$1/Q^2$ power corrections to TMD factorization for Drell-Yan hadronic tensor

Abstract

I calculate $\frac{1}{Q^2}$ power corrections to unpolarized Drell-Yan hadronic tensor for electromagnetic (EM) current at large $N_c$ and demonstrate the EM gauge invariance at this level.

58 pages, 1 figures. Typos corrected, footnote and references added. arXiv admin note: substantial text overlap with arXiv:2012.01588