All-heavy pentaquarks provide a unique laboratory for exploring the interplay between exotic-hadron structure, heavy-quark dynamics, and perturbative Quantum Chromodynamics (QCD). In this review, we present the completed release of the uncertainty-aware collinear fragmentation-function family PQ5Q1.1, covering both all-charm (P5c) and all-bottom (P5b) states. The extension to the bottom sector follows the resolution of theoretical and numerical issues affecting heavy-bottom fragmentation and completes the public LHAPDF6 release of the PQ5Q1.1 family. The PQ5Q1.1 functions are constructed within a multimodal framework that accounts for both compact multiquark formation and diquark–antiquark–diquark production mechanisms. A replica-based strategy is adopted to quantify perturbative and nonperturbative uncertainties through missing-higher-order variations (F-MHOUs) and controlled modifications of the hadronic wave-function structure (F-NPWF). For phenomenological applications, we employ the data-validated (sym)JETHAD framework to investigate semi-inclusive pentaquark-plus-jet production at NLL/NLO+ accuracy at the High-Luminosity Large Hadron Collider. We present predictions for differential distributions, assessing the impact of fragmentation dynamics, uncertainty propagation, and hadron-structure effects across the charm and bottom sectors. By combining precision fragmentation tools with collider-oriented observables, this review establishes a unified framework connecting heavy-pentaquark spectroscopy, hadronization mechanisms, and high-energy QCD phenomenology.
We present a comprehensive high-energy overview of all-heavy tetraquark production at the High-Luminosity Large Hadron Collider, combining recent advances in heavy-exotic spectroscopy with state-of-the-art fragmentation-based phenomenology. Our study builds upon the newly released TQ4Q2.0 fragmentation framework, which provides a complete leading-power description of fully heavy S-wave tetraquarks with scalar (0++), axial-vector (1+−), and tensor (2++) quantum numbers. The formalism incorporates all active gluon- and heavy-quark-induced production channels within nonrelativistic QCD factorization and implements threshold-aware DGLAP evolution through the HF-NRevo scheme. Particular attention is devoted to the all-bottom sector, whose larger mass scale offers a distinctive laboratory for exploring multiquark formation mechanisms and testing the universality of fragmentation dynamics across heavy-flavor systems. We review the theoretical foundations of the TQ4Q program and discuss the uncertainty budget associated with color-composite long-distance matrix elements and perturbative multiscale variations. Building on this framework, we present precision predictions for bottom tetraquark production in association with jets at HL-LHC energies, obtained within the (sym)JETHAD environment at NLL/NLO+ accuracy. The resulting phenomenology highlights the discovery potential of future high-luminosity measurements and illustrates the impact of modern resummation techniques on rare-hadron observables. This work establishes the TQ4Q2.0 framework as a reliable phenomenological benchmark for collider studies of all-heavy tetraquarks and provides a unified roadmap for future investigations of multiquark dynamics at present and forthcoming hadron facilities.
Heavy quarkonium production inside jets offers a sensitive probe of QCD dynamics and bound-state formation mechanisms. While recent studies demonstrate that charmonium-in-jet observables effectively discriminate among competing nonrelativistic QCD (NRQCD) long-distance matrix element (LDME) sets, whether this discriminating power persists in the bottomonium sector remains an open question. Here, we present the first phenomenological study of $\Upsilon(1S)$, $\Upsilon(2S)$, and $\Upsilon(3S)$ production inside jets using the fragmenting jet function (FJF) framework at next-to-leading order (NLO), incorporating DGLAP evolution, threshold resummation, and feeddown contributions from higher bottomonium states. In sharp contrast to charmonium, we find that bottomonium-in-jet momentum-fraction ($z_H$) distributions exhibit a universal shape that is remarkably insensitive to the choice of LDME sets. We show that this universality stems from the strong dominance of the S-wave spin-triplet color-octet ($^3S_1^{[8]}$) production mechanism reinforced by $\chi_b$ feeddown transitions. Our predictions capture both the characteristic large-$z_H$ peak and the spectral broadening with increasing jet transverse momentum observed in recent CMS measurements. These results establish a clear physical distinction between charmonium and bottomonium fragmentation inside jets, providing a theoretical benchmark for future high-precision measurements at the LHC.
