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Related papers: Angular momentum decomposition from a QED example

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We continue our work on the light-front formulation of quarkonium $\gamma^* \gamma$ transition form factors, extending the formalism to $J^{PC} = 2^{++}$ tensor meson states. We present an analysis of $\gamma^* \gamma \to \chi_{c2}$…

High Energy Physics - Phenomenology · Physics 2024-02-22 Izabela Babiarz , Roman Pasechnik , Wolfgang Schäfer , Antoni Szczurek

We investigate the predictive power of a relativistic quark model formulated on the light-front. The nucleon electromagnetic form factors, the semileptonic weak decays of the hyperons and the magnetic moments of both baryon octet and…

High Energy Physics - Phenomenology · Physics 2011-04-15 Felix Schlumpf

We formulate the coupling between fermion spin and background electromagnetic fields using form factors. We show that the vacuum form factors at tree level reproduce the spin polarization effects found in chiral kinetic theory. The vacuum…

High Energy Physics - Phenomenology · Physics 2024-03-26 Shu Lin , Jiayuan Tian

We reanalyze the $B\to M$ tensor form factors in a covariant light-front quark model, where $M$ represents a vector meson $V$, an axial-vector meson $A$, or a tensor meson $T$. The treatment of masses and mixing angles in the $K_{1A,1B}$…

High Energy Physics - Phenomenology · Physics 2015-03-13 Hai-Yang Cheng , Chun-Khiang Chua

Predictions for the electromagnetic form factors of the Lambda$, Sigma and Xi hyperons are presented. The numerical calculations are performed within the framework of the fully relativistic constituent-quark model developed by the Bonn…

Nuclear Theory · Physics 2009-11-10 T. Van Cauteren , D. Merten , T. Corthals , S. Janssen , B. Metsch , H. -R. Petry , J. Ryckebusch

We compute the electromagnetic form factors of the proton and neutron using lattice QCD. We employ $N_\mathrm{f}$=2+1+1 twisted mass clover-improved fermions with quark masses tuned to their physical values. Three ensembles with lattice…

High Energy Physics - Lattice · Physics 2025-07-29 Constantia Alexandrou , Simone Bacchio , Giannis Koutsou , Bhavna Prasad , Gregoris Spanoudes

The electromagnetic and gravitational form factors of $\Omega^-$, a spin-3/2 hyperon composed of three $s$ quarks, are calculated by using a covariant quark-diquark approach. The model parameters are determined by fitting to the form…

High Energy Physics - Phenomenology · Physics 2023-06-21 Dongyan Fu , JiaQi Wang , Yubing Dong

A model is developed for electromagnetic form factors of the charged and neutral K-mesons. The formalism is based on ChPT Lagrangians with vector mesons. The form factors, calculated without fitting parameters, are in a good agreement with…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. A. Ivashyn , A. Yu. Korchin

Ultracold neutral bosons in a rapidly rotating atomic trap have been predicted to exhibit fractional quantum Hall-like states. We describe how the composite fermion theory, used in the description of the fractional quantum Hall effect for…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 N. Regnault , C. C. Chang , Th. Jolicoeur , J. K. Jain

Using the equations of motion of QCD and Lorentz invariance relations, we show a new, more direct way of obtaining the decomposition of the proton's quark transverse angular momentum into its spin and orbital components. The new…

High Energy Physics - Phenomenology · Physics 2024-10-30 Osamah Alkasassbeh , Abha Rajan , Michael Engelhardt , Simonetta Liuti

The electromagnetic form factor of the kaon meson is calculated in the light-cone formalism of the relativistic constituent quark model. The calculated $K^+$ form factor is consistent with almost all of the available experimental data at…

High Energy Physics - Phenomenology · Physics 2007-05-23 Bo-Wen Xiao , Xin Qian , Bo-Qiang Ma

QCD sum rules for the determination of form factors of $\Lambda_b$ and $\Lambda_c$ semileptonic decays are investigated. With a form for the baryonic current appropriate for the limits of the heavy quark symmetries, the different tensor…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. S. Marques de Carvalho , F. S. Navarra , M. Nielsen , E. Ferreira , H. G. Dosch

We derive a sum rule for the total quark angular momentum of a spin-one hadronic system within a gauge invariant decomposition of the hadron's spin. We show that the total angular momentum can be measured through deeply virtual Compton…

High Energy Physics - Phenomenology · Physics 2015-03-17 Swadhin K. Taneja , Kunal Kathuria , Simonetta Liuti , Gary R. Goldstein

We study the covariant version of the quark-parton model, in which the general rules of the angular momentum composition are accurately taken into account. We demonstrate how these rules affect the relativistic interplay between the quark…

High Energy Physics - Phenomenology · Physics 2014-04-07 Petr Zavada

We analyze the problem of spin decomposition for an interacting system from a natural perspective of constructing angular momentum eigenstates. We split, from the total angular momentum operator, a proper part which can be separately…

High Energy Physics - Phenomenology · Physics 2011-06-01 Xiang-Song Chen , Wei-Min Sun , Fan Wang , T. Goldman

We present the Schmidt decomposition for arbitrary wavefunctions of two indistinguishable bosons, extending the recent studies of entanglement or quantum correlations for two fermion systems [J. Schliemann et al., Phys. Rev. B {\bf 63},…

Quantum Physics · Physics 2016-09-08 R. Paskauskas , L. You

Light-cone sum rules are used to investigate the electromagnetic form factors of the $\Lambda$ and $\Sigma$ baryons by using the Ioffe type interpolating currents. The sum rules are affected to some extent by the choice of the interpolating…

High Energy Physics - Phenomenology · Physics 2009-07-09 Yong-Lu Liu , Ming-Qiu Huang

We calculate the gravitational form factors (GFFs) and pressure, shear and energy distributions for a quark state dressed with a gluon at one loop in QCD. We use the light-front Hamiltonian approach. In the light-front gauge, we use a…

High Energy Physics - Phenomenology · Physics 2022-04-06 Jai More , Asmita Mukherjee , Sreeraj Nair , Sudeep Saha

The angular momentum of the physical electron, modelled as a Dirac fermion coupled to the electromagnetic field, is found to be hbar/2, the same as that of a bare Dirac fermion and independent of the size of the electric charge.

Quantum Physics · Physics 2009-04-29 A. M. Stewart

We investigate the form factors and decay rates for the semileptonic decays of the kaon($K_{l3})$ using the light-front quark model. The form factors $f_{\pm}(q^{2})$ are calculated in $q^{+}=0$ frame and analytically continued to the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ho-Meoyng Choi , Chueng-Ryong Ji