We study the azimuthal angle dependence of the energy-energy correlators in the back-to-back region for e+e− annihilation and deep inelastic scattering (DIS) processes with general polarization of the proton beam. We define the Collins-type EEC jet functions and demonstrate that the polarization information of the beam and the underlying partons from the hard scattering is propagated into the azimuthal angle dependence of the energy-energy correlators. We also investigate the transverse energy-energy correlators (TEEC) in the small-x regime at the upcoming Electron-Ion Collider (EIC). Focusing on the back-to-back production of electron-hadron pairs in both ep and eA collisions, we establish a factorization theorem. Our analysis reveals that TEEC observables in DIS provide a valuable approach for probing gluon saturation phenomena. Our findings underscore the significance of measuring EEC and TEEC at the EIC, emphasizing how energy correlators can be used to probe transverse momentum dependent structures, gluon saturation and nuclear modifications in high-energy collisions.
Hosts: P. Tadic, B. Mecaj, & M. Kologlu