Bonn 2010 – wissenschaftliches Programm
HK 16.3: Vortrag
Dienstag, 16. März 2010, 15:00–15:15, HG III
The Transverse Single Spin Asymmetry AN in Inclusive Hadron Production lp↑→ hX at HERMES — •Florian Sanftl — Institut für theoretische Physik, Universität Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
The azimuthal single-spin asymmetry (SSA) AN in inclusive hadron production of charged pions and kaons on a transversely polarised hydrogen target at the HERMES experiment at DESY is presented. Due to the inclusive character of the analysis the final asymmtries are evaluated dependent on the transverse hadron momentum Ph⊥ and xF. For positively charged hadrons asymmetries with a maxium value of AN∼ 6% were found. The asymmetries for negatively charged hadrons are consistent with zero. The evaluation of the Ph⊥-dependence of the asymmetries allows to give an estimate for higher-twist contributions to the mechanisms causing sizeable asymmetries AN. The two main mechanisms giving rise to a non-zero SSA AN are the Sivers- and the Collins-effect.
This work has been supported by the German Bundesministerium für Bildung und Forschung (BMBF) and the Japanese Society for the Promotion of Science (JSPS).