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相关论文: Spin-2 Form Factors at Three Loop in QCD

200 篇论文

We investigate the spin contribution to light baryon ground states in three inequivalent large-$N$ limits: 't Hooft, QCD antisymmetric and QCD symmetric. Our framework is a constituent quark model with a relativistic Hamiltonian containing…

高能物理 - 唯象学 · 物理学 2012-02-29 Fabien Buisseret , Nicolas Matagne , Claude Semay

We calculate Sudakov-type form factors for isolated spin-1/2 particles (fermions) entering non-Abelian gauge-field systems. We consider both the on- and the off-mass-shell case using a methodology which rests on a worldline casting of field…

高能物理 - 唯象学 · 物理学 2009-10-30 G. C. Gellas , A. I. Karanikas , C. N. Ktorides , N. G. Stefanis

The calculation of the next-to-leading order QCD corrections to the production of a neutral Higgs-boson pair is briefly summarized. The dominant production mechanism is gluon fusion via top-quark loops, so that the QCD corrections can be…

高能物理 - 唯象学 · 物理学 2007-05-23 S. Dawson , S. Dittmaier , M. Spira

In this work, the electromagnetic and gravitational form factors of a spin-$3/2$ particle, $\Delta$ resonance, are simultaneously calculated with the help of a relativistic covariant quark-diquark approach. The two kinds of form factors are…

高能物理 - 唯象学 · 物理学 2022-01-24 Dongyan Fu , Bao-Dong Sun , Yubing Dong

Parallel to the construction of gauge invariant spin and orbital angular momentum for QED in paper (I) of this series, we present here an analogous but non-trivial solution for QCD. Explicitly gauge invariant spin and orbital angular…

高能物理 - 唯象学 · 物理学 2015-06-30 X. S. Chen , X. F. Lü , W. M. Sun , F. Wang , T. Goldman

A general discussion is presented of the single logarithmic soft factor that appears in two scale QCD observables in processes involving four partons. We treat it as the ``fifth form factor'', accompanying the four collinear singular…

高能物理 - 唯象学 · 物理学 2009-11-11 Yu. L. Dokshitzer , G. Marchesini

We present the analytic form of the two-loop five-gluon scattering amplitudes in QCD for a complete set of independent helicity configurations of external gluons. These include the first analytic results for five-point two-loop amplitudes…

高能物理 - 唯象学 · 物理学 2019-03-06 S. Abreu , J. Dormans , F. Febres Cordero , H. Ita , B. Page

Transition form factors $F_{P\gamma^*\gamma^{(*)}}$ of pseudoscalar mesons are studied within the framework of the domain model of confinement, chiral symmetry breaking and hadronization. In this model, the QCD vacuum is described by the…

高能物理 - 唯象学 · 物理学 2017-05-03 Sergei N. Nedelko , Vladimir E. Voronin

We consider the Z Q Qbar vertex to second order in the QCD coupling for an on-shell massive quark-antiquark pair and for arbitrary momentum transfer of the Z boson. We present closed analytic expressions for the two parity-violating form…

高能物理 - 唯象学 · 物理学 2010-04-05 W. Bernreuther , R. Bonciani , T. Gehrmann , R. Heinesch , T. Leineweber , P. Mastrolia , E. Remiddi

The complete two-loop correction to the quark propagator, consisting of the spider, rainbow, gluon bubble and quark bubble diagrams, is evaluated in the noncovariant light-cone gauge (lcg). (The overlapping self-energy diagram had already…

高能物理 - 理论 · 物理学 2015-06-26 George Leibbrandt , Jimmy D. Williams

Parton evolution equations in QCD are controlled by the anomalous dimensions of gauge-invariant twist-two spin-$N$ quark and gluon operators. Under renormalization, these mix with gauge-variant operators of the same quantum numbers,…

高能物理 - 唯象学 · 物理学 2024-12-11 G. Falcioni , F. Herzog , S. Moch , S. Van Thurenhout

Spin-1 particles, is a fundamental bound state for the two quarks, and play a crucial role in elucidating the electromagnetic properties within the realm of hadronic physics. Their intrinsic relativistic nature mandates a quantum field…

高能物理 - 唯象学 · 物理学 2026-02-18 J. P. B. C. de Melo

We compute three-loop corrections to the Higgs-gluon form factor, incorporating the top quark mass dependence. Our method is based on the combination of expansions around the top threshold and for large top quark mass, using conformal…

高能物理 - 唯象学 · 物理学 2020-09-18 Joshua Davies , Ramona Groeber , Andreas Maier , Thomas Rauh , Matthias Steinhauser

In the heavy quark limit, the form factors for semileptonic and rare radiative B decays into light mesons are related by heavy quark spin symmetry. Here we compute the leading corrections of order \Lambda/m_Q to these symmetry relations,…

高能物理 - 唯象学 · 物理学 2009-11-07 Benjamin Grinstein , Dan Pirjol

In the framework of quantum gravity propagating in large extra dimensions, we analyze the inclusive radiative emission of Kaluza-Klein spin-2 gravitons in the two-fermions decays of massive gauge bosons, heavy quarks, Higgs bosons, and in…

高能物理 - 唯象学 · 物理学 2010-04-05 E. Gabrielli , B. Mele

The associated production of a Higgs boson with a b quark is a discovery mode for an MSSM Higgs boson at large tan beta. We compute the SUSY QCD corrections from gluino and squark loops to this process and combine them with the order…

高能物理 - 唯象学 · 物理学 2008-11-26 S. Dawson , C. B. Jackson

We present the NLO (two-loop) QCD corrections to Higgs boson pair production in gluon fusion within Standard Model Effective Theory (SMEFT), including also squared dimension-6 operators and double insertions of operators. The different…

高能物理 - 唯象学 · 物理学 2022-07-19 Gudrun Heinrich , Jannis Lang , Ludovic Scyboz

We present preliminary results of a determination of the semileptonic form factor for the decay of pseudoscalar heavy-light mesons to pseudoscalar light-light mesons in full QCD. In this preliminary study we focus on the effects of…

高能物理 - 格点 · 物理学 2008-11-26 C. Bernard , C. DeTar , Steven Gottlieb , E. Gregory , Urs Heller , C. McNeile , J. Osborn , R. Sugar , D. Toussaint

We study the six classical event-shape observables in hadronic Higgs decays at next-to-leading order in QCD. To this end, we consider the decay of on-shell Higgs bosons to three partons, taking into account both the Yukawa-induced decay to…

高能物理 - 唯象学 · 物理学 2022-06-22 Guglielmo Coloretti , Aude Gehrmann-De Ridder , Christian T Preuss

I present results for the resummation of soft and collinear gluon contributions to QCD hard-scattering cross sections at two loops. This requires the calculation of UV and IR divergences through two loops and the construction of soft…

高能物理 - 唯象学 · 物理学 2010-11-19 Nikolaos Kidonakis