Reducing suspension control noise with interferometric sensors -- an experimental concept

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Weickhardt, Nils Leander, Basalaev, Artem, Gerberding, Oliver
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866908625162731520
author Weickhardt, Nils Leander
Basalaev, Artem
Gerberding, Oliver
author_facet Weickhardt, Nils Leander
Basalaev, Artem
Gerberding, Oliver
contents One of the limiting noise sources of ground-based gravitational wave detectors at frequencies below 30 Hz is control-induced displacement noise. Compact laser interferometric sensors are a prime candidate for improved local displacement sensing. In this paper we present the design of an experiment that aims to demonstrate the advantages of interferometric sensors over shadow sensors. We focus on the compact balanced readout interferometer (COBRI) - a sensor currently in development that is based on deep frequency modulation. We mount COBRIs on two HAM Relay Triple Suspension (HRTS) systems that suspend two mirrors forming an optical cavity. By measuring the length stability of this cavity relative to a stable reference we aim to probe the direct motion reduction when using COBRIs for active damping and we aim to investigate their behavior and auxiliary functions, such as absolute ranging, in the context of the 6 degree-of-freedom controls of the suspensions. Here we describe the design of the experiment and simulations of the achievable noise levels that were obtained using mechanical models of the HRTS suspensions. We discuss all relevant noise sources, the modeled influence of the interferometric sensor damping and the current limitations and necessary improvements of our testing facility in terms of seismic pre-isolation to achieve a shadow sensor limited noise at around 5 Hz, where, according to our simulations, we can demonstrate superior performance for COBRIs in the longitudinal degree of freedom.
format Preprint
id arxiv_https___arxiv_org_abs_2507_18369
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Reducing suspension control noise with interferometric sensors -- an experimental concept
Weickhardt, Nils Leander
Basalaev, Artem
Gerberding, Oliver
Instrumentation and Detectors
One of the limiting noise sources of ground-based gravitational wave detectors at frequencies below 30 Hz is control-induced displacement noise. Compact laser interferometric sensors are a prime candidate for improved local displacement sensing. In this paper we present the design of an experiment that aims to demonstrate the advantages of interferometric sensors over shadow sensors. We focus on the compact balanced readout interferometer (COBRI) - a sensor currently in development that is based on deep frequency modulation. We mount COBRIs on two HAM Relay Triple Suspension (HRTS) systems that suspend two mirrors forming an optical cavity. By measuring the length stability of this cavity relative to a stable reference we aim to probe the direct motion reduction when using COBRIs for active damping and we aim to investigate their behavior and auxiliary functions, such as absolute ranging, in the context of the 6 degree-of-freedom controls of the suspensions. Here we describe the design of the experiment and simulations of the achievable noise levels that were obtained using mechanical models of the HRTS suspensions. We discuss all relevant noise sources, the modeled influence of the interferometric sensor damping and the current limitations and necessary improvements of our testing facility in terms of seismic pre-isolation to achieve a shadow sensor limited noise at around 5 Hz, where, according to our simulations, we can demonstrate superior performance for COBRIs in the longitudinal degree of freedom.
title Reducing suspension control noise with interferometric sensors -- an experimental concept
topic Instrumentation and Detectors
url https://arxiv.org/abs/2507.18369