My review covers quite extensively the topic, as it is not constrained in length as other reviews usually are. At 76 pages, and with 500 references, it aims to be the main reference on this type of physics for the next five years or so - at least, this is the stipulation with PPNP. Whether I managed to make it such, it is something to be judged by others.
The plan of the work is as follows:
- Chapter 1 is an introduction, which gives an overview of the topic and its importance in particle physics;
- Chapter 2 gives an overview of the theoretical models which predict the existence of new states with a significant branching fraction to boson pairs;
- Chapter 3 describes the experimental facilities where the recent measurements have been conducted; this is mostly the LHC and the ATLAS and CMS experiments.
- Chapter 4 presents a broad overview of the reconstruction procedures of the final state objects of interest for the searches;
- Chapter 5 discusses the experimental techniques of relevance for the detection of diboson decays, including statistical issues connected to the extraction of evidence from the data;
- Chapter 6 offers a brief overview of pre-LHC searches, and then considers the experimental results of all signatures of new resonances decaying in standard model elementary bosons, dividing them in separate disjunct categories: events only containing W and Z bosons as decay signature, events containing photons, events including one Higgs boson in the final state, and finally events with gluons in the final state.
- Chapter 7 finally summarizes the status of the research in the field.
There remains only for me to offer you a quote from the final section:
Whatever machine will inherit the LHC leadership at the high-energy frontier, it will highly benefit from the phenomenological and experimental studies and from the analysis techniques that have been developed there over the course of the past decade for the production of results such as those described in this review. We find of particular signicance those belonging to five macro-areas of research.
The first is the development of new calculational tools that have allowed for more precise predictions of the phenomenology of parton collisions, in particular in complex final states with many hadronic jets. The baseline for most processes is now the next-to-leading order, with many processes computed and modeled to Next-to-Next-to-Leading Order (NNLO), and some even to three-loop accuracy ; parton-level MC programs that include those calculations have greatly improved the understanding of experimental data and supported all BSM searches. The second is constituted by statistical methods devised to extract inference on the presence of small localized signals from likelihood fits to smooth mass distributions, when account needs to be taken of a large number of nuisance parameters. The third area, which is undergoing an explosive expansion inside and outside HEP, is the one of machine learning methods which lend themselves excellently to the challenging classication and regression use cases that are common in particle physics research. The fourth is represented by particle-flow-based reconstruction techniques of high-level objects, which has proven crucial for the precise measurement of hadronic jets in high-pile-up circumstances, as well as for the high-efficiency identification of difficult signatures such as hadronically-decaying tau leptons. The fifth area includes all procedures that allow the tagging of heavy objects within wide hadronic jets of very high energy, by pruning calorimeter clusters of their soft contributions and extracting information on their origin from their substructure. Guidance on the design requirements of the next generation of particle detectors will come in particular from the latter two macro-areas above, as they call for both very high granularity and redundant detection of energy deposits in the calorimeters, as well as a precise tracking in very strong magnetic fields capable of "fanning out" the soft components of hadronic jets.
Having spent a considerable part of my time last year in writing this article, I hope you will give it a look and remember to cite it in your future work!
Tommaso Dorigo is an experimental particle physicist who works for the INFN at the University of Padova, and collaborates with the CMS experiment at the CERN LHC. He coordinates the European network AMVA4NewPhysics as well as research in accelerator-based physics for INFN-Padova, and is an editor of the journal Reviews in Physics. In 2016 Dorigo published the book “Anomaly! Collider physics and the quest for new phenomena at Fermilab”. You can get a copy of the book on Amazon.