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Title: A cryogenic torsion balance using a liquid-cryogen free, ultra-low vibration cryostat
We describe a liquid-cryogen free cryostat with ultra-low vibration levels, which allows for continuous operation of a torsion balance at cryogenic temperatures. The apparatus uses a commercially available two-stage pulse-tube cooler and passive vibration isolation. The torsion balance exhibits torque noise levels lower than room temperature thermal noise by a factor of about four in the frequency range of 3–10 mHz, limited by residual seismic motion and by radiative heating of the pendulum body. In addition to lowering thermal noise below room-temperature limits, the low-temperature environment enables novel torsion balance experiments. Currently, the maximum duration of a continuous measurement run is limited by accumulation of cryogenic surface contamination on the optical elements inside the cryostat.  more » « less
Award ID(s):
1912380
NSF-PAR ID:
10339931
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Review of Scientific Instruments
Volume:
93
Issue:
6
ISSN:
0034-6748
Page Range / eLocation ID:
064505
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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