ar X iv : h ep - e x / 06 07 01 4 v 1 1 1 Ju l 2 00 6 Spin dependent fragmentation functions at Belle
نویسندگان
چکیده
The measurement of the so far unknown chiral-odd quark transverse spin distribution in either semi-inclusive DIS (SIDIS) or inclusive measurements in pp collisions at RHIC has an additional chiral-odd fragmentation function appearing in the cross section. This chiral-odd fragmentation functions (FF) can for example be the so-called Collins FF [1] or the Interference FF. HERMES [2] has given a first hint that these FFs are nonzero, however in order to measure the transversity one needs these FFs to be precisely known. We have used 29.0 fb −1 of data collected by the Belle experiment at the KEKB e + e − collider to measure azimuthal asymmetries for different charge combinations of pion pairs and thus access the Collins FF.
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ar X iv : h ep - p h / 06 12 08 7 v 1 7 D ec 2 00 6 Collins Effect from Polarized SIDIS and e + e − Data
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