Terahertz approaches for cultural heritage diagnostic analysis and real-time detection of environmental pollutants

This thesis investigates the principles, methodologies, and applications of ter ahertz (THz) spectroscopy, with a focus on Cultural Heritage science and en vironmental monitoring. The work begins by establishing the theoretical foun dations of THz spectroscopy, covering both continuous-wave and time-domain techniques, and detailing the experimental setups, measurement protocols, and data processing methods developed to enable precise material characterization. The application of THz spectroscopy to Cultural Heritage materials is ex plored through studies on the optical properties of materials commonly found in artworks and archaeological artifacts (i.e., natural and synthetic pigments and corrosion by-products), the non-invasive analysis of layered artworks to re veal hidden stratifications, and a multi-analytical case study examining pictorial materials in a XVI century book illustrated by Gherardo Cibo. In parallel, the thesis addresses environmental applications, demonstrating the potential of THz spectroscopy for real-time monitoring of gaseous pollutants. This includes the spectral characterization of atmospheric pollutants and the development of innovative experimental setups for in-field detection and remote sensing. Preliminary investigations into additional applications, such as security screen ing and food diagnostics, further illustrate the versatility of THz technology. Overall, this work bridges fundamental THz spectroscopy with practical ap plications, advancing non-invasive material analysis and environmental sensing and offering new directions for research and technological development in both domains.