This series of lectures is primarily associated with collider physics where one seeks to learn about fundamental interactions by colliding particles at high energy and by studying the products of these collisions. In this sense, talking about jets is essentially talking about the highly-energetic quarks and gluons produced in these collisions and their dynamics governed by the strong interaction.
This is ubiquitous in all recent colliders and jets are (to varying degrees) present in almost all aspects of collider phenomenology. This set of lectures is mostly two-folded: on one side it will try to give a taste of the broad range of aspects and applications of jet physics, on the other side it will show how it is rooted in (perturbative) Quantum Chromodynamics (QCD).
Lecture 2/5 - All-order calculations in QCD:
In a way, jets cover energy scales ranging from the high energy of the collision all the way down to the non-perturbative/hadronisation scale of QCD. A consequence is that jet physics often need all-order calculations in (perturbative) QCD. I will spend this lecture showing how such a calculation can be organised, taking the case of the jet mass as an example.
In terms of reference material, most of material covered in the lectures can be found in the set of Springer Lecture Notes "Looking Inside Jets: an introduction to jet substructure and boosted-object phenomenology" (arXiv:1901.10342).
Some of the material covered in the first lecture can also be found in the review "Towards Jetography" (arXiv:0906.1833) as well as in standard QCD textbooks (e.g. "QCD and collider physics" by Keith Ellis, James Stirling and Brian Webber).
The first and third lectures will be oriented towards concepts and phenomenological aspects. While keeping physics consequences as a target, lectures 2, 4 and 5 will focus more on calculations in the context of perturbative QCD. Note however that this is a tentative plan: I am happy to make adjustments if, in the course of the lectures, it appears that some aspects are worth exploring in more details or some different directions worth being introduced.