Probing quark-gluon interactions with transverse polarized scattering.
نویسندگان
چکیده
We have extracted QCD matrix elements from our data on doubly polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element d˜2, which arises strictly from quark-gluon interactions, to be unambiguously nonzero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer.
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ورودعنوان ژورنال:
- Physical review letters
دوره 105 10 شماره
صفحات -
تاریخ انتشار 2010