Correlated charm pairs at the LHCb Experiment

The Standard Model of particle physics has proven to be one of the most successful theories in modern physics, providing an excellent description of electromagnetism and the strong and weak interactions. Yet, it still leaves many questions unanswered, such as the apparent matter-antimatter asymmetry in the universe. For this asymmetry to occur, both C (charge conjugation) and P (parity) symmetries must be violated in the interaction of fundamental particles.
While the Standard Model allows CP violation to occur, it fails to fully account for the matter-antimatter imbalance on a cosmological scale, necessitating the developement of physics beyond the Standard Model. To this end, the main goals of flavour physics include searching for new sources of CP violation, and performing precise measurements of Standard Model parameters using decays of heavy flavour (containing b or c quarks) particles.
A particularly promising phenomenon in the area of charm physics is the decay of particles with definite C and P eigenvalues into correlated DoDo pairs. The correlations in the DoDo system enable the direct measurement of T (time-reversal) symmetry in the system. As CP violation has been observed in the charm system, a direct measurement of T symmetry would allow for a test of CPT symmetry, which, if broken, would clearly point to physics beyond the Standard Model. Moreover, such correlated charm pairs could reduce systematic uncertainties on amplitude analyses of B meson decays by constraining the possible resonances. This in turn could enable us to better study the properties of new types of hadrons, such as exotic mesons and tetraquarks.
The LHCb experiment is one of the four major detectors at CERN, optimised for the study of heavy flavour particles. The unique capabilities of the detector provide an excellent platform with which to search for new physics using correlated charmed hadrons. Using samples of decays collected during runs 2 and 3 of the LHCb experiment, I will attempt to reconstruct DoDo systems in a C=+1 eigenstate and extract the corresponding lineshape in the DoDo invariant mass spectrum. This allows the yields of DoDo pairs in their CP eigenstates to be determined in subsequent analyses, and is an instrumental step in measuring T violation in correlated charm systems. Eventually, these same charm systems can also provide key constraints on CP violation in the beauty system. Additionally, I will also perform a feasibility study to quantify the effects of including correlated charm pairs in amplitude analyses using a Monte-Carlo simulated sample of decays.