Related papers: Relativistic correction to gluon fragmentation fun…
We compute the contributions due to gluon and heavy-quark fragmentation to quarkonium production at large transverse momentum in $\bar p p$ and $p p$ collisions. For inclusive $J/\psi$ production, there is a large contribution from the $g…
In this paper we make a systematic study of the semileptonic decays $B/B_s \to (\eta,\etar, G)(l^+l^-,l\bar{\nu},\nu\bar{\nu})$ by employing the perturbative QCD (pQCD) factorization approach. The next-to-leading-order (NLO) contributions…
We study heavy quarkonium production associated with gluons in $\rm e^+e^-$ annihilation as an illustration of the perturbative QCD (pQCD) factorization approach, which incorporates the first nonleading power in the energy of the produced…
We compute the O(alpha_s) QCD corrections to the partonic process gg -> t-tbar-Z at the LHC. This partonic channel is the dominant component of the scattering process pp -> t-tbar-Z, which will be important for measuring the t-tbar-Z…
The leading order non-relativistic QCD result for the quarkonium-hadron interaction cross section is derived by using the QCD factorization formula combined with the Bethe-Salpeter amplitude for the heavy quark bound state. Our result shows…
We critically reexamine the formalism for treating the leading-twist contributions from the two-gluon Fock components occurring in hard processes that involve eta and eta' mesons and establish a consistent set of conventions for the…
In the paper, we calculate the fragmentation functions for a quark to fragment into a spin-singlet quarkonium, where the flavor of the initial quark is different from that of the constituent quark in the quarkonium. The ultraviolet…
In this paper, we investigate the inclusive diffractive hadroproduction for $\rm \eta_{c}$ and $\rm \eta_{b}$ at the LHC energies. Based on the NRQCD factorization formalism and the resolved-Pomeron model for the quarkonium production…
Based on the NRQCD factorization formalism, we calculate the next-to-next-to-leading order QCD corrections to the heavy quarkonium $\eta_c (\eta_b)$ production associated with a photon at electron-positron colliders. By matching the…
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 present the even-N moments N =< 20 of the fourth-order (N^3LO) contribution P_{gq}^(3)(x) to the quark-to-gluon splitting function in perturbative QCD. These moments, obtained by analytically computing off-shell operator matrix elements…
The approach of nonrelativistic QCD(NRQCD) factorization was proposed to study inclusive production of a quarkonium. It is widely used and successful. However, a recent study of gluon fragmentation into a quarkonium at two-loop level shows…
Toponium production at future hadron colliders is investigated. Perturbative QCD corrections to the production cross section for gluon fusion are calculated as well as the contributions from gluon-quark and quark-antiquark collisions to the…
We compute the NLO QCD corrections to the loop-induced gluon fusion contribution in $W^+W^-$ production at the LHC. We consider the full leptonic process $pp\to \ell^+\ell^{\prime\, -}\nu_{\ell}{\bar\nu}_{\ell^\prime}+X$, by including…
In the framework of the $k_T$-factorization, the prompt production of $\eta_c$ mesons at the LHC conditions is studied. Our consideration is based on the off-shell amplitudes for hard partonic subprocesses and on the nonrelativistic QCD…
The fragmentation functions of quarks and gluons into photons are studied beyond the Leading Logarithm approximation. We address the nature of the initial conditions of the evolution equation solutions and study problems related to…
Within the nonrelativistic quantum chromodynamics (NRQCD) factorization formalism, we compute the relativistic corrections to the exclusive decays of bottomonia with even charge conjugation parity into $S$-wave charmonium pairs at leading…
We perform an all-order analysis of double-logarithmic corrections to the so-called soft-overlap contribution to heavy-to-light transition form factors at large hadronic recoil. Specifically, we study $B_c \to \eta_c$ transitions within a…
Inclusive production of a quarkonium $\eta_{c,b}$ in hadron collisions at low transverse momentum can be used to extract various Transverse-Momentum-Dependent(TMD) gluon distributions of hadrons, provided the TMD factorization for the…
We explore how the positivity of the P_T-integrated eta_c-hadroproduction cross-section computed at NLO in alpha_s can set up constraints on the x-dependence of gluon PDFs at low scales.