Measurement of transverse Λ and Λ¯ hyperon polarization in pPb collisions at √^SNN = 5.02 TeV

The transverse polarization of Λ and (Formula Presented) hyperons is measured in pPb collisions collected by the LHCb experiment at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The polarization is averaged over hyperon transverse momentum in the range 0.15 < p _T < 6.00 GeV=c, and Feynman-x in the ranges 0.005 < x _F < 0.040 (forward region) and −0.10 < x _F < −0.01 (backward region) defined relative to the proton beam direction. The transverse polarization is found to be compatible with zero for both Λ and Λ̄ hyperons. The results are also measured as a function of p _T and x _F with no significant dependence on these variables observed. The results are compared with previous experimental measurements at different center-of-mass energies and collision environments.