Associated Production of W + Charm in 13 TeV Proton-Proton Collisions Measured with CMS and Determination of the Strange Quark Content of the Proton

The study measures W+c production in proton-proton collisions at 13 TeV using the Compact Muon Solenoid (CMS) experiment,which allows for the precise measurement of the strange quark content of the proton. The results are in good agreement with those obtained in neutrino scattering experiments and extend the kinematic reach of the analysis.

Format: Paperback / softback
Length: 148 pages
Publication date: 19 August 2021
Publisher: Springer Nature Switzerland AG

The sole mechanism in proton-proton collisions that directly investigates the strange quark composition of the proton is the concurrent production of a W boson and a single charm quark (W+c). In this thesis, the production of W+charm is measured in proton-proton collisions at the LHC at 13 TeV, as recorded by the Compact Muon Solenoid (CMS) experiment. The analysis primarily concentrates on identifying W bosons in their leptonic decay to a muon and a neutrino, while charm quarks are tagged through the full reconstruction of D*-Mesons. The measured cross sections of W+c production are utilized, in conjunction with other relevant CMS results and the most precise HERA DIS data, in a QCD analysis to determine the strange quark content of the proton. The resulting strange quark distribution and suppression, with respect to the other light sea quarks, are in excellent agreement with those obtained in neutrino scattering experiments and extend their kinematic reach.

The study of the strange quark content of the proton is a crucial endeavor in particle physics, as it provides insights into the fundamental structure of matter and the forces that govern it. The associated production of a W boson and a single charm quark (W+c) is a unique process in proton-proton collisions that allows for direct measurement of the strange quark content of the proton. In this thesis, the production of W+charm is measured in proton-proton collisions at the Large Hadron Collider (LHC) at a center-of-mass energy of 13 TeV, as recorded by the Compact Muon Solenoid (CMS) experiment.

The analysis focuses on the identification of W bosons in their leptonic decay to a muon and a neutrino, while charm quarks are tagged through the full reconstruction of D*-Mesons. The measured cross sections of W+c production are used, in combination with other relevant CMS results and the most precise HERA DIS data, in a QCD analysis to determine the strange quark content of the proton.

The resulting strange quark distribution and suppression, with respect to the other light sea quarks, are in excellent agreement with those obtained in neutrino scattering experiments and extend their kinematic reach. This agreement demonstrates the reliability and accuracy of the measurements and provides valuable insights into the strange quark content of the proton.

The study of W+charm production also sheds light on the dynamics and interactions of quarks and gluons in the proton. The production of W+charm involves the collision of two quarks, a charm quark and a gluon, which subsequently decay into a W boson and a charm quark. The analysis of the decay process provides information about the strength and nature of the gluon-charm interaction, which is an important component of the strong force that binds quarks together in protons and neutrons.

Furthermore, the study of W+charm production has implications for other areas of physics, such as cosmology and astrophysics. The production of W bosons in high-energy collisions is a significant source of cosmic rays, which are high-energy particles that originate from distant astrophysical sources. The study of W+charm production can help us understand the origin and composition of cosmic rays and their impact on the universe.

In conclusion, the study of W+charm production at the LHC provides a powerful tool for investigating the strange quark content of the proton and the dynamics and interactions of quarks and gluons in the proton. The measurements and analysis of W+charm production have significant implications for particle physics, cosmology, and astrophysics, and continue to be an active area of research.

Weight: 261g
Dimension: 235 x 155 (mm)
ISBN-13: 9783030527648
Edition number: 1st ed. 2020