Measurement of the Parity-Violating Longitudinal Single-Spin Asymmetry for W{sup {+-}} Boson Production in Polarized Proton-Proton Collisions at {radical}(s)=500 GeV

Journal Article · Fri Feb 11 04:00:00 EST 2011 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.106.062002· OSTI ID:21532293

Aggarwal, M M; Bhati, A K; Pruthi, N K ^[1]; Ahammed, Z; Dong, X; Grebenyuk, O; Hjort, E; Jacobs, P; Kikola, D P; Kiryluk, J; Klein, S R; Masui, H; Matis, H S; Naglis, M; Odyniec, G; Olson, D; Ploskon, M A; Poskanzer, A M; Powell, C B; Ritter, H G ^[2]

---

1. Panjab University, Chandigarh 160014 (India)
2. Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

We report the first measurement of the parity-violating single-spin asymmetries for midrapidity decay positrons and electrons from W{sup +} and W{sup -} boson production in longitudinally polarized proton-proton collisions at {radical}(s)=500 GeV by the STAR experiment at RHIC. The measured asymmetries, A{sub L}{sup W+}=-0.27{+-}0.10(stat.){+-}0.02(syst.){+-}0.03(norm.) and A{sub L}{sup W-}=0.14{+-}0.19(stat.){+-}0.02(syst.){+-}0.01(norm.), are consistent with theory predictions, which are large and of opposite sign. These predictions are based on polarized quark and antiquark distribution functions constrained by polarized deep-inelastic scattering measurements.

• OSTI ID: 21532293
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 6 Vol. 106; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACCELERATORS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
ANTIQUARKS
ASYMMETRY
BARYON-BARYON INTERACTIONS
BROOKHAVEN RHIC
COLLISIONS
DEEP INELASTIC SCATTERING
DISTRIBUTION FUNCTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
FUNCTIONS
GEV RANGE
GEV RANGE 100-1000
HADRON-HADRON INTERACTIONS
HEAVY ION ACCELERATORS
INELASTIC SCATTERING
INTERACTIONS
LEPTON-BARYON INTERACTIONS
LEPTON-HADRON INTERACTIONS
LEPTON-NUCLEON INTERACTIONS
LEPTONS
MATTER
NUCLEON-NUCLEON INTERACTIONS
PARITY
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PARTICLE PROPERTIES
POSITRONS
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
QUARKS
SCATTERING
STORAGE RINGS