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Related papers: Automated One-loop Computation in Quarkonium Proce…

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The next-to-leading order (NLO) quantum chromodynamics (QCD) corrections for $\chi_{cJ}(^3P_J^{[1]},^3S_1^{[8]})$, the P-wave charmoniums inclusive production at $B$ factories are calculated utilizing the non-relativistic QCD (NRQCD)…

High Energy Physics - Phenomenology · Physics 2015-06-03 Long-Bin Chen , Jun Jiang , Cong-Feng Qiao

For the calculation of multi-loop Feynman integrals, a novel numerical method, the Direct Computation Method (DCM) is developed. It is a combination of a numerical integration and a series extrapolation. In principle, DCM can handle…

High Energy Physics - Phenomenology · Physics 2012-01-31 K. Kato , E. de Doncker , N. Hamaguchi , T. Ishikawa , T. Koike , Y. Kurihara , Y. Shimizu , F. Yuasa

We study a recently-proposed approach to the numerical evaluation of multi-loop Feynman integrals using available sector decomposition programs. As our main example, we consider the two-loop integrals for the $\alpha \alpha_s$ corrections…

High Energy Physics - Phenomenology · Physics 2017-11-08 Andreas von Manteuffel , Robert M. Schabinger

We calculate convergent 3-loop Feynman diagrams containing a single massive loop equipped with twist $\tau =2$ local operator insertions corresponding to spin $N$. They contribute to the massive operator matrix elements in QCD describing…

High Energy Physics - Phenomenology · Physics 2015-06-19 Jakob Ablinger , Johannes Blümlein , Clemens Raab , Carsten Schneider , Fabian Wißbrock

This thesis can be divided into several parts. The first one consists in a detailed historical review of quarkonium physics, centered on the different production models successively introduced. Then comes a review of the currently available…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. P. Lansberg

Feynman loop integrals are a key ingredient for the calculation of higher order radiation effects, and are responsible for reliable and accurate theoretical prediction. We improve the efficiency of numerical integration in sector…

High Energy Physics - Phenomenology · Physics 2016-01-12 Zhao Li , Jian Wang , Qi-Shu Yan , Xiaoran Zhao

We review the current status of perturbative corrections in QCD at four loops for scattering processes with space- and time-like kinematics at colliders, with specific focus on deep-inelastic scattering and electron-positron annihilation.…

High Energy Physics - Phenomenology · Physics 2021-04-19 S. Moch , V. Magerya

Within NRQCD factorization framework, in this work we compute, at the lowest order in velocity expansion, the next-to-leading-order (NLO) perturbative corrections to the short-distance coefficients associated with heavy quark fragmentation…

High Energy Physics - Phenomenology · Physics 2021-07-28 Feng Feng , Yu Jia , Wen-Long Sang

FDCHQHP is a Fortran package to calculate the transverse momentum (p_t) distribution of yield and polarization for heavy quarkonium hadroproduction at next-to-leading-order (NLO) based on non-relativistic QCD(NRQCD) framework. It contains…

High Energy Physics - Phenomenology · Physics 2015-06-19 Lu-Ping Wan , Jian-Xiong Wang

We present a new program package for calculating one-loop Feynman integrals, based on a new method avoiding Feynman parametrization and the contraction due to Passarino and Veltman. The package is calculating one-, two- and three-point…

High Energy Physics - Phenomenology · Physics 2007-05-23 Lars Brucher , Johannes Franzkowski

We compute the next-to-next-to-leading order (NNLO) QCD corrections to the hadronic decay rates of the pseudoscalar quarkonia, at the lowest order in velocity expansion. The validity of NRQCD factorization for inclusive quarkonium decay…

High Energy Physics - Phenomenology · Physics 2017-12-27 Feng Feng , Yu Jia , Wen-Long Sang

Calculation of hadronization, decay or scattering processes at non-zero temperatures and densities within the Nambu-Jona-Lasinio-like models requires some techniques for computation of Feynmann diagrams. Decomposition of Feynman diagrams at…

High Energy Physics - Phenomenology · Physics 2021-11-10 A. S. Khvorostukhin

I describe the NRQCD factorization approach to the inclusive production of heavy quarkonium, contrasting it with the color-singlet and color evaporation models. These approaches differ dramatically in their assumptions about the roles…

High Energy Physics - Phenomenology · Physics 2009-10-31 Eric Braaten

We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…

High Energy Physics - Phenomenology · Physics 2009-07-29 J. Gluza , A. Mitov , S. Moch , T. Riemann

Image processing is one of the most promising applications for quantum machine learning (QML). Quanvolutional Neural Networks with non-trainable parameters are the preferred solution to run on current and near future quantum devices. The…

Quantum Physics · Physics 2024-10-10 Daniele Lizzio Bosco , Beatrice Portelli , Giuseppe Serra

We present a program that implements the OPP reduction method to extract the coefficients of the one-loop scalar integrals from a user defined (sub)-amplitude or Feynman Diagram, as well as the rational terms coming from the 4-dimensional…

High Energy Physics - Phenomenology · Physics 2011-05-05 Giovanni Ossola , Costas G. Papadopoulos , Roberto Pittau

One-way measurement based quantum computations (1WQC) may describe unitary transformations, via a composition of CPTP maps which are not all unitary themselves. This motivates the following decision problems: Is it possible to determine…

Quantum Physics · Physics 2009-10-22 Niel de Beaudrap

I discuss the status of the computation of the two-loop QCD corrections to top-quark pair production associated with a jet at hadron colliders. This amplitude is a missing ingredient for next-to-next-to-leading order (NNLO) QCD predictions.…

High Energy Physics - Phenomenology · Physics 2024-11-19 Colomba Brancaccio

We present the analytical results for the two-loop form factors needed for $\chi_{Q,J}$ production and decay. We consider the two-loop corrections to the process $\gamma \gamma \leftrightarrow {^3 P_J^{[1]}}$, that has been known only…

High Energy Physics - Phenomenology · Physics 2025-06-10 Melih A. Ozcelik

We develop a formalism for computing inclusive production cross sections of heavy quarkonia based on the nonrelativistic QCD and the potential nonrelativistic QCD effective field theories. Our formalism applies to strongly coupled…

High Energy Physics - Phenomenology · Physics 2021-09-09 Nora Brambilla , Hee Sok Chung , Antonio Vairo