Are there approximate relations among transverse momentum dependent distribution functions?
نویسندگان
چکیده
منابع مشابه
Bounds on Transverse Momentum Dependent Distribution Functions
Here, P and S denote the parent hadron momentum and spin, and the relevant component of the quark momentum is x = p/P, the light-cone momentum fraction. The components a = a · n∓ stem from vectors n+ and n−, satisfying n2+ = n 2 − = 0 and n+ ·n− = 1, which are fixed by the momentum that introduces the large scaleQ, together with a (soft) hadron momentum. When only the leading part in orders of ...
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In the field theoretical description of hadronic scattering processes, single transverse-spin asymmetries arise due to gluon initial and final state interactions. These interactions lead to process dependent Wilson lines in the operator definitions of transverse momentum dependent parton distribution functions. In particular for hadron–hadron scattering processes with hadronic final states this...
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We use Lorentz invariance and the QCD equations of motion to study the evolution of functions that appear at leading order in a 1/Q expansion in azimuthal asymmetries. This includes the evolution equation of the Collins fragmentation function. The moments of these functions are matrix elements of known twist two and twist three operators. We present the evolution in the large Nc limit, restrict...
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The cross section for semi-inclusive deep inelastic scattering can be decomposed in terms of 18 structure functions. At low transverse momentum of the detected hadron, the structure functions can be expressed in terms of transverse-momentum-dependent parton distribution and fragmentation functions. Here, a few selected examples are illustrated and discussed. PACS: 13.60.-r,13.85.Ni,13.88.+e I p...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2008
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.77.014023