This contribution reports on a proof‐of‐principle measurement of the longitudinal spin transfer DLL in inclusive Λ and Λ̄ production in polarized proton‐proton collisions at a center of mass energy . The data sample consists of about 3 × 106 minimum bias events collected in the year 2005 by the STAR experiment at RHIC with proton beam polarizations of up to 50%. The Λ(Λ̄) candidates are reconstructed at mid‐rapidity (|η| < 1) using the STAR Time Projection Chamber via the dominant decay channel Λ → pπ− (Λ̄ → p̄π+). Their mean transverse momentum pT is about 1.3 GeV/c and longitudinal momentum fraction xF = 7.5 × 10−3. The longitudinal Λ(Λ̄) polarization is determined using a method in which the detector acceptance mostly cancels.
Skip Nav Destination
Research Article| June 13 2007
Longitudinal Spin Transfer in Inclusive Λ and Λ̄ Production in Polarized Proton‐proton Collisions at
AIP Conf. Proc. 915, 428–431 (2007)
Qinghua Xu, STAR collaboration; Longitudinal Spin Transfer in Inclusive Λ and Λ̄ Production in Polarized Proton‐proton Collisions at . AIP Conf. Proc. 13 June 2007; 915 (1): 428–431. https://doi.org/10.1063/1.2750813
Download citation file: