In experimental particle physics, large detectors are crucial for identifying subatomic particles. Central to these detectors are pixel sensors, which require radiation tolerance and resolution enhancements for the upcoming High-Luminosity Large Hadron Collider (HL-LHC) upgrade. This has prompted the development of next generation monolithic pixel sensors (namely, MALTA and MALTA2), monolithic active pixel sensors engineered using the 180 nm TowerJazz CMOS technology. Before deployment, conducting a comprehensive characterization of these sensors is imperative. Fast timing is a characteristic required for monolithic pixel detectors. However, this is difficult to measure directly with conventional Laser techniques due to the metal layers of the sensor that reflect the Laser. To overcome this, X-rays are employed for their ability to penetrate these layers. The specialized triggered X-ray setup is designed for precise timing measurements of monolithic detectors, which utilize a micro X-ray source, emitting short pulses from a Cu-Cr target synchronized with an input trigger source. The MALTA2 Pixel detector's timing response is meticulously assessed and compared with the timing metrics of the setup, ensuring accurate characterization and readiness for future high-precision particle detection tasks.



The strong CP problem marks a potential issue in the Standard Model and can be addressed with the Peccei-Quinn mechanism. The breaking of the Peccei-Quinn symmetry would dynamically suppress the CP-violating term in QCD, thereby resolving the strong CP problem and leading to a new particle: the axion. One way to detect axions experimentally is from light-by-light scattering (\gamma+\gamma \rightarrow \gamma+\gamma) in a high magnetic field, which is possible in ultra-peripheral lead-lead collisions in the CMS detector. A theoretical background with previous results has been summarised, and a study is proposed for using Run-3 data from the CMS experiment.