Optimal kinematic observables are often defined in specific frames and then approximated at the reconstruction level. We show how multi-dimensional unfolding methods allow us to reconstruct these observables in their proper rest frame and in a probabilistically faithful way. We illustrate our approach with a measurement of a CP-phase in the top Yukawa coupling. Our method makes use of key advantages of generative unfolding, but as a constructed observable it fits into standard LHC analysis frameworks.
@article{arxiv.2308.00027,
title = {Returning CP-Observables to The Frames They Belong},
author = {Jona Ackerschott and Rahool Kumar Barman and Dorival Gonçalves and Theo Heimel and Tilman Plehn},
journal= {arXiv preprint arXiv:2308.00027},
year = {2024}
}