Transverse extension of partons in the proton probed in the sea-quark range by measuring the DVCS cross section

0508853 - ÚPT 2020 RIV NL eng J - Článek v odborném periodiku
Akhunzyanov, R. - Alexeev, M. - Alexeev, G. D. - Srnka, Aleš … celkem 224 autorů
Transverse extension of partons in the proton probed in the sea-quark range by measuring the DVCS cross section.
Physics Letters. B. Roč. 793, JUN (2019), s. 188-194. ISSN 0370-2693. E-ISSN 1873-2445
Institucionální podpora: RVO:68081731
Klíčová slova: quantum chromodynamics * deep inelastic scattering * exclusive reactions * deeply virtual Compton scattering * COMPASS
Obor OECD: Nuclear physics
Impakt faktor: 4.384, rok: 2019
Způsob publikování: Open access
https://reader.elsevier.com/reader/sd/pii/S0370269319302710?token=62B15C6035818A7299FEF7AF9000DC3B8903BBEBDECBF443FA86027D1563BC8552D36B4A19421C8E898A82CE1CE179C9

We report on the first measurement of exclusive single-photon muoproduction on the proton by COMPASS using 160 GeV/c polarised mu(+) and mu(-) beams of the CERN SPS impinging on a liquid hydrogen target. We determine the dependence of the average of the measured mu(+) and mu(-) 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 +/- 0.6(stat) (+0.1)(-0.3)vertical bar(sys)) (GeV/c)(-2). This result can be converted into a transverse extension of partons in the proton,root(r(perpendicular to)(2)) = (0.58 +/- 0.04(stat) (+0.01)(-0.02)vertical bar(sys) +/- 0.04(model)) fm. For this measurement, the average virtuality of the photon mediating the interaction is Q(2) = 1.8 (GeV/c)(2) and the average value of the Bjorken variable is X-Bj = 0.056.
Trvalý link: http://hdl.handle.net/11104/0299652