Author(s): Liang Dong, Shen Fang, Jun Gao, Hai Tao Li, Ding Yu Shao, and Yu Jiao Zhu We present the first calculation of hadron production in deep-inelastic scattering (DIS) at finite transverse momentum to next-to-next-to-leading order (NNLO) in perturbative QCD. To overcome the long-standing challenge of infrared divergences in semi-inclusive processes with identified final state … [Phys. Rev. Lett. 137, 081902] Published Fri Aug 21, 2026