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Related papers: Color-Octet Fragmentation and the psi' Surplus at …

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We report that, unlike most inclusive quarkonium-production processes, the production rate for p p -> J/psi+Upsilon+X dominantly depends on two not well-known long-distance nonrelativistic QCD matrix elements, <O_8^{J/psi}(^3S_1)> and…

High Energy Physics - Phenomenology · Physics 2011-03-22 P. Ko , Chaehyun Yu , Jungil Lee

We consider the prompt hadroproduction of J/psi, psi' and the Upsilon (1S,2S,3S) states caused by the fusion of a symmetric colour-octet two-gluon state and an additional gluon. The cross sections are calculated in leading-order…

High Energy Physics - Phenomenology · Physics 2011-03-23 V. A. Khoze , A. D. Martin , M. G. Ryskin , W. J. Stirling

We review the physics of quarkonium production at high energy colliders, with a specific emphasis on production $via$ fragmentation. We discuss the fragmentation picture for the production of quarkonia at large-$p_T$ at the Tevatron and…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. Sridhar

We consider the contribution of new strongly interacting sector, with a characteristic scale of half a TeV, to top quark production at the Tevatron. The color-octet, isosinglet analog of the $\rho$ meson in this theory is produced copiously…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. V. Ramana

We consider the contribution of new strongly interacting sector, with a characteristic scale of half a TeV, to top quark production at the Tevatron. The color-octet, isosinglet analog of the $\rho$ meson in this theory is produced copiously…

High Energy Physics - Phenomenology · Physics 2008-12-25 B. Holdom , M. V. Ramana

We calculate \alpha^{2}\alpha_{s}^{2} order QED contribution to J/\psi production in pp(\bar{p})\to J/\psi+c\bar{c} color-singlet process at the Tevatron and LHC in the framework of non-relativistic QCD. The contribution of the interference…

High Energy Physics - Phenomenology · Physics 2009-10-29 Zhi-Guo He , Rong Li , Jian-Xiong Wang

The $t$-channel exchange of two gluons in a color singlet state represents the lowest order approximation to the Pomeron. This exchange mechanism is thought to also explain the formation of rapidity gaps in dijet events at the Tevatron. At…

High Energy Physics - Phenomenology · Physics 2009-09-25 H. N. Chehime , D. Zeppenfeld

Nonrelativistic QCD provides a systematic approach for inclusive decays and productions of a quarkonium. By taking color-octet components into account, the approach can explain the $\psi'$-anomaly at Tevatron, where the measured production…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Y. Liu , J. P. Ma , X. G. Wu

We compute the contributions to large-$p_T$ $J/\psi$ production at HERA coming from fragmentation of gluons and charm quarks. We find that the charm quark fragmentation contribution dominates over the direct production of $J/\psi$ via…

High Energy Physics - Phenomenology · Physics 2009-10-28 R. M. Godbole , D. P. Roy , K. Sridhar

We calculate the direct production rate of $J/\psi$ in top quark decays. The color-octet $J/\psi$ production via $t\rightarrow W^+ b J/\psi$ is shown to have a large branching ratio of order $1.5\times 10^{-4}$, which is over an order of…

High Energy Physics - Phenomenology · Physics 2009-10-28 Cong-feng Qiao , Kuang-Ta Chao

The direct production rates of $D$-wave charmonia in the decays of $Z^0$ is evaluated. The color-octet production processes $Z^0\rightarrow ^3D_J(c\bar c) q\bar q$ are shown to have distinctively large branching ratios, the same order of…

High Energy Physics - Phenomenology · Physics 2019-08-17 Cong-feng Qiao , Feng Yuan , Kuang-Ta Chao

Approximately taking into account the higher-order effects due to multiple-gluon initial-state radiation, we extract from the latest Tevatron data of prompt J/psi hadroproduction the leading colour-octet matrix elements within the…

High Energy Physics - Phenomenology · Physics 2011-08-11 Bernd A. Kniehl , Gustav Kramer

We calculate the fragmentation function for charm quark into J/psi at the QCD next-to-leading-order (NLO) and find that the produced J/psi is of larger momentum fraction than it is at the leading-order. Based on the fragmentation function…

High Energy Physics - Phenomenology · Physics 2011-02-02 Bin Gong , Rong Li , Jian-Xiong Wang

We consider the J/Psi production in proton (deuteron) -- nucleus collisions at high energies. We argue that the production mechanism in this case is different from that in pp collisions due to gluon saturation in the nucleus and formation…

High Energy Physics - Phenomenology · Physics 2008-11-26 Dmitri Kharzeev , Kirill Tuchin

We present the first complete study of $\Upsilon$ and prompt $J/\psi$ production from single-parton scattering, including the complete $\mathcal{O}(\alpha_S^6)$ color-singlet contribution, the $\mathcal{O}(\alpha_S^2\alpha^2)$ electroweak…

High Energy Physics - Phenomenology · Physics 2016-08-10 Hua-Sheng Shao , Yu-Jie Zhang

In this paper, we discuss the prompt j/psi production at e^+e^- colliders via color-singlet and color-octet production mechanisms. The color-singlet production processes include 1) e^+e^- to J/\psi gg; 2) e^+e^- to J/\psi c\bar{c}; 3)…

High Energy Physics - Phenomenology · Physics 2009-10-30 Feng Yuan , Cong-Feng Qiao , Kuang-Ta Chao

Within the framework of leading power factorization formalism of nonrelativistic quantum chromodynamics, we calculate the jet fragmentation function for $J/\psi$ production in proton-proton (pp) collisions ranging from $\sqrt{s}=500$ GeV to…

High Energy Physics - Phenomenology · Physics 2024-03-20 Shan-Liang Zhang , Hongxi Xing

A collision of a light meson and a charmonium produces quarks and antiquarks first, then the charm quark fragments into a charmed hadron, and finally three or more mesons are produced. This is the mechanism that we consider and propose to…

High Energy Physics - Phenomenology · Physics 2017-07-28 Shi-Tao Ji , Xiao-Ming Xu , H. J. Weber

We consider the prompt double $J/\psi$ production in $pp$ collisions at the LHC in the framework of $k_T$-factorization QCD approach. Using the fragmentation mechanism, we evaluate the color octet contributions to the production cross…

High Energy Physics - Phenomenology · Physics 2020-12-02 A. A. Prokhorov , A. V. Lipatov , M. A. Malyshev , S. P. Baranov

We study the production of $J/\psi$ vector mesons as a function of charged hadron multiplicity in p+p and p+Pb collisions at LHC energies. We employ the color glass condensate framework, using running coupling Balitsky-Kovchegov evolved…

High Energy Physics - Phenomenology · Physics 2022-03-09 Farid Salazar , Björn Schenke , Alba Soto-Ontoso