Carole Perigois – Phd’s defense – oct. 4, 2021
Advanced Virgo background noise study and research of astrophysical stochastic gravitational background.
Virgo is an enhanced Michelson interferometer in Cascina, Italy. Its aim is to detect gravitationnal waves from atrophysical phenomena such as binary coalescences. At present the detector is in maintenance phase. Upgrade and commisioning are in progress to prepare its third run that will begin in February 2019. The gravitational stochastic background is defined by the superposition of every non-resolved sources due to instrumental noise. This projet has two objectives: understand instrument noise sources and analyse the data to find the stochastic background. To start the run it is necessary to understand well the detector instrumental noises. This reasearch projet will begin by a detector study for understanding its limits in the third run, and will follow with a study of noises due to new upgrades for the fourth run in february 2021. The second part of the work is to develop a new optimised analysis method to detect the gravitational stochastic background. First analysing simulated data and then applying it to real data from the third observing run