NRQCD Confronts LHCb Data on Quarkonium Production within Jets

Bain, Reggie; Makris, Yiannis; Mehen, Thomas; Dai, L.; Leibovich, Adam K.

doi:10.1103/physrevlett.119.032002

Cited by 59 publications

(58 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We found that this observable leads to even more discriminative power and it can, thus, provide better constraints for the LDMEs in global fits and more accurate information on the non-perturbative formation of heavy quarkonia. A complimentary study in [40] provided similar conclusions. We encourage the experimentalists to perform such measurements at the LHC and RHIC.…”

Section: Introductionsupporting

confidence: 70%

J/ψ Production and Polarization within a Jet

et al. 2017

View full text Add to dashboard Cite

We study the production and polarization of J/ψ mesons within a jet in proton-proton collisions at the LHC. We define the J/ψ-jet fragmentation function as a ratio of differential jet cross sections with and without the reconstructed J/ψ in the jet. We demonstrate that this is a very useful observable to help explore the J/ψ production mechanism, and to differentiate between different NRQCD global fits based on inclusive J/ψ cross sections. Furthermore, we propose to measure the polarization of J/ψ mesons inside the jet, which can provide even more stringent constraints for the heavy quarkonium production mechanism. Introduction.Understanding the J/ψ production mechanism is one of the most active and challenging subjects in strong interaction physics [1,2]. The most common approach to calculating the J/ψ production cross section in hadronic collisions is the non-relativistic QCD (NRQCD) factorization formalism [3]. In this approach, the heavy quark and anti-quark pair, QQ, is produced at short-distance which can be calculated perturbatively due to the large heavy quark masses. Such a QQ state will then hadronize into a physical J/ψ meson. This transition is non-perturbative, but it can be characterized through a set of universal NRQCD long-distance matrix elements (LDMEs). Global analyses of the world's data on J/ψ production with the next-to-leading order (NLO) calculations in powers of strong coupling constant α s have been performed by several groups [4][5][6][7][8]. Even though all these groups can describe the inclusive J/ψ production cross section, i.e., the p T spectrum, they have not been able to fully explain the polarization of high-p T heavy quarkonia produced at the Tevatron [9][10][11][12] and the LHC [13,14]. Despite of numerous attempts made in the past, the J/ψ polarization remains a puzzle.

show abstract

Section: Introductionsupporting

confidence: 70%

J/ψ Production and Polarization within a Jet

et al. 2017

View full text Add to dashboard Cite

show abstract

“…[32] (after this Letter was submitted, Ref. [59] demonstrated quantitative agreement). The lack of isolation observed for prompt J=ψ production may be related to the long-standing quarkonium polarization puzzle.…”

Section: H Y S I C a L R E V I E W L E T T E R S Week Ending 12 May 2017mentioning

confidence: 82%

Study of J/ψ Production in Jets

Aaij¹,

Ciezarek²,

Collins³

et al. 2017

Phys. Rev. Lett.

View full text Add to dashboard Cite

The production of J=ψ mesons in jets is studied in the forward region of proton-proton collisions using data collected with the LHCb detector at a center-of-mass energy of 13 TeV. The fraction of the jet transverse momentum carried by the J=ψ meson, zðJ=ψÞ ≡ p T ðJ=ψÞ=p T ðjetÞ, is measured using jets with p T ðjetÞ > 20 GeV in the pseudorapidity range 2.5 < ηðjetÞ < 4.0. The observed zðJ=ψÞ distribution for J=ψ mesons produced in b-hadron decays is consistent with expectations. However, the results for prompt J=ψ production do not agree with predictions based on fixed-order nonrelativistic QCD. This is the first measurement of the p T fraction carried by prompt J=ψ mesons in jets at any experiment.

show abstract

“…In Ref. [15] for describing the production of quarkonium within jets in hadronic collisions we convolve the FJF with the corresponding hard scattering process evaluated using the monte-carlo software MadGraph [14],…”

Section: Review Of Fragmenting Jet Functionsmentioning

confidence: 99%

“…Particularly we propose a measurement of the quarkonium transverse momentum with respect to jet axis and we review the theoretical tools developed Figure 1: Predicted z(J/ψ) distribution using GFIP (gray) and FJF (red) for the three choices of LDME as described in the text and the LHCb measurements of z(J/ψ) [16]. Figure taken from [15] in Ref. [23] necessary for this calculation.…”

Section: Review Of Fragmenting Jet Functionsmentioning

confidence: 99%

Transverse Momentum Dependent Fragmenting Jet Functions with Applications to Quarkonium Production

Makris

2018

Proceedings of QCD Evolution 2017 — PoS(QCDEV2017)

Self Cite

View full text Add to dashboard Cite

We briefly review the framework of fragmenting jet functions (FJFs) introduced in soft collinear effective theory (SCET) to describe the fragmentation of an identified hadron within a jet. We illustrate how FJFs can be integrated with the leading power (LP) factorization in non-relativistic quantum chromodynamics (NRQCD) in studies of quarkonium production within jets. We present recent theoretical, experimental, and computational developments. We also present the framework of transverse momentum dependent (TMD) FJFs which describe the fragmentation of a hadron within a jet and the transverse momentum of the identified hadron is measured with respect to the jet axis. We show how the measurement of the transverse momentum spectrum can help discriminate between the leading production mechanisms of J/ψ.

show abstract

NRQCD Confronts LHCb Data on Quarkonium Production within Jets

Cited by 59 publications

References 46 publications

J/ψ Production and Polarization within a Jet

J/ψ Production and Polarization within a Jet

Study of J/ψ Production in Jets

Transverse Momentum Dependent Fragmenting Jet Functions with Applications to Quarkonium Production

Contact Info

Product

Resources

About