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arXiv · 0712.3178

Transversity signals at COMPASS

By COMPASS Collaboration
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Abstract

COMPASS is a fixed target experiment at the CERN SPS, with a rich physics program focused on nucleon spin structure and on hadron spectroscopy. One of the main goals of the spin program is the measurement of the transverse spin distribution function $Δ_T q(x)$ in semi-inclusive DIS off transversely polarized nucleons. For this purpose approximately 20% of the running time in the years 2002 to 2004 with the longitudinally polarized muon beam of 160 GeV and with $^6$LiD polarized target was used to collect data with the target polarized transversely with respect to the beam direction. The 2002 data have been already analysed and published. We present here the preliminary results from the full statistics for the Collins and Sivers single hadron asymmetries and for the transverse spin asymmetry in hadron pair production.

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By COMPASS Collaboration. 2007-12-19. Transversity signals at COMPASS. https://doi.org/10.1016/j.nuclphysbps.2007.08.088

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