STREGA

C2:Cryogenic suspension system for advanced resonant detectors (5 MIN)

Task -C2: development and construction of advanced cryogenic system for resonant detectors;

The double task of removing the heat from the antenna resonator while keeping it mechanically isolated from the environment is similar to the one that will be encountered in the cooling of the interferometer mirrors. Although the ultra cryogenic detectors have been successfully operated, further advances in cooling and/or isolating the antenna can be achieved via finite element modelling and experimental tests. Objective:- Two 1.2 ton spheres with their cryogenic suspension assembled and measurements of mechanical quality factor and thermal noise at low temperatures performed.

Participants:

INFN* - Istituto Nazionale di Fisica Nucleare MiniGRAIL - Leiden University – LION Institute of Physics

* Involved labs: Ferrara, Firenze, Genova, Frascati, Legnaro, Napoli, Padova, Perugia, Pisa, Roma 1, Roma 2, Trento, Urbino

STREGA

C2:Cryogenic suspension system for advanced resonant detectors (5 MIN)

STREGA

C2:Cryogenic suspension system for advanced resonant detectors (5 MIN)

Cooling MiniGRAIL

78 mK after 37 days. Heat leak of about 50 microW-Hydrogen? Internal stresses?

STREGA MiniGRAIL

Material CuAl6%

Diameter = 0.65 m

Mass M = 1150 kg

Resonant freq. f = 3160 Hz

Goal temperature ~ 20 mK

Expected sensitivity h~10-20

STREGA Vibration Isolation System

STREGA Vibration Isolation System

STREGA Vibration Isolation System

30 dB around 3 kHz

70 dB around 3 kHz

STREGA Vibration Isolation System

STREGA Vibration Isolation System

STREGA Vibration Isolation System

STREGA Vibration Isolation System

STREGA

To 50 mK shield

To mixing chamber

CryogenicsThermal anchoring suspension

To still shield

STREGACryogenicsThermal anchoring suspension

STREGA

C2:Cryogenic suspension system for advanced resonant detectors (5 MIN)