. Balestra N. Pierre N. Pierre A. Guskov Andres Cicuttin A. Moretti Z.v. Kroumchtein P. Jörg A. Grasso A. Srnka C. Quintans J.f.c.a. Veloso Frank Klein F. Kunne G. D. Alexeev I.a. Savin M. Ziembicki I. Orlov S. Ramos I. Konorov I. Konorov W. Dünnweber K. Königsmann Valery E. Lyubovitskij V.d. Samoylenko Yakov Petrovich Kulinich F. Gautheron W.-d. Nowak K. Schmidt Andrea Ferrero Norihiro Doshita F. H. Heinsius R. Heitz K. Zaremba O.m. Kouznetsov L. Dhara Markus Ball G. Hamar S. Levorato V.e. Burtsev N. Mitrofanov B. Badelek C. Regali Yu. Kisselev G.v. Khaustov R. Salac Nikolay Anfimov N. D'hose O.yu. Denisov Z. Kral Naomi C R Makins V.a. Polyakov A. Maggiora S. Dalla Torre S. Sarkar B. Ketzer A. Rychter M. Ostrick Arseniy Rybnikov A. Vauth J. Smolik G.v. Meshcheryakov G. Sbrizzai R. Longo E.r. Bielert M. Büchele V.n. Kolosov R. Birsa A. Amoroso Yu. V. Mikhailov K. Schönning S. Sirtl O. Subrt O. Subrt M. Finger W. Augustyniak S. V. Donskov M. Pešek R. Joosten N. Du Fresne Von Hohenesche N. Du Fresne Von Hohenesche J. Lichtenstadt R. Beck J.h. Koivuniemi J.h. Koivuniemi Mikhail Mikhasenko T. Iwata E. Fuchey A. Kerbizi A.s. Nunes S.s. Dasgupta M. Quaresma D.v. Peshekhonov D. Panzieri M. Gorzellik L. Capozza K. Kondo F. Pereira Y. Miyachi A.a. Lednev Janusz Marzec E. Seder D.i. Ryabchikov D.i. Ryabchikov K. Bicker K. Bicker M. V. Zavertyaev T. Grussenmeyer M. Pešková Jan Matousek Jan Matousek G. Reicherz Celso Augusto Guimarães Santos Franco Bradamante Y. Bedfer P. Sznajder C. Riedl J. Nový J. Nový D. Neyret Jan Tomsa H. Schmieden C. Chatterjee B. Grube S.-u. Chung J.m. Friedrich A.v. Efremov D. Steffen D. Steffen A. Gridin S. Huber T. Szameitat M. A. Faessler A. Sandacz M. Meyer M. Meyer A.g. Chumakov A. Thiel C. Franco François Herrmann E. Zemlyanichkina M. Krämer P. Schiavon M. Virius P. Kremser S.a. Mamon Ilya Kuznetsov M. Slunecka A. Antoshkin P. Bordalo M. Aghasyan H. Matsuda J. Pochodzalla F. Nerling J. Pretz A. Kveton Kamil Augsten Kamil Augsten S. Dasgupta A. Austregesilo T. Sawada M. Stolarski I. Gnesi M. Chiosso W. Meyer K. Kurek M. Tasevsky E. Mitrofanov Alexandr Selyunin Nour Makke W. C. Chang Andrew Ivanov Alessandro Bressan D. Von Harrach S. Platchkov P. Zavada J. Barth Maria Liz Crespo Gerhard K. Mallot V. Jary T. Weisrock S. Gerassimov S. Gerassimov N. Horikawa F. Tosello S. Tessaro D. Hahne F. Krinner Yu.a. Khokhlov Aram Kotzinian R. Windmolders R.r. Dusaev V. Tskhay B.i. Vasilishin J. Ter Wolbeek G. Nukazuka A. Magnon Anne-laure Martin V.f. Konstantinov S. Wallner S. Ishimoto H. Fischer N.s. Rogacheva A. Vidon B. Marianski Bakur Parsamyan A.g. Olshevsky M. Levillain C.-y. Hsieh V. Frolov V. Frolov Soumen Paul I. J. Choi

subject

Physics Nuclear and High Energy Physics Muon Proton 010308 nuclear & particles physics media_common.quotation_subject Hadron Elementary particle 01 natural sciences Asymmetry Baryon Nuclear physics 0103 physical sciences High Energy Physics::Experiment Nuclear Experiment 010306 general physics Nucleon Lepton media_common

description

Abstract We present a precise measurement of the proton longitudinal double-spin asymmetry A 1 p and the proton spin-dependent structure function g 1 p at photon virtualities 0.006 ( GeV / c ) 2 Q 2 1 ( GeV / c ) 2 in the Bjorken x range of 4 × 10 − 5 x 4 × 10 − 2 . The results are based on data collected by the COMPASS Collaboration at CERN using muon beam energies of 160 GeV and 200 GeV . The statistical precision is more than tenfold better than that of the previous measurement in this region. In the whole range of x , the measured values of A 1 p and g 1 p are found to be positive. It is for the first time that spin effects are found at such low values of x .

year	journal	country	edition	language
2018-06-01	Physics Letters B

https://doi.org/10.1016/j.physletb.2018.03.044