Title :
A general experimental overview including SIDIS and DY

Speaker:
Leslie C. Bland

Abstract :
Large transverse single spin asymmetries (SSA) are observed for 
pion production in polarized proton collisions up to the highest collision
energies for which there are polarized beams.  Such spin effects at
lower energies spurred extensions to perturbative QCD that are now
identified as transverse momentum dependence (TMD) for distribution
and fragmentation functions.  The TMD interpretation of transverse SSA
has been widely applied to semi-inclusive deep inelastic scattering.
This contribution will give an experimental overview of transverse SSA
and will discuss prospects for completing a measurement of polarized
Drell Yan production.  Theory predicts a sign change between
transverse SSA in semi-inclusive deep inelastic scattering and
polarized Drell Yan for spin- and transverse-momentum dependent
distribution functions.  This prediction will be tested by experiment
in the near future.