• Nessuna parola chiave trovata

A non Gaussian, Flat-Topped, laser beam profile, also called Mesa Beam Profile supported by non spherical mirrors known as Mexican Hat (MH) mirrors, has recently been proposed [1] as a way to depress the mirror thermal noise and thus improve the sensitivity of future interferometric Gravitation Wave detectors including Advanced LIGO [2]. Non-Gaussian beam configurations have never been tested. The main motivation of this project is to demonstrate the feasibility of this new concept. The topic of this thesis is to design and build a Fabry-Perot cavity which can support a Mesa beam. The construction of the MH mirrors for this cavity requires more time than available to me. This thesis represents the initial work necessary to design this type of resonator. The construction of a mechanical structure capable to support both a Gaussian or a mesa beam and the testing of the structure with standard spherical mirrors and Gaussian beams is also part of this thesis. The test of the Mesa beams properties will be covered in a different thesis work when the new mirrors will become available in the fall. The first part of this thesis presents the motivation to develop this project. The second part presents requirements, design and construction of the experimental apparatus necessary to test the MH beams. The third part will presents the initial configuration and the preliminary results of the tests with spherical optics in the Fabry-Perot cavity