Conveners
Cryogenics for LF
- Takafumi Ushiba (ICRR)
- Ettore Majorana ()
Cooling mirrors and their suspensions are promising way to reduce thermal noise. To maximize the benefits of cooling, utilizing low mechanical loss material at cryogenic temperature is essential; therefore, KAGRA mirrors and their suspension fibers are made of sapphire. To achieve good cryogenic suspension, there are several technical difficulties because the suspension needs not only low...
The design of cryogenic suspensions for mass tests for future generation GW detectors is based on the balancing of several factors: mechanical properties, thermal conductivity, resonance frequencies, thermo-mechanical stress and generally any parameter that aims to reduce thermal noise of test masses. The talk will present the state of the art of studying the mechanical and thermal properties...
In the design of the cryogenic payload, thermal and mechanical FEA models are used for optimizing the system both for its structural and thermal behavior. The thermal study is important to have the temperature distribution along the suspension wires and the thermal resistances of to the various interconnections between the parts of the suspension. The mechanical study gives the estimation of...
The Einstein Telescope will increase the sensitivity to gravitational wave detections with respect to the current detectors, especially in the low-frequency band (down to 2 Hz). Reaching such sensitivities at low frequencies implies great technology challenges: in order to reduce the seismic and the thermal noise very soft suspensions and cryogenic temperatures are needed. A big challenge...
The institutes iLM and iP2i in Lyon are involved on a significant effort to develop the sapphire technology for the future cryogenic detectors. iLM is taking care of the crystalline growth of ultra-low level of optical absorption and mechanical losses of mirror substrates and last stage suspensions. iP2i through the platform LMA develops the ultra-low level of total optical losses of mirrors,...
A crucial milestone was recently completed in the IGR in the form of the
first silicon suspension hanging on Hydroxide catalysis bonds and
surviving cooling to cryogenics temperatures. Although the prototype
allowed to validate multiple engineering concepts, it is expected that
HCB won't meet the thermal noise requirements for the 3rd generation of
gravitational waves detectors. For...
Abstract. The low-frequency interferometer in the Einstein Telescope (ET-LF) shall be operated at test mass temperatures of 10 K to 20 K. Motivated by the potential of using superfluid helium (He-II) for cooling the test masses due to its exceptional heat transport properties and presumably low dissipative behaviour, we present the concept of integrating a double-walled He-II filled marionette...
