Evidence for the Standard Model Higgs Boson Decaying to One Semi-hadronically Decaying Tau and One Leptonically Decaying Tau at ATLAS

Date created: 
2014-05-29
Identifier: 
etd8426
Keywords: 
Physics
Particle physics
Higgs boson
ATLAS
LHC
Standard Model
Abstract: 

This thesis reports the search for the Higgs boson decaying to a pair of tau leptons, where one tau decays leptonically and the other decays semi-hadronically. The search was conducted by the ATLAS experiment on the proton-proton collisions supplied by the LHC in 2012. It is complicated by background from a mix of known processes from the Standard Model of Particle Physics. It makes use of boosted decision trees to separate the Higgs signal from the background. The gluon-gluon fusion and the vector boson fusion production mechanisms are searched for separately. The statistical significance of the excess observed over the background-only hypothesis is 3.3 standard deviations, and reaches 4.1 standard deviations when combined with other ditau channels. The observed signal appears fully compatible with the Higgs boson of the Standard Model.

Document type: 
Thesis
Rights: 
Copyright remains with the author. The author granted permission for the file to be printed and for the text to be copied and pasted.
Senior supervisor: 
Dugan O'Neil
Department: 
Science: Department of Physics
Thesis type: 
(Thesis) Ph.D.
Statistics: