First measurement of interference fragmentation on a transversely polarized hydrogen target

Abstract

The HERMES experiment has measured for the first time single target-spin asymmetries in semi-inclusive two-pion production using a transversely polarized hydrogen target. These asymmetries are related to the product of two unknowns, the transversity distribution function and the interference fragmentation function. In the invariant mass range 0.51 GeV < M_inv < 0.97 GeV the measured asymmetry deviates significantly from zero, indicating that two-pion semi-inclusive deep-inelastic scattering can be used to probe transversity.

6 pages, 6 figures, contribution to the proceedings of the International Workshop on Transverse Polarisation Phenomena in Hard Processes (Transversity 2005), Como, Italy, Sep 7 - 10, 2005