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Spin dependent fragmentation function at Belle

A. Ogawa·M. Grosse-Perdekamp·R. Seidl·K. Hasuko
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Abstract

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. These chiral-odd fragmentation functions (FF) can for example be the so-called Collins FF or the Interference FF. HERMES 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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A. Ogawa, M. Grosse-Perdekamp, R. Seidl, K. Hasuko. 2006-07-11. Spin dependent fragmentation function at Belle. https://doi.org/10.1142/9789812706706_0157

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