Tae-Won Ha, Hee Sok Chung, D. Kang et al.· 0 citations
We investigate the mechanisms underlying exotic hadron formation via the TQ4Q1.1 set of collinear fragmentation functions for fully charmed or bottomed tetraquarks in three quantum configurations: scalar (\(0^{++}\)), axial vector (\(1^{+-}\)), and tensor (\(2^{++}\)). We adopt leading-power single-parton fragmentation within a nonrelativistic QCD framework tailored to tetraquark Fock states. Initial-scale inputs are constructed from updated gluon and heavy-quark channels, and evolved through threshold-consistent DGLAP within HF-NRevo. We present a systematic implementation of uncertainty propagation from color-composite long-distance matrix elements governing tetraquark hadronization. This study further develops the connection between hadronic structure, precision QCD, and exotic hadron matter.
Published by the Jagiellonian University
2026
authors
F. Celiberto· Acta Physica Polonica B, Pro...· 0 citations
In this manuscript, we present the results of our studies on the exclusive photoproduction of quarkonium-photon pairs with large invariant mass. In our analysis, we focus on the production of the ηcγ and χcJγ pairs in high energy kinematics. We use the Color Glass Condensate (CGC) framework for analysis and demonstrate that at leading order in αs the cross-sections of these processes are determined by the forward dipole scattering amplitude. The kinematic distributions of the produced particles allow us to study the dipole amplitude in detail, making this process a very clean probe for studies of saturation physics. Using phenomenological parametrizations of the dipole amplitudes, we estimate numerically the differential production cross-sections for ηcγ and χcγ in the kinematics of ultraperipheral collisions at the LHC and the future Electron-Ion Collider (EIC). Furthermore, we assess the role of this process as a possible background to the exclusive photoproduction of C-even quarkonia, which is frequently considered as a tool for odderon searches.
M. Siddikov, I. Zemlyakov, M. Roa· Particles· 0 citations
Heavy quarks (charm and beauty) are predominantly produced in hard partonic scatterings, making their cross sections in proton--proton (pp) collisions calculable in perturbative quantum chromodynamics (pQCD) and thus providing stringent tests of pQCD. Furthermore, the associated production of two charm hadrons in a single collision offers a sensitive probe of multiparton interaction dynamics, distinguishing between single parton scattering (SPS) and double parton scattering (DPS) processes. In this contribution, preliminary measurements of prompt D-meson production are reported, together with the final results of the $\rm B^{0}$-meson production cross section down to $p_{\rm T}$ = 1 GeV/$c$ at midrapidity. The rapidity dependence of B-meson production is investigated by computing the ratio with respect to LHCb measurements at forward rapidity. The associated production of $\rm D^{0}$--$\mathrm{J}/\psi$ pairs in pp collisions at $\sqrt{s} = 13.6$ TeV is presented as well, where $\rm D^{0}$ mesons are reconstructed at midrapidity, while $\mathrm{J}/\psi$ candidates are measured at forward rapidity. These measurements are compared with pQCD calculations and phenomenological models, providing crucial constraints on heavy-quark production, hadronisation, and multiparton interaction dynamics.
Deependra Sharma, For The Alice Collaboration· 0 citations
We discuss the factorization of scattering processes near partonic threshold at next-to-leading power (NLP) in the threshold variable $1-z$, with $z \equiv q^2/\hat{s}$. We review the general structure of power-suppressed contributions both in Soft-Collinear Effective Theory (SCET) and in a direct QCD approach, and discuss the definition of NLP jet functions as gauge-invariant operator matrix elements in QCD. As a controlled check of the resulting factorization formula, we verify it explicitly at one and two loops for the massive electromagnetic form factor in the limit $m^2 \ll s$, using the method of regions. We conclude by outlining the two challenges that remain for a systematic resummation of NLP logarithms: the treatment of endpoint divergences in SCET convolutions, and the extension of jet functions to radiative processes capable of describing an arbitrary number of soft-gluon emissions -- the latter being the last missing ingredient for exponentiation, given that the purely soft sector is already understood in terms of generalised webs via the replica trick.
Robin van Bijleveld, J. T. Hoeve, E. Laenen et al.· 0 citations