Nucleon parton distributions in a light-front quark model

Continuing with our analysis of parton distributions in the nucleon, we extend our light-front quark model in order to obtain both the helicity independent and helicity dependent parton distributions, analytically matching the results of global fits at the initial scale $\mu \sim 1$ GeV, and which also contain the correct Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution. We also calculate the transverse parton, Wigner and Husimi distributions from a unified point of view, using our light-front wave functions and expressing them in terms of the parton distributions $q_v(x)$ and $\delta q_v(x)$. Our results are very relevant for the current and future program of the COMPASS experiment at SPS (CERN)

Nuclear physics in soft-wall AdS/QCD: Deuteron electromagnetic form factors

We present a high-quality description of the deuteron electromagnetic form factors in a soft-wall AdS/QCD approach. We first propose an effective action describing the dynamics of the deuteron in the presence of an external vector field. Based on this action the deuteron electromagnetic form factors are calculated, displaying the correct 1/Q^10 power scaling for large Q^2 values. This finding is consistent with quark counting rules and the earlier observation that this result holds in confining gauge/gravity duals. The Q^2 dependence of the deuteron form factors is defined by a single and universal scale parameter kappa, which is fixed from data.Comment: 6 page

Nucleon resonances in AdS/QCD

We describe the electroproduction of the N(1440) Roper resonance in soft-wall AdS/QCD. The Roper resonance is identified as the first radially excited state of the nucleon, where higher-Fock states in addition to the three-quark component are included. The main conclusion is that the leading 3q component plays the dominant role in the description of electroproduction properties of this resonance: form factors, helicity amplitudes and charge densities. The obtained results are in good agreement with the recent results of the CLAS Collaboration at JLab.Comment: 20 pages. arXiv admin note: text overlap with arXiv:1204.661

Some Hadronic Properties from Light Front Holography

Using ideas from Light Front Holography, we discuss the calculation of hadronic properties. In this talk I will pay special attention to hadronic masses and the nucleon helicity-independent generalized parton distributions of quarks in the zero skewness caseComment: Prepared for NSTAR2011. The 8th International Workshop on the Physics of Excited Nucleons. May 17-20, 2011. Thomas Jefferson National Accelerator Facility. Newport News, Virginia, US