Searches for Dark Matter and Large Extra Dimensions in Monojet Final States with the ATLAS Experiment
2016 (English)Doctoral thesis, monograph (Other academic)
This thesis presents searches for evidence for Weakly Interacting Massive Particles (WIMPs) and Extra Dimensions in proton-proton collisions recorded by the ATLAS experiment at the CERN Large Hadron Collider (LHC). The WIMP is one of the main candidates to constitute the particle content of Dark Matter. Extra Dimensions are introduced in several theories in order to explain the apparent weakness of gravity when compared to the other interactions in Nature. Theories with WIMPs as well as Extra Dimensions can manifest themselves at the LHC, with experimental signatures characterized by an energetic hadronic jet associated with large missing momentum. These signatures are known as monojet signatures, and are investigated in this thesis.
The first analysis is performed using L = 20.3 fb-1 of proton-proton collisions at √s = 8 TeV recorded in the ATLAS Run 1. The second analysis is performed using L = 3.2 fb-1 of proton-proton collisions at √s = 13 TeV recorded in the ATLAS Run 2. No significant excess over the expected background is found in either of the analyses. New exclusion limits are set at 95% confidence level on Dark Matter particle production. New limits are also set on graviton production in the so-called ADD scenario with Extra Dimensions.
Place, publisher, year, edition, pages
Stockholm: Department of Physics, Stockholm University , 2016. , 229 p.
particle physics, bsm, gravity, extra dimensions, dark matter, ATLAS, LHC
Research subject Physics
IdentifiersURN: urn:nbn:se:su:diva-129384ISBN: 978-91-7649-429-5OAI: oai:DiVA.org:su-129384DiVA: diva2:922224
2016-06-14, sal FB52, Albanova Universitetscentrum, Roslagstullsbacken 21, Stockholm, 13:00 (English)
Rahatlou, Shahram, Associate Professor
Clement, Christophe, Docent