Transverse spin effects and light-quark dipole moments at lepton colliders

TL;DR

This paper introduces a novel method to probe light-quark dipole moments at lepton colliders through azimuthal asymmetries in dihadron production, offering improved sensitivity over existing constraints.

Contribution

It proposes a new experimental approach using azimuthal asymmetries in dihadron production to measure light-quark dipole moments at lepton colliders.

Findings

Method can disentangle up and down quark dipole moments.

Potential to improve current constraints by 10 to 100 times.

Sensitive to both real and imaginary parts of dipole couplings.

Abstract

We propose to probe light-quark dipole interactions at lepton colliders using the azimuthal asymmetry of a collinear dihadron pair $(h_1h_2)$ produced in association with another hadron $h'$. This asymmetry, arising from quantum interference in the quark spin space, is exclusively sensitive to dipole interactions at the leading power of the new physics scale and simultaneously probes both the real and imaginary components of the dipole couplings. By combining all possible channels of $h'$, this method allows for disentangling the up and down quark dipole moments and has the potential to significantly strengthen current constraints by one to two orders of magnitude.