Related papers: Nonlinear vibration transfer in torsion pendulums
We describe a torsion pendulum with a large mass-quadrupole moment and a resonant frequency of 2.8 mHz, whose angle is measured using a modified Michelson interferometer. The system achieved noise levels of $\sim200\…
Detection of low frequency gravitational waves around 0.1 Hz is one of the important targets for future gravitational wave observation. One of the main sources of the expected signals is gravi- tational waves from binary intermediate-mass…
We discuss a new torsion pendulum design for ground testing of prototype LISA (Laser Interferometer Space Antenna) displacement sensors. This new design is directly sensitive to net forces and therefore provides a more representative test…
We report on the design and sensitivity of a new torsion pendulum for measuring the performance of ultra-precise inertial sensors and for the development of associated technologies for space-based gravitational wave observatories and…
A four mass torsion pendulum facility for testing of the LISA GRS is under development in Trento. With a LISA-like test mass suspended off-axis with respect to the pendulum fiber, the facility allows for a direct measurement of surface…
The torsion pendulum is a prevailing instrument for measuring small forces acting on a solid body or those between solid bodies. While it offers powerful advantages, the measurement precision suffers from thermal noises of the suspending…
Probing the possibility of entanglement generation through gravity offers a path to tackle the question of whether gravitational fields possess a quantum mechanical nature. A potential realization necessitates systems with low-frequency…
Recently, first limits on putative Lorentz invariance violation coefficients in the pure gravity sector were determined by the reanalysis of short-range gravity experiments. Such experiments search for new physics at sidereal frequencies.…
We explore a new class of chipscale torsion pendula formed by Si$_3$N$_4$ nanoribbon suspensions. Owing to their unique hierarchy of gravitational, tensile, and elastic stiffness, the devices exhibit damping rates of $\sim 10\;\mu$Hz and…
Precise measurements of the displacement of, and force acting on, a mechanical oscillator can be performed by coupling the oscillator to an optical cavity. Brownian thermal forces represent a fundamental limit to measurement sensitivity…
Measurement of mutual gravitation on laboratory scales is an outstanding challenge and a prerequisite to probing theories of quantum gravity. A leading technology in tabletop gravity experiments is the torsion balance, with limitations due…
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…
We have developed a torsion pendulum facility for LISA gravitational reference sensor ground testing that allows us to put significant upper limits on residual stray forces exerted by LISA-like position sensors on a representative test mass…
Measuring gravitational interactions on sub-100-$\mu$m length scales offers a window into physics beyond the Standard Model. However, short-range gravity experiments are limited by the ability to position sufficiently massive objects to…
We present a new differential mechanical gradiometer for the detection of low-frequency Gravitational Waves. The frequency range is 0.05 to 1 Hz, a frequency gap not covered either by future space-based detectors such as LISA or by…
A torsion pendulum allows ground-based investigation of the purity of free-fall for the LISA test masses inside their capacitive position sensor. This paper presents recent improvements in our torsion pendulum facility that have both…
Gravitational forces that oscillate at audio-band frequencies are measured with masses suspended as pendulums that have resonance frequencies even lower. If the pendulum is excited by thermal energy or by seismic motion of the environment,…
Superconducting gravimeters are the most sensitive instruments to measure surface gravity changes at low frequencies. Currently, about twenty five superconducting gravimeters are operating in the world and their global network has been…
The nearly-incessant free oscillations of the Earth (not the larger, long-lived normal modes seen following intense quakes) were first observed by accident in the record of a tilt-sensitive instrument designed to study surface physics.…
Using weak values amplification angular resolution limits, we theoretically investigate the gravitational sensing of objects. By inserting a force-sensing pendulum into a weak values interferometer, the optical response can sense…