相关论文: Electromagnetic Form Factors and the Localization …
We analyze the proton electromagnetic form factor ratio $R(Q^{2})=QF_2(Q^{2})/F_1(Q^{2})$ as a function of momentum transfer $Q^{2}$ within perturbative QCD. We find that the prediction for $R(Q^{2})$ at large momentum transfer $Q$ depends…
Skew density matrices can be diagonalized to yield probability interpretation. The power-counting prediction of perturbative QCD is found consistent with recent CEBAF data on $F_2(Q^2)/F_1(Q^2)$
Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents; indeed, recent proton…
I present an extraction of generalized parton distributions from selected data on the electromagnetic nucleon form factors. The extracted distributions can in particular be used to quantify the contribution to the proton spin from the total…
Elastic nucleon form factors constrain the spatial distribution of quarks in the impact parameter plane. A recent analysis found that the average impact parameter of quarks strongly depends on their longitudinal momentum, and obtained an…
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…
The electromagnetic form factors of the proton are obtained using a particular realization of QCD in the large $N_c$ limit (${QCD}_{\infty}$), which sums up the infinite number of zero-width resonances to yield an Euler's Beta function…
The electromagnetic nucleon form factors provide constraints on generalized quark distributions. Key results of the study presented here are a strong dependence of the average impact parameter of quarks on their longitudinal momentum…
The quark orbital angular momentum component of proton spin, $L_q$, can be defined in QCD as the integral of a Wigner phase space distribution weighting the cross product of the quark's transverse position and momentum. It can also be…
The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electron-nucleon scattering. These form factors are functions of the squared…
Quark orbital angular momentum in the proton is evaluated via a Lattice QCD calculation of the second Mellin moment of the twist-3 generalized parton distribution $\widetilde{E}_{2T} $ in the forward limit. The connection between this…
It is known how to access information on quark orbital angular momentum from generalized parton distribution functions, in a certain specified framework. It is intuitively expected, that such information can be accessed also through…
We study the unpolarized and the helicity dependent generalized parton distributions (GPDs) for the valence quarks of the proton in both momentum space and position space within the basis light-front quantization (BLFQ) framework. The GPDs…
Precise measurements of the proton electromagnetic form factor ratio $R = \mu_p G_E^p/G_M^p$ using the polarization transfer method at Jefferson Lab have revolutionized the understanding of nucleon structure by revealing the strong decrease…
While the total orbital angular momentum (OAM) of a definite quark flavor in a longitudinally-polarized nucleon can be obtained through a sum rule involving twist-two generalized parton distribution (GPDs), its distribution as a function of…
We study the form factors of the quark tensor currents in the pion at large squared momentum transfer Q^2. It turns out that certain form factors can be evaluated using collinear factorization, whereas others receive important contributions…
We present an updated extraction of the proton electromagnetic form factor ratio, mu_p G_E/G_M, at low Q^2. The form factors are sensitive to the spatial distribution of the proton, and precise measurements can be used to constrain models…
We have recently examined the static properties of the baryon octet (magnetic moments and axial vector coupling constants) in a generalized quark model in which the angular momentum of a polarized nucleon is partly spin $\langle S_z…
We study the orbital angular momentum structure of the quarks inside the proton. By employing the light-cone diquark model and the overlap representation formalism, we calculate the chiral-even generalized parton distribution functions…
The momentum distributions of the constituent quarks inside the nucleon and the prominent electroproduced nucleon resonances are investigated in the two most sophisticated, available quark potential models, based respectively on the…