CERN Accelerating science

Preprint
Report number	arXiv:0902.0184
Title	Transverse Spin Physics at COMPASS
Author(s)	Sozzi, Federica (Trieste U. ; INFN, Trieste)
Publication	2009
Collaboration	for the COMPASS Collaboration
Imprint	03 Feb 2009
Number of pages	4
Note	Comments: 4 pages, 2 figures, proceedings of 16th International Workshop on Deep Inelastic Scattering and Related Subjects (DIS 2008), London, England, 7-11 Apr 2008 4 pages, 2 figures, proceedings of 16th International Workshop on Deep Inelastic Scattering and Related Subjects (DIS 2008), London, England, 7-11 Apr 2008
Presented at	16th International Workshop on Deep Inelastic Scattering and Related Subjects, London, UK, 7 - 11 Apr 2008
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN SPS ; COMPASS NA58
Abstract	The study of transverse spin effects is part of the scientific program of COMPASS, a fixed target experiment at the CERN SPS. COMPASS investigates the transversity PDFs in semi-inclusive DIS, using a longitudinally polarized muon beam of 160 GeV/c impinging on a transversely polarized target. From 2002 to 2004, data have been collected using a $^6$LiD target transversely polarized. Transversity has been measured using different quark polarimeters: the azimuthal distribution of single hadrons, the azimuthal dependence of the plane containing hadron pairs, and the measurement of the transverse polarization of baryons ($\Lambda$ hyperons). All the asymmetries have been found to be small, and compatible with zero, a result which has been interpreted as a cancellation between the u and d-quark contributions. In 2007 COMPASS has taken data using a NH$_3$ polarized proton target which will give complementary information on transverse spin effects.
Other source	Inspire
Copyright/License	preprint: (License: arXiv nonexclusive-distrib 1.0)