\”Quasi-complete\” mechanical model for a double torsion pendulum
Authors: De Marchi F., Pucacco G., Bassan M., De Rosa R., Di Fiore L., Garufi F., Grado A., Marconi L., Stanga R., Stolzi F., Visco M.
Autors Affiliation: Dipartimento di Fisica, Università di Roma Tor Vergata and INFN Sezione Roma2, I-00133 Roma, Italy; Dipartimento di Fisica Ed Astronomia, Università Degli Studi di Firenze and INFN Sezione di Firenze, I-50019 Firenze, Italy; Istituto di Astrofisica e Planetologia Spaziali-INAF, Roma and INFN Sezione Roma2, I-00133 Roma, Italy; INFN Sezione di Napoli, I-80126 Napoli, Italy; Dipartimento di Fisica, Università Degli Studi di Napoli Federico II, I-80126 Napoli, Italy; Osservatorio Astronomico di Capodimonte-INAF, I-80126 Napoli, Italy
Abstract: We present a dynamical model for the double torsion pendulum nicknamed \”PETER,\” where one torsion pendulum hangs in cascade, but off axis, from the other. The dynamics of interest in these devices lies around the torsional resonance, that is at very low frequencies (mHz). However, we find that, in order to properly describe the forced motion of the pendulums, also other modes must be considered, namely swinging and bouncing oscillations of the two suspended masses, that resonate at higher frequencies (Hz). Although the system has obviously 6+6 degrees of freedom, we find that 8 are sufficient for an accurate description of the observed motion. This model produces reliable estimates of the response to generic external disturbances and actuating forces or torques. In particular, we compute the effect of seismic floor motion (\”tilt\” noise) on the low frequency part of the signal spectra and show that it properly accounts for most of the measured low frequency noise.
Journal/Review: PHYSICAL REVIEW D
Volume: 87 (12) Pages from: 122006-1 to: 122006-11
KeyWords: LISA (observatory); Gravity waves; Wave detectionDOI: 10.1103/PhysRevD.87.122006Citations: 7data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2022-01-23References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here