Thesis

High-performance timing detectors for the CMS upgrade at the High-Luminosity LHC and searches for new physics processes

• Call:

  PT-CERN Call 2022/2

• Academic Year:

  2022

• Domain:

  Astrophysics

• Supervisor:

  Michele Gallinaro

• Co-Supervisor:

  Jonathan Hollar

• Institution:

  Universidade de Lisboa

• Host Institution:

  Laboratório de Instrumentação e Física Experimental de Partículas

• Abstract:

  After the successful first runs of the LHC where the Higgs boson was discovered, the collider and its experiments are gearing up to produce and collect a ten-fold larger data set which will extend the sensitivity to new physics in direct and indirect searches for processes with low production cross sections and harder signatures. This dataset will considerably improve the precision in the measurement of properties of the Higgs boson, including the possibility to measure its triple self-coupling for the first time. To achieve the high intensity in the second phase of the LHC, the machine is expected to provide unprecedented luminosity of around 5x10^34 cm^{-2} s^{-1} with an average of 140 to 200 collisions occurring each bunch crossing. This poses a challenge to the detectors which will have to cope with a harsh radiation environment and will be subject to a high flux of is also a challenge for the reconstruction of the events to be acquired and used to improve the measurement of the Higgs properties to a percent-level precision and search for new physics processes. A high Precision Proton Spectrometer (PPS) has been taking data as a subsystem of the CMS experiment. It uses a timing detector in order to measure the time of flight (ToF) of the two forward protons produced in the interaction point in the CMS detector. Considering central exclusive production processes (pp->pXp), 10 ps time resolution detector would provide 2.1 mm spatial resolution on the vertex position and improve of a factor of about 25 the background pile up suppression.