Longitudinal double-spin asymmetry and cross section for inclusive neutral pion production at midrapidity in polarized proton collisions at {radical}(s)=200 GeV

Journal Article · Tue Dec 01 00:00:00 EST 2009 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.80.111108· OSTI ID:21313433

Abelev, B I; Barannikova, O; Betts, R R; Garcia-Solis, E J; Hofman, D J; Hollis, R S; Iordanova, A; Kauder, K; Suarez, M C ^[1]; Aggarwal, M M; Bhati, A K; Kumar, L; Pruthi, N K ^[2]; Ahammed, Z; Chattopadhyay, S; Mazumdar, M R. Dutta; Ganti, M S; Ghosh, P; Mohanty, B; Mondal, M M ^[3]

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1. University of Illinois at Chicago, Chicago, Illinois 60607 (United States)
2. Panjab University, Chandigarh 160014 (India)
3. Variable Energy Cyclotron Centre, Kolkata 700064 (India)

We report a measurement of the longitudinal double-spin asymmetry A{sub LL} and the differential cross section for inclusive {pi}{sup 0} production at midrapidity in polarized proton collisions at {radical}(s)=200 GeV. The cross section was measured over a transverse momentum range of 1<p{sub T}<17 GeV/c and found to be in good agreement with a next-to-leading order perturbative QCD calculation. The longitudinal double-spin asymmetry was measured in the range of 3.7<p{sub T}<11 GeV/c and excludes a maximal positive gluon polarization in the proton. The mean transverse momentum fraction of {pi}{sup 0}'s in their parent jets was found to be around 0.7 for electromagnetically triggered events.

• OSTI ID: 21313433
• Journal Information: Physical Review. D, Particles Fields, Vol. 80, Issue 11; Other Information: DOI: 10.1103/PhysRevD.80.111108; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
COLLISIONS
COMPUTERIZED SIMULATION
DIFFERENTIAL CROSS SECTIONS
GEV RANGE 100-1000
GLUONS
PERTURBATION THEORY
PIONS NEUTRAL
POLARIZATION
POLARIZED BEAMS
PROTON-PROTON INTERACTIONS
PROTONS
QUANTUM CHROMODYNAMICS
SPIN
TRANSVERSE MOMENTUM