2018/12/27 by Qinghua Xu, Xu, Qing-Hua
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High-Energy Particle Collisions Research #Nuclear Experiment (nucl-ex) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.1812.10621
openalex publication_date 2018/12/27 · openalex created_date 2019/01/11 · openalex updated_date 2026/07/28
The longitudinal or transverse spin transfer to Lambda and anti-Lambda hyperons in polarized proton-proton collisions is expected to be sensitive to the helicity or transversity distributions of strange and anti-strange quarks of the proton, and to the corresponding polarized fragmentation function. We report the first measurement of the transverse spin transfer to Λ and Λ along the polarization direction of the fragmenting quark, DTT, in transversely polarized proton-proton collisions at 200 GeV with the STAR experiment at RHIC. The data correspond to an integrated luminosity of 18 pb-1, and cover a kinematic range of |η|< 1.2 and transverse momentum pT up to 8 GeV/c. We also report an improved measurement of the longitudinal spin transfer DLL to Λ and Λ with pT up to 6 GeV/c, using data with about twelve times larger figure-of-merit than the previously published STAR results. The prospects of hyperon polarization measurements in the forward pseudo-rapidity region (2.5