Disclaimer: The information provided on this website is authored solely by me, Nicolò Salimbeni, and represents my personal insights and contributions to the projects discussed. This content is not intended to serve as an official record or representation of the work or views of any other individuals or collaborators involved. Where applicable, I alone am responsible for the interpretations and descriptions provided here, which do not reflect any formal endorsement or validation by the teams or institutions associated with these projects.
Table of Contents
- CMS Detector Note on Outer Tracker PS Modules
- Measurement of the Muon Gyromagnetic Factor
- Fermilab Summer School Report
- Bachelor’s Thesis: Measurements of b-meson Oscillations with the CMS Detector
CMS Detector Note on Outer Tracker PS Modules
Following a summer school at Fermilab (FNAL), I was given the opportunity to contribute to the analysis of a test beam conducted in 2023. I joined the Outer Tracker group at Fermilab for three months, collaborating with them to co-author the associated detector note. The document is available here (restricted to authorized users). We are currently working on a collaboration paper based on this research, which will be publicly accessible once published.
Abstract (not official and not approved yet, provided here just for context):
The Large Hadron Collider (LHC) at CERN will undergo major upgrades to increase the instantaneous luminosity up to $ 5 - 7.5 \times 10^{34} \text{cm}^{-2} \text{s}^{-1} $. This High Luminosity upgrade of the LHC (HL-LHC) will deliver a total of $ 3000 - 4000$ $\text{fb}^{-1} $ of proton-proton collisions at a center-of-mass energy of 14 TeV. To cope with these challenging environmental conditions, the outer tracker of the CMS experiment will be upgraded using modules with two closely-spaced silicon sensors to provide tracking information for inclusion in the Level-1 trigger selection. This paper describes the performance, in a test beam experiment, of a PS (pixel-strip) module irradiated with protons. Only a section of the module was irradiated to allow a performance comparison with the non-irradiated side. Results demonstrate that the PS module meets the requirements, providing efficient tracking information even after being irradiated with a total fluence exceeding the expected lifetime exposure of the experiment.
Measurement of the Muon Gyromagnetic Factor
This report was prepared for the “Advanced Physics Laboratory” course at the University of Padua. The goal of the course was to design and conduct a particle physics experiment over the course of a year, covering all stages from setting up the data acquisition (DAQ) system to analyzing the results. Together with another student and with guidance from a professor, I worked on measuring the gyromagnetic factor of cosmic muons. The experiment utilized three scintillators, silicon photomultipliers (SiPMs), and a solenoid.
Fermilab Summer School Report
This report is the outcome of a summer school I attended at Fermilab in 2023. Through this project, I had the opportunity to join the CMS Outer Tracker group at FNAL, where I collaborated on the detector note referenced above.
Abstract: The Large Hadron Collider (LHC) will be upgraded to increase the instantaneous luminosity up to $5−7.5 \times 10^{34} \text{cm}^{−2} \text{s}^{−1}$. To face these challenging conditions the CMS tracking system must be updated, using modules that on the one hand are able to cope with high radiations and on the other hand can provide information to the L-1 trigger selection. This report describes the results of some tests on the new tracking modules at the FNAL test beam facility. In particular half of one module was irradiated by 400 MeV protons (total fluence comparable to the one expected through the lifetime of the experiment) and then some analysis were performed on both the irradiated and not irradiated side of the detector with a 120 GeV proton beam. In this report, the efficiency and noise occupancy analysis are presented, with focus on the main critical issues encountered.
Bachelor’s Thesis: Measurements of b-meson Oscillations with the CMS Detector
Abstract: In proton-proton (pp) collisions at the Large Hadron Collider, various hadrons are produced, including neutral B mesons, which can transform into their antiparticles (flavor oscillation). CMS aims to measure this phenomenon through the decay $ B \rightarrow D$ $\mu$ $\nu$, where the B can be either a $ B^0 $ or a $B_s$, and accordingly, the D can be a $ D^+ $ or a $ D_s^+ $. In this process, information is lost due to the neutrino, which cannot be detected, making it challenging to reconstruct the four-momentum of the initial B meson. The purpose of this thesis is to explore methods to reconstruct this four-momentum and to validate the approach using samples of fully reconstructed B mesons.
link: the thesis is public and can be downloaded here, but unfortunately my bachelor was in Italian, so the PDF is in Italian too.