Aula B34 (Laboratori Nazionali di Frascati, Via E. Fermi 40, Frascati)
Laboratori Nazionali di Frascati, Via E. Fermi 40, Frascati
In recent years parton distributions, describing longitudinal momentum, helicity and transversity distributions of quarks and gluons, have been generalized to account also for transverse degrees of freedom. Two new sets of more general distributions, Transverse Momentum Dependent (TMD) parton distributions and Generalized Parton Distributions (GPDs) were introduced to describe transverse momentum and space distributions of partons. Great progress has been made since then in measurements of different Single Spin Asymmetries (SSAs) in semi-inclusive and hard exclusive processes providing access to TMDs and GPDs respectively. Different facilities world-wide including HERMES at HERA, CLAS and Hall-A at JLab and COMPASS at CERN have measurements of TMDs and GPDs as one of their main focuses of research.
Kaon identification provides important additional information about the sea structure in general and spin-orbit correlations in particular. Recent measurements of SSAs at HERMES with charged Kaons indicate that current understanding of the nuclear structure in terms of partonic degrees of freedom is incomplete and more data is needed to resolve the so called “Kaon puzzle”.
Studies of GPDs and TMDs are also one of the main driving forces of the JLab 12 GeV upgrade project. In this talk we present a possible upgrade of the CLAS12 detector at JLab to make Kaon identification available over the full momentum range and the new physics accessible with the CLAS12-RICH detector.