학술논문
Transverse extension of partons in the proton probed in the sea-quark range by measuring the DVCS cross section
Document Type
article
Author
R. Akhunzyanov; M.G. Alexeev; G.D. Alexeev; A. Amoroso; V. Andrieux; N.V. Anfimov; V. Anosov; A. Antoshkin; K. Augsten; W. Augustyniak; A. Austregesilo; C.D.R. Azevedo; B. Badełek; F. Balestra; M. Ball; J. Barth; R. Beck; Y. Bedfer; J. Bernhard; K. Bicker; E.R. Bielert; R. Birsa; M. Bodlak; P. Bordalo; F. Bradamante; A. Bressan; M. Büchele; E. Burtin; V.E. Burtsev; W.-C. Chang; C. Chatterjee; M. Chiosso; I. Choi; A.G. Chumakov; S.-U. Chung; A. Cicuttin; M.L. Crespo; S. Dalla Torre; S.S. Dasgupta; S. Dasgupta; O.Yu. Denisov; L. Dhara; S.V. Donskov; N. Doshita; Ch. Dreisbach; W. Dünnweber; R.R. Dusaev; M. Dziewiecki; A. Efremov; P.D. Eversheim; M. Faessler; A. Ferrero; M. Finger; M. Finger, jr.; H. Fischer; C. Franco; N. du Fresne von Hohenesche; J.M. Friedrich; V. Frolov; E. Fuchey; F. Gautheron; O.P. Gavrichtchouk; S. Gerassimov; J. Giarra; I. Gnesi; M. Gorzellik; A. Grasso; A. Gridin; M. Grosse Perdekamp; B. Grube; T. Grussenmeyer; A. Guskov; D. Hahne; G. Hamar; D. von Harrach; R. Heitz; F. Herrmann; N. Horikawa; N. d'Hose; C.-Y. Hsieh; S. Huber; S. Ishimoto; A. Ivanov; Yu. Ivanshin; T. Iwata; V. Jary; R. Joosten; P. Jörg; K. Juraskova; E. Kabuß; A. Kerbizi; B. Ketzer; G.V. Khaustov; Yu.A. Khokhlov; Yu. Kisselev; F. Klein; J.H. Koivuniemi; V.N. Kolosov; K. Kondo; I. Konorov; V.F. Konstantinov; A.M. Kotzinian; O.M. Kouznetsov; Z. Kral; M. Krämer; F. Krinner; Z.V. Kroumchtein; Y. Kulinich; F. Kunne; K. Kurek; R.P. Kurjata; I.I. Kuznetsov; A. Kveton; A.A. Lednev; E.A. Levchenko; M. Levillain; S. Levorato; Y.-S. Lian; J. Lichtenstadt; R. Longo; V.E. Lyubovitskij; A. Maggiora; A. Magnon; N. Makins; N. Makke; G.K. Mallot; S.A. Mamon; B. Marianski; A. Martin; J. Marzec; J. Matoušek; H. Matsuda; T. Matsuda; G.V. Meshcheryakov; M. Meyer; W. Meyer; Yu.V. Mikhailov; M. Mikhasenko; E. Mitrofanov; N. Mitrofanov; Y. Miyachi; A. Moretti; A. Nagaytsev; F. Nerling; D. Neyret; J. Nový; W.-D. Nowak; G. Nukazuka; A.S. Nunes; A.G. Olshevsky; I. Orlov; M. Ostrick; D. Panzieri; B. Parsamyan; S. Paul; J.-C. Peng; F. Pereira; M. Pešek; M. Pešková; D.V. Peshekhonov; N. Pierre; S. Platchkov; J. Pochodzalla; V.A. Polyakov; J. Pretz; M. Quaresma; C. Quintans; S. Ramos; C. Regali; G. Reicherz; C. Riedl; N.S. Rogacheva; D.I. Ryabchikov; A. Rybnikov; A. Rychter; R. Salac; V.D. Samoylenko; A. Sandacz; C. Santos; S. Sarkar; I.A. Savin; T. Sawada; G. Sbrizzai; P. Schiavon; H. Schmieden; K. Schönning; E. Seder; A. Selyunin; L. Silva; L. Sinha; S. Sirtl; M. Slunecka; J. Smolik; A. Srnka; D. Steffen; M. Stolarski; O. Subrt; M. Sulc; H. Suzuki; A. Szabelski; T. Szameitat; P. Sznajder; M. Tasevsky; S. Tessaro; F. Tessarotto; A. Thiel; J. Tomsa; F. Tosello; V. Tskhay; S. Uhl; B.I. Vasilishin; A. Vauth; B.M. Veit; J. Veloso; A. Vidon; M. Virius; S. Wallner; M. Wilfert; J. ter Wolbeek; K. Zaremba; P. Zavada; M. Zavertyaev; E. Zemlyanichkina; N. Zhuravlev; M. Ziembicki
Source
Physics Letters B, Vol 793, Iss , Pp 188-194 (2019)
Subject
Language
English
ISSN
0370-2693
Abstract
We report on the first measurement of exclusive single-photon muoproduction on the proton by COMPASS using 160GeV/c polarised μ+ and μ− beams of the CERN SPS impinging on a liquid hydrogen target. We determine the dependence of the average of the measured μ+ and μ− cross sections for deeply virtual Compton scattering on the squared four-momentum transfer t from the initial to the final proton. The slope B of the t-dependence is fitted with a single exponential function, which yields B=(4.3±0.6stat|sys−0.3+0.1)(GeV/c)−2. This result can be converted into a transverse extension of partons in the proton, 〈r⊥2〉=(0.58±0.04stat|sys−0.02+0.01±0.04model)fm. For this measurement, the average virtuality of the photon mediating the interaction is 〈Q2〉=1.8(GeV/c)2 and the average value of the Bjorken variable is 〈xBj〉=0.056. Keywords: Quantum chromodynamics, Deep inelastic scattering, Exclusive reactions, Deeply virtual Compton scattering, Generalized Parton Distributions, Proton size, COMPASS