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Related papers: Resolution of the LHCb $\eta_c$ anomaly

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The inclusive production of pseudoscalar heavy quarkoniua ($\eta_c,~\eta_b$ and $B_c$) via photon-photon fusion in heavy ion ultraperipheral collision (UPC) are calculated to QCD next-to-leading order in the framework of non-relativistic…

High Energy Physics - Phenomenology · Physics 2024-10-10 Jun Jiang , Shi-Yuan Li , Xiao Liang , Yan-Rui Liu , Cong-Feng Qiao , Zong-Guo Si , Hao Yang

We study the photoproduction of the heavy quarkonium at the future International Linear Collider (ILC) within the nonrelativistic QCD theory. We focus on the production channel via the subprocess $\gamma\gamma \to |[Q\bar{Q'}]_{\bf…

High Energy Physics - Phenomenology · Physics 2014-10-30 Gu Chen , Xing-Gang Wu , Hai-Bing Fu , Hua-Yong Han , Zhan Sun

Using the NRQCD factorization formalism, we calculate the total cross section for the photoproduction of h_c mesons. We include color-octet and color-singlet mechanisms as well as next-to-leading order perturbative QCD corrections. The…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sean Fleming , Thomas Mehen

In heavy quarkonium production, the measured ratio $R_{c \bar c}=\sigma[J/\psi+ c\bar c + X]/\sigma[J/\psi +X]$ at B factories is much larger than existing theoretical predictions. To clarify this discrepancy, in nonrelativistic QCD (NRQCD)…

High Energy Physics - Phenomenology · Physics 2009-06-19 Yan-Qing Ma , Yu-Jie Zhang , Kuang-Ta Chao

We present a fully-differential calculation of the NNLO QCD corrections to the t-channel mechanism for producing single top quarks at the LHC. We work in the structure function approximation, computing QCD corrections to the light- and…

High Energy Physics - Phenomenology · Physics 2015-06-19 Mathias Brucherseifer , Fabrizio Caola , Kirill Melnikov

We analyze the recent LHCb measurement of the distribution of the fraction of the transverse momentum, $z(J/\psi)$, carried by the $J/\psi$ within a jet. LHCb data is compared to analytic calculations using the fragmenting jet function…

High Energy Physics - Phenomenology · Physics 2017-07-26 Reggie Bain , Lin Dai , Adam Leibovich , Yiannis Makris , Thomas Mehen

We proceed to the first study of $\eta_c'$ prompt hadroproduction at next-to-leading order in $\alpha_s$. Based on heavy-quark-spin symmetry, which is systematically used in quarkonium-production phenomenology, we demonstrate that prompt…

High Energy Physics - Phenomenology · Physics 2018-10-10 Jean-Philippe Lansberg , Hua-Sheng Shao , Hong-Fei Zhang

Unlike the bewildering situation in the $\gamma\gamma^*\to \pi$ form factor, a widespread view is that perturbative QCD can decently account for the recent \textsc{BaBar} measurement of $\gamma\gamma^*\to \eta_c$ transition form factor. The…

High Energy Physics - Phenomenology · Physics 2015-12-02 Feng Feng , Yu Jia , Wen-Long Sang

The quarkonium production in association with a heavy-quark pair of the same flavor was found plays an important role in various production schemes, let alone it provides a distinctive signature that could be studied in experiment. Within…

High Energy Physics - Phenomenology · Physics 2025-07-29 Qi-Ming Feng , Cong-Feng Qiao

The $J/\psi+Z^0$ associated production at the LHC is an important process in investigating the color-octet mechanism of non-relativistic QCD in describing the processes involving heavy quarkonium. We calculate the next-to-leading order…

High Energy Physics - Phenomenology · Physics 2012-11-20 Song Mao , Ma Wen-Gan , Li Gang , Zhang Ren-You , Guo Lei

The observation of unpolarized quarkonium production in high energy pp collisions, at mid rapidity, implies a significant violation of the non-relativistic QCD (NRQCD) velocity scaling rules. A precise experimental confirmation of this…

High Energy Physics - Phenomenology · Physics 2019-06-26 Pietro Faccioli , Carlos Lourenco

Non-Relativistic QCD (NRQCD) has provided a consistent framework for the physics of quarkonia. The colour-octet Fock components predicted by NRQCD have important implications for the phenomenology of quarkonium production in experiments. We…

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

We calculate the next-to-leading order (NLO) QCD corrections to the $J/\psi +W$ production at the LHC, and provide the theoretical distribution of the $J/\psi$ transverse momentum. Our results show that the differential cross section…

High Energy Physics - Phenomenology · Physics 2011-02-25 Li Gang , Song Mao , Zhang Ren-You , Ma Wen-Gan

Heavy quarkonium production in the framework of the nonrelativistic quantum chromodynamics and leading order of the parton Reggeization approach at the Tevatron and LHC Colliders is discussed. The new results, which are reviewed in this…

High Energy Physics - Phenomenology · Physics 2014-10-24 Maxim Nefedov , Vladimir Saleev

We provide a detailed study of prompt double $J/\psi$ production within the non-relativistic QCD (NRQCD) framework in proton-proton collisions at the LHC. We confront the recent LHC data with the results obtained at leading-order (LO) in…

High Energy Physics - Phenomenology · Physics 2016-06-13 S. P. Baranov , Amir H. Rezaeian

We develop the formalism for production of a fully heavy tetraquark and apply it to the calculation of $pp\to T_{4c}+X$ cross-sections. We demonstrate that the production cross-section of a fully heavy tetraquark, even if it is a…

High Energy Physics - Phenomenology · Physics 2025-02-05 Ilia Belov , Alessandro Giachino , Elena Santopinto

Recent discrepancies between theoretical predictions and experimental data in multi-lepton plus $b$-jets analyses for the $t\bar{t}W^\pm$ process, as reported by the ATLAS collaboration, have indicated that more accurate theoretical…

High Energy Physics - Phenomenology · Physics 2021-08-04 Giuseppe Bevilacqua , Huan-Yu Bi , Heribertus Bayu Hartanto , Manfred Kraus , Jasmina Nasufi , Malgorzata Worek

In this talk I review the recent progress made in the calculations of quarkonia production in fixed target experiments. NRQCD organizes the calculations in a systematic expansion in $\alpha_s$ and $v$, the relative velocity between the…

High Energy Physics - Phenomenology · Physics 2011-04-15 Ira Z. Rothstein

Recent measurements of J/psi production in e^+ e^- colliders pose a challenge to the NRQCD factorization theorem for quarkonium production. Discrepancies between leading order calculations of color-octet contributions and the momentum…

High Energy Physics - Phenomenology · Physics 2014-11-17 Thomas Mehen

Based on the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD), we calculate the production cross section for the charmonium and the bottomonium produced by the hard photoproduction processes and fragmentation…

High Energy Physics - Phenomenology · Physics 2017-06-13 Gong-Ming Yu , Yan-Bing Cai , Yun-De Li , Jian-Song Wang