(California Institute of Technology (US)), Jamie Antonelli
(The Ohio State University (US))
Understanding Hadronisation at PP Colliders
From recent decisive measurements at LHC, it is becoming increasingly clear that hadronisation in pp collisions at high energies must involve new dynamical phenomena which are absent (or at least highly suppressed) in e+e-. Taken collectively, the evidence amounts to an observation of a breakdown of jet universality, with important consequences not only for QCD modelling (and understanding) but also for any derived purposes for which the accuracy of such modelling plays a role, such as jet energy scale calibrations and hadronisation corrections in general, in particular for precision hadronic quantities such as the top quark mass extraction. I will provide a pedestrian-level walkthrough of the models and the (main) observational evidence, with the aim of spurring discussion of what further salient measurements now could be made, to aid in distinguishing cleanly between possible physics scenarios. It will be especially relevant to find clean probes to distinguish whether the new physics is fundamentally ‘thermal’ or ‘non-thermal’ in origin.