Abstract
We report the observation of transverse polarization-dependent azimuthal correlations in charged pion pair production with the STAR experiment in collisions at RHIC. These correlations directly probe quark transversity distributions. We measure signals in excess of 5 standard deviations at high transverse momenta, at high pseudorapidities , and for pair masses around the mass of the meson. This is the first direct transversity measurement in collisions.
- Received 2 April 2015
DOI:https://doi.org/10.1103/PhysRevLett.115.242501
© 2015 American Physical Society