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Scalar, vector, and tensor form factors of pion and kaon

Satyajit Puhan* and Harleen Dahiya†

  • *Contact author: puhansatyajit@gmail.com
  • †Contact author: dahiyah@nitj.ac.in
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Phys. Rev. D 111, 114039 – Published 30 June, 2025

DOI: https://doi.org/10.1103/2wpb-jgkc

Abstract

We calculate the possible scalar, vector, and tensor form factors (FFs) for pion and kaon in the light-cone quark model (LCQM). These FFs are calculated from the leading and subleading twist generalized parton distribution functions (GPDs) of the pion and kaon. The vector and tensor FFs correspond to twist-2 GPDs, whereas the scalar FFs correspond to twist-3 scalar GPDs. We calculate the FFs from the GPDs quark-quark correlator and express them in the form of light-front wave functions. The behavior of these FFs was found to be in agreement with experimental data, other model predictions, and lattice simulation results. We have also calculated the charge radii corresponding to different FFs and compared them with other models, lattice simulation results, and experimental data. The scalar radii of the pion and kaon of our model are found to be 0.528 and 0.409 fm, respectively.

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Phys. Rev. D 111, 114039– Published 30 June, 2025
  • Received 6 May 2025
  • Accepted 16 June 2025
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