Probing new physics in events with two same-charge tau leptons produced in association with two jets with the ATLAS detector

Snigdho Chakraborty will use the data collected with the ATLAS detector at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland) for his thesis. The ATLAS collaboration involves more than 4000 scientists, engineers, and students from hundreds of institutes in about 40 countries. His thesis will focus on studies of the production of events with two leptons with the same electric charge in association with jets. The primary objective is the search for Heavy Neutral Leptons and other new physics phenomena in events with two tau leptons. In doing so, he will have to understand the backgrounds to this analysis, and develop novel methods (including the use of deep machine learning) to reduce them and increase the sensitivity of the search. Snigdho Chakraborty will also work on the study of processes related to the main topic, such as, among others, that of same-sign W bosons produced in association with two jets, which is sensitive to the mechanism of Electroweak Symmetry Breaking and of which no measurement using tau leptons has been performed yet. Snigdho Chakraborty will also contribute to the effort conducted in the ATLAS Combined Performance group on Trigger and Jets and Missing Energy to derive ML-based jet calibrations. The completion of this task will lead to his qualification as an ATLAS author.