Analysis of the resonant modes present in a novel cryogenic test-mass suspension for the Einstein Telescope Gravitational Wave Observatory

File(s)
ET-0045A-25.pdf (2.3 MB)
Document type Technical report
Abstract This technical report expands on a broader analysis of a novel cryogenic suspension designed for third-generation gravitational-wave detectors. Specifically, it investigates the effects of geometric modifications to two key components that this system incorporates: a suspension beam and flexures operating under tension and compression, respectively. Using Finite Element Method (FEM) simulations in COMSOL and ANSYS, this study examines how variations in beam thickness and flexure aspect ratios influence the system’s natural resonant modes and some of its mechanical behavior. By systematically exploring these parameters, we identify configurations that minimize undesirable mechanical conditions and provide a basis for future studies, such as the flexure design from group 1 discussed in Section 3. Additionally, we analyze how beam thickness variations influence vibrational attenuation, aiming to extend the effective attenuation range by increasing the frequency of the second resonant mode, discussed in Section 4. Finally, we identify regions of high resonance amplitudes as potential sites for implementing active damping and cooling strategies, discussed in Section 5.
Author(s) Nelson Luis Leon,Leonardo González López
Code ET-0045A-25
Code issue time/date 18:02, Wednesday the 19th of February, 2025
Referral URL https://apps.et-gw.eu/tds/ql/?c=17772
 COPIED 
Series Projects ET ISB DIV 1 - Suspensions WP1.4 - Test-Mass Suspensions
Annex files