Related papers: Gluon fragmentation into S-wave heavy quarkonium
We discuss diffractive dissociation of gluons into heavy quark pairs. The particular mechanism is similar to the diffractive dissociation of virtual photons into quarks, which drives diffractive deep inelastic production of charm in the…
Hadronization of heavy quarks reveals various unusual features. Gluon radiation by a heavy quark originated from a hard process, ceases shortly on a distance of the order of few fm. Due to the dead-cone effect a heavy quark radiates only a…
The dominant production mechanism for ${\bar b} c$ bound states in high energy processes is the production of a high energy ${\bar b}$ or $c$ quark, followed by its fragmentation into the ${\bar b} c$ state. We calculate the fragmentation…
Gravitational form factors (GFFs) of hadrons encode essential information about the internal distributions of mass, spin, pressure, and shear among their quark and gluon constituents. We compute the quark and gluon GFFs of the proton using…
We discuss diffractive dissociation of gluons into heavy quark pairs. The particular mechanism is similar to the diffractive dissociation of virtual photons into quarks. The amplitude for the $g p \to Q \bar Q p$ is derived in the impact…
Study of the polarized heavy quarkonium production in recently proposed QCD factorization formalism requires knowledge of a large number of input fragmentation functions (FFs) from a single parton or a heavy quark-antiquark pair to a…
We derive the twist-3 gluon fragmentation function (FF) contribution to the transversely polarized hyperon production in semi-inclusive deep inelastic scattering, $ep\to e\Lambda^\uparrow X$, in the leading order (LO) with respect to the…
Inspired by the recent measurements of the $\eta_c$ meson production at LHC, we investigate the relativistic correction effect for the fragmentation function of the gluon into $\eta_c$, which constitutes the crucial nonperturbative elements…
We derive the transverse momentum dependent (TMD) factorization for heavy quark pair production in deep inelastic scattering, where the total transverse momentum is much smaller than the invariant mass of the pair. The factorization is…
We present the first calculation at next-to-leading order (NLO) in $\alpha_s$ of a fragmentation function into quarkonium whose form at leading order is a nontrivial function of $z$, namely the fragmentation function for a gluon into a…
Description of hadronic reactions at high energies is conventionally done on basis of QCD factoriza- tion so that factorization convolutions involve non-perturbative inputs mimicking non-perturbative contributions and perturbative evolution…
We address quarkonium formation at moderate to large transverse momenta, where the single-parton collinear fragmentation prevails over the short-distance emission, directly from the hard sub-scattering, of the constituent heavy-quark pair.…
We perform a perturbative QCD analysis of the gluonic gravitational form factors (GFFs) of the proton and pion at large momentum transfer. We derive the explicit factorization formula of the GFFs in terms of the distribution amplitudes of…
It is demonstrated that the fragmentation functions at large momentum fraction play a key role in hard hadron production from relativistic proton-proton collisions. We find that this region of the fragmentation functions is not strongly…
Double parton fragmentation is a process in which a pair of partons produced in the short-distance process hadronize into the final state hadron. This process is important for quarkonium production when the transverse momentum is much…
Inspired by the recent near-threshold $J/\psi$ photoproduction measurements, we discuss gluon gravitational form factors (GFFs) and internal properties of the proton. This work presents a complete analysis of the proton gluon GFFs…
We derive the gluon initiated contribution to the initial condition for the perturbative fragmentation function of a heavy quark through order O(\alpha_s^2) in the MS-bar scheme. This result is needed for the resummation with…
We present for first time the computation at large $q_T$ (or small $b_T$) matching coefficients of Transverse Momentum Dependent Parton Distribution Function (TMDPDF) for linearly polarised to the integrated gluon distribution at…
We study the process $qq\rightarrow qqg$ at lowest order in QCD perturbation theory to understand gluon radiation in the fragmentation region of relativistic heavy-ion collisions. We arrive at a formula for gluon multiplicity that…
We calculate the gravitational form factors (GFFs) and pressure, shear and energy distributions for a quark state dressed with a gluon at one loop in QCD. We use the light-front Hamiltonian approach. In the light-front gauge, we use a…