Hello again. Last time I wrote a newsletter was about a year ago where I was a new member of the GraWIToN project. The first time was about introducing myself, speaking about the project in a general manner since it was very new to me. But now it is possible to speak about something more specific after controlling all the different aspects of my research.

In fact, my research work is composed of two different parts with two different laboratories in two different countries. The first laboratory is at BOOSTEC company in collaboration with LGP INP/ENIT, that is an affiliation of the Federal University of Toulouse in France. In this Laboratory, I am working on the thermal and thermo-elastic behavior of silicon carbide (SiC) optical components under two different temperature conditions “room temperature” as in Advanced VIRGO and “cryogenic temperature” for the third generation gravitational wave detector “Einstein Telescope ET”.

Furthermore, the second laboratory is at EGO site in Italy where I am studying the optical behavior of SiC composed of optical characterization and optical simulation. The optical characterization and the optical simulation are performed also under the same temperature conditions to measure scattering and evaluate the intensity of this scattering respectively.

Now, after one year of understanding the subject, it is possible to set the methodology of the simulation work in this thesis which is the essential part for investigating the behavior of SiC baffles.

This methodology illustrates the links between all the experimentation and simulation works. So as a quick explanation, optical experiments allow us to characterize the material (SiC) and to identify the necessary parameters needed for the optical simulations. This allow us to evaluate the flux of the scattered light, which is used as an input in the thermal analysis to study the temperature variation and distribution on the baffles. Hence, after calculating the thermal field, it is introduced as an input to the thermo-elastic analysis to study the deformation of these baffles due to the thermal stress.

The preliminary results of this methodology showed that SiC is a very good candidate at both temperatures “room 293 K and cryogenic 70 K”, however, the investigation is still progressing towards lower temperatures such as 20 K.

Concerning the optical characterization, the preliminary results were only at room temperature and as a conclusion after comparing several samples of SiC and Stainless Steel 304, SiC-CVD has proved that it is the very promising material for our application. However, for the cryogenic temperature, an apparatus is still being discussed with all the necessary optical components needed and it will be ready for the second secondment that is six months starting from next October at EGO Italy.

Some preliminary results of the temperature variation on Stainless Steel 304 AR-coated baffles (AdV) and Silicon Carbide (SiC) for ET at two different temperature conditions (room and cryogenic temperatures). A poster also presented these results during the GWADW 2016 conference at Isle d’Elba in May 2016.

The detection of gravitational waves was a shocking and astonishing news to me at the same time. Despite the fact that my current research was not involved in this phenomenal moment. It gave me a huge boost of motivation to achieve the goals of my research for the ET and work on the constraints and challenges of the future gravitational wave detectors. I am so lucky to be a part of this ongoing field of research.

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