Heavy quarkonium: progress, puzzles, and opportunities
read the original abstract
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. The plethora of newly-found quarkonium-like 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 c\bar{c}, b\bar{b}, and b\bar{c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hot- and 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.
This paper has not been read by Pith yet.
Forward citations
Cited by 19 Pith papers
-
Next-to-next-to-leading-order QCD corrections to ${}^3S_1^{(8)}$ gluon fragmentation function for quarkonium
First NNLO QCD calculation of the ³S₁⁽⁸⁾ gluon fragmentation function in NRQCD, yielding positive substantial corrections and endpoint logarithms for threshold resummation.
-
Factorizing quarkonium production matrix elements using effective field theory
Factorizes NRQCD production matrix elements for S- and P-wave quarkonia into wavefunctions and universal chromo-electric/magnetic gluon correlators via hybrid vNRQCD/pNRQCD and Hubbard-Stratonovich transformation at l...
-
Semi-analytical results for $e^+e^-\to J/\psi + X_{{\rm non\,}c\bar{c}}$ up to $\mathcal{O}(\alpha_s v^2)$ at B factories
NRQCD calculation of O(α_s), O(v²) and first-time O(α_s v²) corrections to e⁺e⁻ → J/ψ + X_non c c̄, with r = m_c/√s expansions to r⁴⁰, yielding cross section 0.530 pb consistent with Belle but angular parameter deviating >2σ.
-
Bounds on massive graviton-like particles from searches for axion-like particles coupling to photons
Limits on axion-like particles from photon-coupling searches are recast as constraints on massive graviton-like particles across lab, astrophysical, and cosmological experiments using analogous Primakoff and Gertsensh...
-
Probing hot QCD medium with heavy quarkonium in small and large collision systems
A time-dependent Schrödinger equation model reproduces suppression of Υ(nS)/Υ(1S) and ψ(2S)/J/ψ yield ratios versus multiplicity in p-Pb collisions at 8.16 TeV, supporting transient hot QCD medium in small systems.
-
Measurement of $J/\psi$-jet correlations in $pp$ and Pb+Pb collisions at $\sqrt{s_{\text{NN}}}=5.02$ TeV with the ATLAS detector
New measurements of isolated, non-isolated, and inclusive J/ψ yields, nuclear modification factors, and fractions up to 60 GeV in pp and Pb+Pb collisions at 5.02 TeV.
-
Gluon mass and small-x dynamics in hadrons
Introduces a gluon mass and auxiliary scalar field to cancel small-x divergences in the front-form QCD Hamiltonian, yielding confinement for heavy quarks as the mass parameter is sent to zero.
-
Soft Contributions Stabilize NNLO QCD Corrections to Quarkonium Production and Decay
Soft contributions stabilize NNLO QCD corrections for S-wave color-singlet quarkonium processes, yielding better perturbative convergence and experimental agreement.
-
Extraction of charmonium branching fractions from $J/\psi\to\gamma\eta_c$ radiative decays
Proposes new photon line shape and branching fraction extraction method for J/psi to gamma eta_c, claiming compatibility between PDG data correlations and lattice QCD widths via profile scan.
-
Principles and Possibilities for Bound States in Gauge Theory
Temporal gauge fixing and Gauss' law yield an instantaneous confining potential for color-singlet q q-bar states when a non-vanishing boundary condition is imposed at infinity, enabling perturbative hadron calculation...
-
Inclusive charm and bottom quark pair production cross sections at hadron colliders at next-to-next-to-leading-order accuracy
NNLO QCD calculations using the MaunaKea code enhance c cbar and b bbar production cross sections by up to a factor of two over NLO predictions, reduce scale uncertainties, and match experimental data from 10 GeV to 1...
-
Coupled-channel study of the three-body $DDK$ and $D^{*}D^{*}K$
The DDK system supports a deeply bound compact state across wide parameters and possibly a shallow three-body halo state near the D-DK threshold, with negligible D*D*K coupling and no resonances.
-
All-charm tetraquarks at hadron colliders: A high-precision fragmentation perspective
The authors construct and publicly release the TQ4Q2.0 fragmentation functions for all-heavy S-wave tetraquarks via NRQCD factorization, extending prior work with nonconstituent contributions and replica-based uncertainties.
-
Correlation function and bound state from the $K D_{s0}^*(2317)$ interaction
The K D_s0*(2317) system develops a narrow resonance 40 MeV below threshold under the fixed-center molecular assumption, producing a characteristic correlation function for strong attraction.
-
A multi-differential constraint map for quarkonium suppression mechanisms in high-multiplicity pp and pPb collisions
Multi-differential constraint analysis of Υ(nS) suppression in high-multiplicity pp and pPb collisions favors an early, globally correlated, topology-sensitive mechanism over local-density or total-multiplicity control.
-
Principles and Possibilities for Bound States in Gauge Theory
Canonical quantization in temporal gauge produces instantaneous bound-state potentials in QED and QCD; a non-vanishing boundary condition on the longitudinal gluon field at infinity yields confinement for color single...
-
$D\bar{D}^\ast$-$\pi J/\psi$ scatterings of coupled channels for $Z_c(3900)$ channel
Quark-exchange interactions at short distances dominate the coupled-channel scattering amplitudes for Zc(3900) over meson exchanges in an effective hadron-quark model.
-
Three-body molecular states composed of $D^{(*)}$ and two nucleons
The DNN system forms a robust compact bound state in the I=1/2 (1^-) channel across cutoffs, while D*NN exhibits spin-dependent bound states in 0^-, 1^-, and 2^- channels with no resonances found.
-
Meson-Hybrid Mixing in Vector ($1^{--}$) and Axial Vector ($1^{++}$) Charmonium
QCD Laplace sum-rules analysis of meson-hybrid cross correlators probes charmonium resonances for nonzero coupling to both conventional and hybrid currents as a mixing signal.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.