Direct photon production cross sections obtained in high statistics p̄p and pp collisions at √s = 24.3 GeV at the CERN SPS are used in a next-to-leading order QCD analysis. From the cross section difference σ(p̄p → γX) - σ(pp → γX) and quark distributions measured in deep inelastic scattering, a determination of the strong coupling constant, αS, is performed via a measurement of A(4)MS. This measurement yields a value A(4)MS = 210 ± 22(stat.) ± 44(syst.)+105-36(theo.) MeV. The corresponding value of αS expressed at M2Z is αS(M2Z) = 0.1112 ± 0.0016(stat.) ± 0.0033(syst.)+0.0077-0.0034 (theo.).
|Original language||English (US)|
|Number of pages||6|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|State||Published - 1999|