Semi-Inclusive DIS with kaons using the CLAS12 experiment.

In the CLAS12 experiment at Jefferson Lab, 12 GeV polarized electrons are scattered off (polarized) nucleons and the final-state particles are efficiently detected over a large solid angle. Precise Semi-Inclusive Deep Inelastic Scattering (SIDIS) studies, characterized by the measurement of at least one generated hadron together with the scattered electron, provide access to new types of Parton Distribution Functions (PDFs) and Fragmentation Functions (FFs) sensitive to specific aspects of the QCD dynamics. CLAS12 data on the single- and double-pion production channel have reached unprecedented statistical precision in the valence region. A Ring Imaging Cherenkov (RICH) detector has been realized to extend the SIDIS studies on the final states with kaons. This work describes the analysis of the Beam Spin Asymmetry in kaon electro-production, $i.e.$, the difference between the number of events measured in opposite states of beam helicity. The study will provide complementary data to the pion case and other experiments and access to the so-called transverse-momentum--dependent PDFs and FFs. The key role of the PID improvement provided by the RICH detector will be also detailed.