1. 7-14-06 RLSCamera Cooling1 Camera Cooling Discussion Richard L. Schmitt Fermilab July 14, 2006

2. 7-14-06 RLSCamera Cooling2 Cryo Coolers or Liquid Nitrogen?

3. 7-14-06 RLSCamera Cooling3 Heat Load Focal Plate Supports: 10 Watts CCD’s: 20 Watts Wiring and Cables: 25 Watts Radiative heat load: 70 Watts Add safety factor Total heat load: 200 Watts

4. 7-14-06 RLSCamera Cooling4 Location of Cryo Coolers

5. 7-14-06 RLSCamera Cooling5 Cryo Cooler Types Cryo- Cooler System Type # of units required Orientation DependantVibration Operating temperature Operational Considerations Cryo-Tiger (JT)9No No moving parts; No pressure pulsation120 K Note negative APO experience; Several units required CryoMech (PT)4Yes+/- 1 lbf @ 1.4 Hz 77 K in vertical position Multiple units required; Performance dependant on orientation CryoMech (GM01No +/- 50 lbf @ 2.4 Hz77 K High vibration level

6. 7-14-06 RLSCamera Cooling6 Vibration (sources) Cryocoolers used for CLIO, LEGT, CDMS –Vibration of Camera Caused by Cryo-Cooler, Zhijing Tang, August 10 2004. –Vibration Analysis of Cryocoolers, Tomaru, Takayuki, et al. 2004. –Current status of large-scale cryogenic gravitational wave telescope. K Kuroda, et al. August 18 2003 –Low-Noise Cooling of HT-SQUIDS by Means of a Pulse Tube Cooler with Additional Vibration Compensation. Lienerth, Thummes and Heiden. 2000. –Design and Construction status of CLIO. M Ohashi, et al. August 7 2003. –Vibration-Free Pulse Tube Cryocooler System for Gravitational Wave Detectors I. T Tomaru, et al. –Large-Scale Cryogenic Gravitational Wave Telescope. K Kuroda, et al. 1999.

7. 7-14-06 RLSCamera Cooling7 Vibration Isolation can reduce vibrations at detector to near seismic levels GM more vibration below 15 Hz than Pulse Tube Motions under 0.2 Mm- Per Z.T., 50 lb at 2.4 Hz CDMS Isolation –Support –Vacuum bellows –Braids –Wire bundles –GM vibration reduced by factor of 80

8. 7-14-06 RLSCamera Cooling8 CDMS Flat braid on first stage Vacuum bellows 0.2 inches motion along Estem axis 20,000 wires,.0005 inch diameter

9. 7-14-06 RLSCamera Cooling9 Cryocooler Costs TypeModel ReferencePower Consumption CapacityCost PTCryoMech PT603.0 kW60 W @ 77K$50 K JTIGC Polycold CryoTiger 0.5 kW3.5 W @ 77K$137 K GMCryoMech AL3007.2 kW300 W @ 77K$29 K

10. 7-14-06 RLSCamera Cooling10 Nitrogen Batch Filling

11. 7-14-06 RLSCamera Cooling11 Circulation