Polarizations of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi mathvariant="italic">J</mml:mi><mml:mi>/</mml:mi><mml:mi>ψ</mml:mi></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi mathvariant="italic">ψ</mml:mi></mml:mrow><mml:mrow><mml:mo>′</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>in Hadroproduction at the Tevatron in the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display=

Yuan, Feng; Kong, Chao

doi:10.1103/physrevlett.87.022002

Cited by 39 publications

(26 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…56. A similar trend for the polarization as a function of p T is found in some other analyses of the color-singlet channel, such those in the k T factorization approach [639][640][641][642] (see Fig. 55), the gluon-tower approach [680], and the s-channel-QQcut approach [681,682].…”

Section: Quarkonium Polarization: a Key Observablesupporting

confidence: 54%

“…The processes in which the QQ pair is produced by the exchange of two gluons in the t channel [ Fig. 50(f)] were investigated in the k T -factorization approach [639][640][641][642]. This approach is relevant in the high-energy limit s ŝ, where s (ŝ) denotes the square of the total four-momentum of the colliding hadrons (partons).…”

Section: −4mentioning

confidence: 99%

“…In the case of quarkonium production, the k T -factorization approach has usually been applied within the CSM [637][638][639][640][641][642]. In k T -factorization formulas, the parton distributions for the initial-state hadrons depend on the parton transverse momentum, as well as on the parton longitudinal momentum fraction.…”

Section: Kt Factorizationmentioning

confidence: 99%

See 2 more Smart Citations

Heavy quarkonium: progress, puzzles, and opportunities

Brambilla¹,

Eidelman²,

Heltsley³

et al. 2011

Advances in the Physics of Particles and Nuclei

103

View full text Add to dashboard Cite

A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the B-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations at BESIII, the LHC, RHIC, FAIR, the Super Flavor and/or Tau-Charm factories, JLab, the ILC, and beyond. The list of newly-found conventional states expanded to include hc(1P ), χc2(2P ), B + c , and η b (1S). In addition, the unexpected and still-fascinating X(3872) has been joined by * Editors † Section coordinators ‡ Corresponding author: bkh2@cornell.edu more than a dozen other charmonium-and bottomonium-like "XY Z" states that appear to lie outside the quark model. Many of these still need experimental confirmation. The plethora of new states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of cc, bb, and bc bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. Lattice QCD has grown from a tool with computational possibilities to an industrialstrength effort now dependent more on insight and innovation than pure computational power. New effective field theories for the description of quarkonium in different regimes have been developed and brought to a high degree of sophistication, thus enabling precise and solid theoretical predictions. Many expected decays and transitions have either been measured with precision or for the first time, but the confusing patterns of decays, both above and below open-flavor thresholds, endure and have deepened. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hotand cold-nuclear-matter effects in quark-gluon plasma studies. This review systematically addresses all these matters and concludes by prioritizing directions for ongoing and future efforts.

show abstract

Section: Quarkonium Polarization: a Key Observablesupporting

confidence: 54%

Section: −4mentioning

confidence: 99%

See 1 more Smart Citation

Heavy quarkonium: progress, puzzles, and opportunities

Brambilla¹,

Eidelman²,

Heltsley³

et al. 2011

Advances in the Physics of Particles and Nuclei

103

View full text Add to dashboard Cite

show abstract

“…At large transverse momenta, k ⊥ ≫ Q s , these expressions simplify [24] and the cross-section smoothly reduces to the k ⊥ -factorization result of Collins and Ellis [25] and Catani, Ciafaloni and Hautmann [26]. The k ⊥ -factorization formalism of these authors has been used in several phenomenological studies of heavy quark production at collider energies [27,28,29]. The magnitude of the breaking of k ⊥ -factorization for single quark production was quantified in ref.…”

Section: Introductionmentioning

confidence: 99%

Quark pair production in high energy pA collisions: General features

2006

View full text Add to dashboard Cite

A consistent treatment of both multiple scattering and small x quantum evolution effects on pair production in high energy pA collisions is feasible in the framework of the Color Glass Condensate (CGC) [1]. We first discuss the properties of quark pair production in the classical effective theory where only multiple scattering effects are included. Explicit results are given for pair production as a function of the invariant mass of pairs, the pair momenta, the atomic mass number A and the quark mass. We relate the logarithms that appear in our formulation of pair production to logarithms that appear in the limit of collinear factorization in QCD. Violations of k ⊥ factorization and medium modifications, as represented by the Cronin effect, are also investigated. We next consider how small x quantum evolution (shadowing) effects modify the results for pair production. In particular, we provide results for the rapidity distribution of pairs and the dependence of the Cronin effect on rapidity. We discuss the dependence of our results on the initial conditions for small x evolution and comment on its implications for pair production at RHIC and the LHC.1 URA 2306 du CNRS.

show abstract

“…The k ⊥ -factorization approach has rather successfully described the production of open charm and beauty, as discussed in the previous section, but also hadroproduction of heavy quarkonium states, J/ψ, χ c and Υ mesons, at the Tevatron are well described [95,[113][114][115]. In many cases, however, the data can also be described within the usual collinear parton model, if the relevant next-toleading order QCD corrections are taken into account, or if the so called color-octet mechanism is included.…”

Section: Main Author S Baranovmentioning

confidence: 99%