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The failure of observing the $e^+ e^- \to J/\psi+J/\psi$ events at $B$ factories to date is often attributed to the significant negative order-$\alpha_s$ correction. In this work we compute the ${\cal O}(\alpha^2_s)$ correction to this…

High Energy Physics - Phenomenology · Physics 2023-06-21 Wen-Long Sang , Feng Feng , Yu Jia , Zhewen Mo , Jichen Pan , Jia-Yue Zhang

B->gamma e nu transitions have recently been studied in the framework of QCD factorization. The attractiveness of this channel for such an analysis lies in the fact that, at least in the heavy quark limit, the only hadron involved is the B…

High Energy Physics - Phenomenology · Physics 2009-11-10 Patricia Ball , Emi Kou

We consider the production of $W\gamma$ and $Z\gamma$ pairs at hadron colliders. We report on the complete fully differential computation of radiative corrections at next-to-next-to-leading order (NNLO) in QCD perturbation theory. The…

High Energy Physics - Phenomenology · Physics 2015-04-07 Massimiliano Grazzini , Stefan Kallweit , Dirk Rathlev

The production cross sections of $e^+e^- $ to a heavy quarkonium with $C$-parity even $S-$wave and $P-$wave associated with a photon are analyzed in the framework of non-relativistic Quantum Chromodynamics(NRQCD) factorization formalism.…

High Energy Physics - Phenomenology · Physics 2010-04-15 Wen-Long Sang , Yu-Qi Chen

We directly fit the QCD dimensional transmutation parameter, Lambda MS-bar, to experimental data on e+e- jet observables, making use of next-to-leading order (NLO) perturbative calculations. In this procedure there is no need to mention,…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. J. Burby , C. J. Maxwell

NNLO QCD corrections for the pion electromagnetic form factor at large momentum transfer have been recently performed in [Phys. Rev. Lett. 132, 201901 (2024); Phys. Rev. Lett. 134, 221901 (2025)], revealing that the NLO and NNLO…

High Energy Physics - Phenomenology · Physics 2025-12-29 Sheng-Quan Wang , Zuo-Fen Liao , Jian-Ming Shen , Hua Zhou , Jia-Wei Zhang , Jiang Yan , Xing-Gang Wu , Leonardo Di Giustino

The decay widths of top quark to S-wave $b\bar{c}$ and $b\bar{b}$ bound states are evaluated at the next-to-leading(NLO) accuracy in strong interaction. Numerical calculation shows that the NLO corrections to these processes are remarkable.…

High Energy Physics - Phenomenology · Physics 2014-11-20 Peng Sun , Li-Ping Sun , Cong-Feng Qiao

Within the framework of the perturbative QCD approach, we calculate the time-like $B_cB_c(B_c^*)$ form factors $F(Q^2)$ and $A_2(Q^2)$. We include relativistic corrections and QCD corrections, either of which can give about $20\%$…

High Energy Physics - Phenomenology · Physics 2018-07-18 Yan-Bing Wei , Run-Hui Li , Dan Luo , Cai-Dian Lü , Yue-Long Shen

Based on the factorization framework of nonrelativistic quantum chromodynamics, we study the associated $J/\psi+c+\bar{c}$ photoproduction process at next-to-leading order in $\alpha_s$ and leading order in the velocity expansion. The total…

High Energy Physics - Phenomenology · Physics 2024-05-10 Qi-Ming Feng , Cong-Feng Qiao

We present a detailed analysis on the $B_c$ meson semi-leptonic decays, $B_c \to \eta_c (J/\psi) \ell \nu$, up to next-to-leading order (NLO) QCD correction. We adopt the principle of maximum conformality (PMC) to set the renormalization…

High Energy Physics - Phenomenology · Physics 2014-09-02 Jian-Ming Shen , Xing-Gang Wu , Hong-Hao Ma , Sheng-Quan Wang

We calculate the time-like $\rho$ electromagnetic (EM) form factor in the $k_T$ factorization formalism by including the next-to-leading-order (NLO) corrections of the leading-twist and sub-leading twist contributions. It's observed that…

High Energy Physics - Phenomenology · Physics 2025-01-10 Ya-Lan Zhang , Si-Yu Wang , Chao Wang , Zhen-Jun Xiao , Ya Li

In the framework of potential NRQCD, we obtain the next-to-leading-log renormalization-group running of the matching coefficients for the heavy quarkonium production currents near threshold. This allows to obtain S-wave heavy-quarkonium…

High Energy Physics - Phenomenology · Physics 2009-11-07 Antonio Pineda

It has been a long-standing problem that the rare electromagnetic decay process $J/\psi\to 3\gamma$ is plagued with both large and negative radiative and relativistic corrections. To date it remains futile to make a definite prediction to…

High Energy Physics - Phenomenology · Physics 2013-03-14 Feng Feng , Yu Jia , Wen-Long Sang

One of the main goals of future electron-ion colliders is to improve our understanding of the structure of hadrons. In this letter, we study the exclusive $\eta_c$ production by $\gamma^{*} \gamma$ interactions in $eA$ collisions and…

High Energy Physics - Phenomenology · Physics 2023-08-09 Izabela Babiarz , Victor P. Goncalves , Wolfgang Schäfer , Antoni Szczurek

We report on the perturbative $O(\alpha_s)$ correction to the light-cone QCD sum rule for the $B\to \pi$ transition form factor $f^+$. The correction to the product $f_Bf^+$ in leading twist approximation is found to be about 30%, that is…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. Khodjamirian , R. Rückl , S. Weinzierl , O. Yakovlev

We calculate the cross section of inclusive direct J/psi hadroproduction at next-to-leading order (NLO) within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD), including the full relativistic corrections due to…

High Energy Physics - Phenomenology · Physics 2011-02-02 Mathias Butenschoen , Bernd A. Kniehl

The large $N_c$ limit provides relations that can be used to calculate the $\gamma^\ast N \to \Delta(1232)$ quadrupole form factors at low and intermediate $Q^2$ under the assumption of the pion cloud dominance. There are two limitations in…

High Energy Physics - Phenomenology · Physics 2016-12-13 G. Ramalho

In this paper we present a next-to-next-to-leading order (NNLO) QCD calculation of the processes $pp\rightarrow l^+l^-\gamma$ and $pp\rightarrow \nu\bar\nu\gamma$ that we have implemented in MCFM. Our calculation includes QCD corrections at…

High Energy Physics - Phenomenology · Physics 2018-01-17 John M. Campbell , Tobias Neumann , Ciaran Williams

We study the QCD corrections at next-to-next-to-leading order (NNLO) to the cross section for the hadronic pair-production of top quarks. We present new results in the high-energy limit using the well-known framework of k_t-factorization.…

High Energy Physics - Phenomenology · Physics 2015-06-04 S. Moch , P. Uwer , A. Vogt

We investigate the electromagnetic properties of the fully charm tetraquark states, particularly incorporating contributions from internal gluon radiations. The paper first presents analytical expressions for the next-to-leading-order (NLO)…

High Energy Physics - Phenomenology · Physics 2025-12-29 Xinran Liu , Yefan Wang , Ruilin Zhu
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