Monte Carlo simulation of events with Drell-Yan lepton pairs from antiproton-proton collisions

Journal Article · Fri Apr 01 04:00:00 EST 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.71.074014· OSTI ID:20708985

Bianconi, A; Radici, Marco ^[1]

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1. Dipartimento di Chimica e Fisica per l'Ingegneria e per i Materiali, Universita di Brescia, I-25123 Brescia (Italy)

The complete knowledge of the nucleon spin structure at leading twist requires also addressing the transverse spin distribution of quarks, or transversity, which is yet unexplored because of its chiral-odd nature. Transversity can be best extracted from single-spin asymmetries in fully polarized Drell-Yan processes with antiprotons, where valence contributions are involved anyway. Alternatively, in single-polarized Drell-Yan the transversity happens convoluted with another chiral-odd function, which is likely to be responsible for the well known (and yet unexplained) violation of the Lam-Tung sum rule in the corresponding unpolarized cross section. We present Monte Carlo simulations for the unpolarized and single-polarized Drell-Yan pp{sup ({up_arrow}}{sup )}{yields}{mu}{sup +}{mu}{sup -}X at different center-of-mass energies in both configurations where the antiproton beam hits a fixed proton target or it collides on another proton beam. The goal is to estimate the minimum number of events needed to extract the above chiral-odd distributions from future measurements at the high energy storage ring (HESR) at GSI. It is important to study the feasibility of such experiments at HESR in order to demonstrate that interesting spin physics can be explored already using unpolarized antiprotons.

• OSTI ID: 20708985
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 7 Vol. 71; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTIPROTON BEAMS
ANTIPROTONS
ASYMMETRY
CHIRAL SYMMETRY
CHIRALITY
COMPUTERIZED SIMULATION
DISTRIBUTION
DRELL MODEL
INCLUSIVE INTERACTIONS
MONTE CARLO METHOD
MUONS MINUS
MUONS PLUS
POLARIZATION
POLARIZED BEAMS
PROTON BEAMS
PROTON-ANTIPROTON INTERACTIONS
PROTON-PROTON INTERACTIONS
QUARKS
SPIN
SUM RULES
VALENCE