We calculate the transverse single-spin asymmetry (SSA) for J/ψ production in proton-proton collisions, within non-relativistic QCD, employing the transverse momentum dependent, generalized parton model, which includes both spin and intrinsic motion effects. In particular, we study the role of the color octet mechanism in accessing the gluon Sivers function. In doing that, we also show, within this approach, how the singularities coming from color octet terms in the low-PT region can be handled, leading to finite cross sections. Predictions for both unpolarized cross sections and SSAs are given and compared against PHENIX data. Estimates for LHCb in the fixed target mode are also presented.

Single-spin asymmetries in p↑p → J/ψ+X within a TMD approach: role of the color octet mechanism

D’Alesio, Umberto;Pisano, Cristian;SANGEM, RAJESH
2019

Abstract

We calculate the transverse single-spin asymmetry (SSA) for J/ψ production in proton-proton collisions, within non-relativistic QCD, employing the transverse momentum dependent, generalized parton model, which includes both spin and intrinsic motion effects. In particular, we study the role of the color octet mechanism in accessing the gluon Sivers function. In doing that, we also show, within this approach, how the singularities coming from color octet terms in the low-PT region can be handled, leading to finite cross sections. Predictions for both unpolarized cross sections and SSAs are given and compared against PHENIX data. Estimates for LHCb in the fixed target mode are also presented.
HARD-SCATTERING; DRELL-YAN; PSI
File in questo prodotto:
File Dimensione Formato  
ppjpsi NRQCD DAlesio2019_Article_Single-spinAsymmetriesInPUparr.pdf

accesso aperto

Descrizione: articolo principale
Tipologia: versione editoriale
Dimensione 826.66 kB
Formato Adobe PDF
826.66 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11584/281976
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 12
  • ???jsp.display-item.citation.isi??? 11
social impact