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arXiv · 1505.02013

Gravitational form factors and transverse spin sum rule in a light front quark-diquark model in AdS/QCD

Dipankar Chakrabarti·Chandan Mondal·Asmita Mukherjee
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Abstract

The gravitational form factors are related to the matrix elements of the energy-momentum tensor $T^{μν}$. Using the light front wave functions of the scalar quark-diquark model for nucleon predicted by the soft-wall AdS/QCD, we calculate the flavor dependent $A(Q^2)$, $B(Q^2)$ and $\bar{C}(Q^2)$ form factors. We also present all the matrix element of the energy-momentum tensor in a transversely polarized state. Further, we evaluate the matrix element of Pauli-Lubanski operator in this model and show that the intrinsic spin sum rule involves the form factor $\bar{C}$. The longitudinal momentum densities in the transverse impact parameter space are also discussed for both unpolarized and transversely polarized nucleons.

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Dipankar Chakrabarti, Chandan Mondal, Asmita Mukherjee. 2015-05-08. Gravitational form factors and transverse spin sum rule in a light front quark-diquark model in AdS/QCD. https://doi.org/10.1103/physrevd.91.114026

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