Naive $T$-odd Drell-Yan angular coefficients as a probe of the dimension-8 SMEFT

Abstract

We propose the ``naive" $T$-odd Collins-Soper moments in the Drell-Yan process as probes of previously unexplored directions in the Standard Model Effective Field Theory (SMEFT) parameter space. We show that the moments $A_6$ and $A_7$ in the high invariant mass and transverse momentum region are sensitive to dimension-8 $CP$-odd semi-leptonic four-fermion operators with an additional gluon field strength tensor. Using the projected integrated luminosity of a future high-luminosity LHC, we show that effective ultraviolet scales in the few-TeV range can be probed with this process.