The curvature of F p 2 ( x , Q 2 ) as a probe of the range of validity of perturbative QCD evolutions in the small - x region
نویسنده
چکیده
Perturbative NLO and NNLO QCD evolutions of parton distributions are studied, in particular in the (very) small-x region, where they are in very good agreement with all recent precision measurements of F p 2 (x,Q 2). These predictions turn out to be also rather insensitive to the specific choice of the factorization scheme (MS or DIS). A characteristic feature of perturbative QCD evolutions is a positive curvature of F p 2 which increases as x decreases. This perturbatively stable prediction provides a sensitive test of the range of validity of perturbative QCD.
منابع مشابه
QCD Evolutions in the small–x Region
The curvature of DIS structure functions like F p 2 (x,Q ), i.e., its second derivative with respect to the photon’s virtuality Q at fixed values of x, plays a decisive role in probing the range of validity of perturbative QCD evolutions of parton distributions in the small-x region. This has been observed recently [1, 2, 3, 4] and it was demonstrated that NLO(MS) evolutions imply a positive cu...
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