More on the Burkhardt-Cottingham sum rule in QCD
نویسندگان
چکیده
منابع مشابه
Burkhardt-Cottingham sum rule and forward spin polarizabilities in Heavy Baryon Chiral Perturbation Theory
We study spin-dependent sum rules for forward virtual Compton scattering (VVCS) off the nucleon in heavy baryon chiral perturbation theory (HBChPT) at order O(p4). We show how these sum rules can be evaluated from low energy expansions (in the virtual photon energy) of the forward VVCS amplitude. We study in particular the Burkhardt-Cottingham sum rule in HBChPT and the higher terms in the low ...
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A description of the generalized Gerasimov-Drell-Hearn sum rules for proton, neutron and deuteron is suggested. The proton consideration confirms the earlier conjecture, that the structure function gT features a smooth Q−dependence, while the structure function g2 is changing rapidly, due to the elastic contribution to the Burkhardt-Cottingham sum rule. The neutron case features the close conne...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 1995
ISSN: 0370-2693
DOI: 10.1016/0370-2693(94)01648-v