Test of QCD and a measurement of Λ from scaling violations in the proton structure function F2( x, Q2) at high Q2

Abstract

Scaling violations in the proton structure function F 2( x, Q 2) measured with high statistics in deep inelastic scattering of muons on a hydrogen target are compared to predictions of perturbative QCD. Excellent agreement is observed with numerical solutions of the evolution equations in leading and next-to-leading order. The QCD mass scale parameter Λ is determined from these data both in a flavour nonsinglet approximation and with a complete flavour singlet and nonsinglet treatment. An estimate of the gluon distribution in the proton is given.