Achieving geodetic motion for LISA test masses: ground testing results.
The low-frequency resolution of space-based gravitational wave observatories such as LISA (Laser Interferometry Space Antenna) hinges on the orbital purity of a free-falling reference test mass inside a satellite shield. We present here a torsion pendulum study of the forces that will disturb an orbiting test mass inside a LISA capacitive position sensor. The pendulum, with a measured torque noise floor below 10 fN m/square root of Hz from 0.6 to 10 mHz, has allowed placement of an upper limit on sensor force noise contributions, measurement of the sensor electrostatic stiffness at the 5% level, and detection and compensation of stray dc electrostatic biases at the millivolt level.
Carbone
L
L
Dipartimento di Fisica, Università di Trento, and I.N.F.N., Gruppo di Trento, 38050 Povo (TN), Italy.
Cavalleri
A
A
Dolesi
R
R
Hoyle
C D
CD
Hueller
M
M
Vitale
S
S
Weber
W J
WJ