Searching for exotic Higgs boson decays using a low mass double b-tagger

This dissertation presents the development, calibration, and application of a newly developed double b-tagger for use in the context of exotic Higgs decays. After the discovery of the Higgs boson at the Large Hadron Collider, an effort to measure its properties in detail has ensued. Current measurements only constrain non- Standard Model or “exotic” Higgs decays to about < 26%. Allowing the Higgs to decay into new particles could remedy some outstanding problems in the Standard Model like dark matter or the matter/anti-matter asymmetry in the universe. Thus, an exciting window of opportunity exists for new physics. The exotic Higgs decays investigated in this work have the Higgs decay into a new spin-zero particle, a. The a-boson then decays into a pair of b-quarks. For low a masses, the b-quarks from the same parent a tend to be collimated. This results in signatures that previous ATLAS reconstruction techniques could not efficiently find. With a newly developed tagger, the H → 2a → 4b search in the low mass regime was able to be performed.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2019

Author dc:creator

• Khader, Mazin Woodrow

Contributors dc:contributor

• Martinez Outschoorn, Verena I
• Pitts, Kevin T.
• Shelton, Jessie
• Cooper, Stephen L

• Higgs
• Exotic Higgs
• High Energy Physics
• Particle Physics, Associated Production
• Double B-Tagging
• g->bb Calibration
• Merged Search

Statement dc:rights

• Copyright 2019 Mazin Woodrow Khader

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/104862

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/104862