Česky
English
Výbor pro spolupráci ČR se Spojeným ústavem jaderných výzkumů Přihlášení
Leading-order determination of the gluon polarisation from semi-inclusive deep inelastic scattering data

Autor
Adolph C. Institute of Physics, University of Erlangen Nuremberg
Finger Miroslav, prof. Ing. DrSc. Matematicko-fyzikální fakulta UK v Praze
Finger Michael, M.Sc. CSc. Matematicko-fyzikální fakulta UK v Praze, SÚJV Dubna
Slunečka Miloš, Ing. Matematicko-fyzikální fakulta UK v Praze, SÚJV Dubna
et al.  COMPASS collaboration
Smolík Jan, Mgr. Ph.D. Fakulta jaderná a fyzikálně inženýrská ČVUT
Taševský  Marek, Mgr. Ph.D. Fyzikální ústav AV ČR

Rok
2017

Časopis
European Physical Journal C, 77 (4), 209

Web


Obsah
Using a novel analysis technique, the gluon polarisation in the nucleon is re-evaluated using the longitudinal double-spin asymmetry measured in the cross section of semi-inclusive single-hadron muoproduction with photon virtuality Q(2) > 1 ( GeV/c)(2). The data were obtained by the COMPASS experiment at CERN using a 160 GeV/c polarised muon beam impinging on a polarised (LiD)-Li-6 target. By analysing the full range in hadron transverse momentum p(T), the different pT-dependences of the underlying processes are separated using a neural-network approach. In the absence of pQCD calculations at next-to-leading order in the selected kinematic domain, the gluon polarisation Delta g/g is evaluated at leading order in pQCD at a hard scale of mu(2) = < Q(2) > = 3( GeV/c)(2). It is determined in three intervals of the nucleon momentum fraction carried by gluons, x(g), covering the range 0.04< x(g)< 0.28 and does not exhibit a significant dependence on xg. The average over the three intervals, < Delta g/g > = 0.113 +/- 0.038(stat) +/- 0.036( syst) at < x(g) > approximate to 0.10, suggests that the gluon polarisation is positive in the measured x(g) range.

Příklad citace článku:
C. Adolph, M. Finger, M. Finger, M. Slunečka, . et al., J. Smolík, M. Taševský , "Leading-order determination of the gluon polarisation from semi-inclusive deep inelastic scattering data", European Physical Journal C, 77 (4), 209 (2017)