Quertenmont, Loic
[UCL]
(eng)
Heavy Stable (or long-lived) Charged Particles (HSCP) are predicted by various extensions to the Standard Model of the fundamental interactions among elementary particles. If this prediction reveals to be true, such particles should be produced at the Large Hadron Collider (LHC) and observable with the Compact Muon Solenoid (CMS) detector.
The LHC produced the first pp collisions at √s = 7 TeV at the beginning of April 2010. These first collisions were used to calibrate the detector but also to search for new physics.
If HSCPs are produced in LHC collisions they will have an anomalously high ionization energy loss (dE/dx) that can be measured using the CMS Silicon Strip Tracker (SST). These highly penetrating particles are expected to reach the CMS Muon System. The typical HSCP signature is therefore a high momentum track with an anomalously high dE/dx that reaches the muon system. However, a recent study on the modelling of the interaction of the HSCP with matter claims that certain species of HSCPs are undetectable in the muon system. A complementary search, which does not require the HSCP track to reach the muon system, was therefore developed.
The results of these two model-independent searches for HSCPs produced in pp collisions at √s = 7 TeV are presented in this thesis. The tools needed to exploit the unique HSCP signature are also discussed, including the algorithms for the SST calibration, for identification and mass reconstruction of the particles based on their dE/dx. FROG, an innovative application for data visualization in high energy physics, is also presented.
Bibliographic reference |
Quertenmont, Loic. Search for heavy stable charged particles with the CMS detector at the LHC : from detector commissioning to data analysis. Prom. : Bruno, Giacomo |
Permanent URL |
http://hdl.handle.net/2078.1/68570 |