The lower limit in sensitivity of gravitational wave detectors at their most sensitive frequencies arises from the Brownian motion of high reflectivity coatings on the test mass optics. In the aim to find alternative materials for the next upgrade of interferometric detectors, large interest was represented by Titania-doped Silica.
We present here our investigations into the mechanical and...
In addition to the fundamental noises (quantum noise, thermal noise, and seismic noise) affecting the sensitivity of ground-based gravitational-wave interferometers, the technical noises often limit some frequency bands. A substantial part of the detector commissioning is devoted to the study and the mitigation of technical noises. Scattered light is among these noises. In this presentation,...
In April 2021, a new instrumented baffle was installed surrounding the suspended end mirror of the Virgo’s Input Mode Cleaner (IMC) cavity, as part of the phase I upgrade of the Advanced Virgo interferometer. The device is equipped with photo sensors that monitor the stray light inside the cavity. It serves as a demonstrator of the technology for the baffles that will monitor the stray light...
The LIGO Scientific, Virgo and KAGRA Collaborations recently released the third gravitational-wave transient catalog or GWTC-3, significantly expanding the number of gravitational wave (GW) signals. There are various models proposed to describe the underlying mass distribution of these compact objects using computational extensive Bayesian hierarchical models and use them to predict the...
Wavefront sensing allows for probing mode mismatch, higher order modes and thermal effects in gravitational-wave interferometers, all of which need to be well controlled as they impact the interferometer’s stability and sensitivity. The phase cameras installed at Advanced Virgo (AdV) are capable of generating amplitude and phase images of the laser beam wavefront at any beat frequency of...
The increase of the optical power expected for the new observing run (O4) will lead to an improvement of the interferometer (ITF) sensitivity with a consequently increase of the detection volume and the number of candidate sources. At this condition, the thermal distortions, induced by absorption inside the optics, degrade the ITF performance reducing the quality of the control signals and the...
On 14 September 2015, a century after the birth of General Relativity, all the scientific and technological efforts for the experimental detection of gravitational waves (GWs) found a reward. The instruments that allowed the first direct detection are second-generation GW interferometers, such as LIGO and Virgo. At present, after the conclusion of the scientific observing run O3, about 90 GW...
