Searches for Supersymmetric Particles in Final States with Multiple Top and Bottom Quarks with the Atlas Detector

Two of the most prominent searches for supersymmetry at the ATLAS experiment are documented in this PhD thesis, which used up to 80/fb of proton-proton collision data at a center-of-mass energy of 13 TeV during Run 2 (2015-2018). The signals of interest include a high multiplicity of jets produced by the hadronization of b-quarks and significant missing transverse momentum, making them one of the most promising final state signatures for discovering new phenomena at the LHC. The first search focuses on the strong production of a pair of gluinos, with each gluino decaying into a neutralino and a top-antitop-quark pair or a bottom-antibottom-quark pair. The second search targets the pair production of higgsinos, with each higgsino decaying into a gravitino and a Higgs boson, which must decay into a bottom-antibottom-quark pair.

Format: Paperback / softback
Length: 279 pages
Publication date: 03 September 2021
Publisher: Springer Nature Switzerland AG

This comprehensive PhD thesis delves into two groundbreaking searches for supersymmetry conducted at the ATLAS experiment utilizing up to 80/fb of proton-proton collision data at a center-of-mass energy of 13 TeV, generated by the Large Hadron Collider (LHC) during its Run 2 (2015-2018). The focus of these searches lies in the detection of signals featuring a high multiplicity of jets originating from the hadronization of b-quarks, accompanied by significant missing transverse momentum. This remarkable final state signature holds immense potential for the discovery of new phenomena at the LHC.

In the first search, the thesis explores the robust production of a pair of gluinos, where each gluino decays into a neutralino and a top-antitop-quark pair or a bottom-antibottom-quark pair. The utilization of state-of-the-art experimental techniques and analysis strategies at the LHC has yielded some of the most stringent bounds to date on the masses of the gluino, neutralino, and higgsino within the frameworks explored.

The second search centers around the pair production of higgsinos, where each higgsino decays into a gravitino and a Higgs boson. Notably, the Higgs boson is then required to decay into a bottom-antibottom-quark pair. Similar to the first search, these investigations employ cutting-edge experimental techniques and rigorous analysis methodologies, resulting in stringent constraints on the masses of the gluino, neutralino, and higgsino within the models examined.

Through these comprehensive analyses, the thesis contributes significantly to our understanding of supersymmetry and its potential to unveil new physics beyond the Standard Model. The results obtained from these searches have profound implications for our quest to unravel the mysteries of the cosmos and provide insights into the fundamental structure of the universe.

Weight: 462g
Dimension: 235 x 155 (mm)
ISBN-13: 9783030528799
Edition number: 1st ed. 2020