Broadband Quantum Noise Reduction in Advanced Virgo Plus: From Frequency-Dependent Squeezing Implementation to Detection Losses and Stray Light Mitigation

This book presents the first implementation of frequency-dependent squeezing in the Virgo gravitational wave detector, a technique that reduces quantum noise across the entire detection band. By lowering noise, it enhances Virgo’s ability to observe the universe.

It provides a detailed account of the experimental optical system—spanning hundreds of meters—and the measurement campaign that led to the first observation of frequency-dependent squeezing, with ellipse rotation occurring at the ta...