∆G from Compass
نویسنده
چکیده
Measurements of the gluon polarization ∆G G via the open charm channel and based on the helicity asymmetry of large transverse-momentum hadrons in the final state are presented. The data have been collected in the years 2002-2004 by the COMPASS experiment at CERN using a 160 GeV/c polarized muon beam scattered off a polarized 6LiD target. The new result for ∆G G from the charm channel is −0.57 ± 0.41(stat.) at xG ≃ 0.15 and scale μ2 ≃ 13 (GeV/c)2. The gluon polarization from high-pT hadron pairs is ∆G G = 0.016 ± 0.058(stat.) ± 0.055(syst.) at xG ≃ 0.085 +0.07 −0.035 (Q 2 < 1 (GeV/c)2 and μ2 ≃ 3 (GeV/c)2) 1) address: Andrzej Soltan Institute for Nuclear Studies, Hoza 69,00-681 Warsaw, Poland, [email protected], Work partially supported by SPUB 621/E-78/SPB/CERN/P-03/DWM576/2002-2006.
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