Jet algorithms, flavour & infrared safety

• Ludovic Scyboz (University of Oxford)
• Ludovic Scyboz
• Ludovic Michel Scyboz
• Ludovic Michel Scyboz (Max-Planck-Institut fur Physik (DE))
• Ludovic Michel Scyboz (Monash University)

Most particle-collider analyses use clustering algorithms to bundle together the sprays of radiation we observe in the detector, to define so-called “jets”. These objects are used as input to the analyses, but they are in fact necessary from a theoretical viewpoint, as they regulate the divergences that arise naturally in Quantum Chromodynamics (a concept called infrared safety). For a long time it was unclear how to define the quantum “flavour” of a jet, reflecting the flavour of the quark initiating the jet, in a similarly safe way. In this talk I will review recent developments in the design of flavoured jet algorithms, with a focus on infrared safety and applicability in the experiments. I will discuss a range of recently-proposed flavoured jet algorithms whose labels may in principle be used as input to train ML taggers.