Search and characterization of pulsars in southern globular clusters: new methodologies and results from an S-band survey

This thesis explores the search for radio pulsars in globular clusters and the development of computational methods to enhance their detection under challenging observational conditions. Pulsars are rapidly rotating neutron stars---remnants of supernova explosions---and represent some of the most extreme objects in the Universe. Their study provides insight into ultra-dense matter, strong magnetic fields, and relativistic gravity. Beyond their intrinsic interest, pulsars serve as powerful tools for precision astrophysics. Their stable emission enables tests of fundamental physics, studies of stellar evolution, and probes of the interstellar medium and Galactic structure. Globular clusters are particularly rich environments for pulsar studies. These dense stellar systems promote frequent dynamical interactions, leading to the formation of exotic systems such as millisecond pulsars in binaries. These populations offer a unique perspective on stellar evolution in conditions distinct from the Galactic field. Detecting pulsars in globular clusters is, however, challenging. Interstellar propagation effects distort radio signals, while orbital motion in binary systems can smear periodic signatures, reducing detectability. These effects are especially severe for compact and rapidly evolving systems, requiring advanced observational strategies and analysis techniques. This thesis addresses these challenges through both observational and methodological approaches. Chapter~1 introduces the properties of neutron stars and pulsars. Chapter~2 focuses on pulsars in globular clusters and their dynamical formation. Chapter~3 presents the techniques used in radio pulsar searches. Chapter~4 describes the first MeerKAT S-band globular cluster survey, including its observational strategy and data analysis. Chapter~5 introduces a GPU-based time-domain search method designed to improve sensitivity to systems affected by complex orbital motion. Appendices provide additional technical details, including flux density estimation and observational considerations. Overall, this work aims to improve the detection and study of pulsars in dense stellar environments, contributing to our understanding of fundamental physics and stellar evolution under extreme conditions.