Photon Leading Twist Transverse Momentum Dependent Parton Distributions
Published in EPJA special edition on Topical Spin-1 observables.
S. Puhan, N. Kumar and H. Dahiya
Eur. Phys. J. A 61 (2025)
January 01, 2025
Abstract
In this work, we have calculated the photon leading-twist T-even transverse momentum dependent parton distribution functions (TMDs). For these calculations, we have treated photon as a state of quark anti-quark pair and represent the TMDs in explicit form of helicity amplitudes. We have presented all the T-even TMDs for the photon being massless (real) and massive (virtual). We have also compared our longitudinally and transversely polarized TMDs results for different photon masses. The collinear parton distribution functions (PDFs) have been predicted for both the real and virtual photon cases. The results for the unpolarized PDF of our calculations are in good agreement with other model predictions. In addition to this, we have also discussed the spin-spin correlations between the quark and photon.
Summary
Calculates all leading-twist T-even photon TMDs using light-front wave functions, treating the photon as a quark-antiquark Fock state. Compares results for real vs. virtual photons and discusses spin-spin correlations.
Authors: S. Puhan, N. Kumar and H. Dahiya
Published in: Eur. Phys. J. A 61 (2025)

