Natural supersymmetry has earned a unique focus in the search for new physics, in part because of its solution to the hierarchy problem. Minimizing fine tuning in this solution often puts the superpartners of the Higgs (higgsino) and top quark (stop) well within LHC reach. In the most natural scenario, the higgsino and stop masses are additionally expected to be close to the masses of their Standard Model partners, known as a compressed spectrum. Small mass splittings in a decay chain present several experimental challenges, since the final state objects are very soft and there is little missing energy. In order to build a sensitive analysis around these difficulties, a variety of new techniques are utilized, including improvements with ISR-assisted topologies using the Recursive Jigsaw Reconstruction (RJR) method. Here, these novel strategies and the idea of naturalness are used to frame the status of stop and higgsino searches with ATLAS and discuss future search prospects.
About the speaker
Julia Gonski is a Ph.D. student and NSF Graduate Research Fellow in the ATLAS group at Harvard University. When not working on jet performance or searching for supersymmetry, Julia is active in science policy and outreach, serving on the Council of the American Physical Society. She also co-directs the blog Particlebites, which summarizes recent publications in high energy physics for all audiences.
More information on Julia's research can be found here.