Single – spin Asymmetries in Semi – inclusive Pion Produc - tion
نویسنده
چکیده
For the first time single–spin asymmetries in semi–inclusive pion production are measured by the Hermes experiment with a transversely polarised hydrogen target. Two different sine–modulations are extracted which can be related to the transversity δq(x) and Sivers f 1T (x) quark distribution functions. The extracted sine–moments still contain small sub–leading twist contributions which can be extracted from Hermes data combining the results from the transversely polarised hydrogen target with previously measured results from a longitudinally polarised hydrogen target.
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