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Gluon generalized transverse momentum dependent parton distributions and Wigner functions of the proton

Dipankar Chakrabarti1,*, Bheemsehan Gurjar1,†, Asmita Mukherjee2,‡, and Kauship Saha1,§

  • *Contact author: dipankar@iitk.ac.in
  • †Contact author: gbheem@iitk.ac.in
  • ‡Contact author: asmita@phy.iitb.ac.in
  • §Contact author: kauships24@iitk.ac.in
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Phys. Rev. D 112, 114031 – Published 19 December, 2025

DOI: https://doi.org/10.1103/f5tn-lw8v

Abstract

We present a calculation of the leading-twist (twist-2) generalized transverse momentum distributions (GTMDs) for unpolarized and longitudinally polarized gluons in the proton, using a recently developed light-front gluon spectator model inspired by the soft-wall AdS/QCD prediction. We calculate the gluon GTMDs for nonzero skewness, using overlaps in terms of light-front wave functions. We also compute the gluon Wigner distributions for various polarization configurations of the proton target, including unpolarized, longitudinally polarized, and transversely polarized states. We present these Wigner distributions and the associated spin densities in both the transverse momentum plane and the transverse impact parameter plane. Furthermore, we evaluate the gluon orbital angular momentum and spin-orbit correlations, and extract the generalized parton distribution and transverse momentum-dependent distribution limits of the GTMDs.

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Outline

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Phys. Rev. D 112, 114031– Published 19 December, 2025
  • Received 25 September 2025
  • Accepted 3 December 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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