Azimuthal asymmetries for hadron distributions inside a jet in hadronic collisions

Journal Article · Tue Feb 01 00:00:00 EST 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.83.034021· OSTI ID:21504881

D'Alesio, Umberto; Pisano, Cristian ^[1]; Murgia, Francesco ^[2]

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1. Dipartimento di Fisica, Universita di Cagliari, Cittadella Universitaria, I-09042 Monserrato (Italy)
2. Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari, C. P. 170, I-09042 Monserrato (Italy)

Using a generalized parton model approach including spin and intrinsic parton motion effects, and assuming the validity of factorization for large-p{sub T} jet production in hadronic collisions, we study the azimuthal distribution around the jet axis of leading unpolarized or (pseudo)scalar hadrons, namely pions, produced in the jet fragmentation process. We identify the observable leading-twist azimuthal asymmetries for the unpolarized and single-polarized case related to quark and gluon-originated jets. We account for all physically allowed combinations of the transverse momentum-dependent (TMD) parton distribution and fragmentation functions, with special attention to the Sivers, Boer-Mulders, and transversity quark distributions, and to the Collins fragmentation function for quarks (and to the analogous functions for gluons). For each of these effects we evaluate, at central and forward rapidities and for kinematical configurations accessible at BNL-RHIC, the corresponding potentially maximized asymmetry (for {pi}{sup +} production), obtained by saturating natural positivity bounds (and the Soffer bound for transversity) for the distribution and fragmentation functions involved and summing additively all partonic contributions. We then estimate, for both neutral and charged pions, the asymmetries involving TMD functions for which parametrizations are available. We also study the role of the different mechanisms, and the corresponding transverse single-spin asymmetries, for large-p{sub T} inclusive-jet production.

• OSTI ID: 21504881
• Journal Information: Physical Review. D, Particles Fields, Vol. 83, Issue 3; Other Information: DOI: 10.1103/PhysRevD.83.034021; (c) 2011 American Institute of Physics; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
BNL
BROOKHAVEN RHIC
COLLISIONS
CONFIGURATION
DISTRIBUTION
FACTORIZATION
FRAGMENTATION
GLUONS
PARTICLE RAPIDITY
PIONS PLUS
QUARKS
SPIN
TRANSVERSE MOMENTUM
ACCELERATORS
ANGULAR MOMENTUM
BOSONS
ELEMENTARY PARTICLES
FERMIONS
HADRONS
HEAVY ION ACCELERATORS
LINEAR MOMENTUM
MESONS
NATIONAL ORGANIZATIONS
PARTICLE PROPERTIES
PIONS
PSEUDOSCALAR MESONS
STORAGE RINGS
US AEC
US DOE
US ERDA
US ORGANIZATIONS