Recent STAR spin results and spin measurements at RHIC

The STAR experiment provides measurements of single- and double-spin asymmetries in longitudinally and transversely polarized p+p collisions at √ s = 200 and 510 GeV to deepen our understanding of the proton spin structure and dynamics of parton interactions over a wide range of collision energy, momentum and rapidity of the various produced probes. Polarized processes with W^± production allow us to study the spin-flavor structure of the proton. Recent results obtained by STAR on the double longitudinal asymmetry, A_LL, of pion and jet production at √ s = 200 and 510 GeV, the single longitudinal, A_L, and transverse, A_N, asymmetry of W^± production at √ s =510 GeV are overviewed. STAR results on azimuthal single transverse asymmetry of pion in p^↑ + (p, Au)- and jet + π^± in p↑ + p collisions are discussed. The proposed Forward Calorimeter System (FCS) and Forward Tracking System (FTS) upgrades at STAR would significantly improve the capabilities of existing detectors for measurements of observables such as asymmetries of pion, jet, Drel–Yan pairs produced at forward rapidities.