Speaker
Description
The ETpathfinder is a cryogenic test facility in Maastricht, aimed at developing core technologies for the Einstein Telescope. The facility utilises a high-sensitivity ($<1\cdot 10^{-18}$ m/Hz at 10 Hz), 10-meter interferometer to evaluate crucial subsystems. A crucial aspect is the performance of crystalline silicon test masses and their suspensions under extreme cryogenic operating conditions, specifically targeting for temperatures around 18 K and 123 K. Due to its high mechanical quality factor and high thermal conductivity at cryogenic temperatures, Silicon is a strong candidate for use in suspension elements. To address potential variations in the geometry of Silicon suspension wires and further minimise thermal noise, the implementation of silicon blade springs is being explored. Given its low coefficient of thermal expansion, interfaces between the crystalline suspension and metal components are challenging. This poster presents the cryogenic setup for thermal conductivity measurements of the Silicon blades and their clamping system from 10 K to 300 K. Additionally, different clamp designs are being discussed.