Work

Residual amplitude modulation in interferometric gravitational wave detectors

Year: 2013

Type: article

Abstract: The effects of residual amplitude modulation (RAM) in laser interferometers using heterodyne sensing can be substantial and difficult to mitigate. In this work, we analyze the effects of RAM on a complex laser interferometer used for gravitational wave detection. The RAM introduces unwanted offsets in the cavity length signals and thereby shifts the operating point of the optical cavities from the nominal point via feedback control. This shift causes variations in the sensing matrix, and leads to degradation in the performance of the precision noise subtraction scheme of the multiple-degree-of-freedom control system. In addition, such detuned optical cavities produce an optomechanical spring, which also perturbs the sensing matrix. We use our simulations to derive requirements on RAM for the Advanced LIGO (aLIGO) detectors, and show that the RAM expected in aLIGO will not limit its sensitivity.

Source: Journal of the Optical Society of America A

DOI: 10.1364/josaa.31.000081

Authors: Keiko Kokeyama, Kiwamu Izumi, William Z. Korth, Nicolas Smith-Lefebvre, Koji Arai, Rana X. Adhikari

Institutions: Louisiana State University, The University of Tokyo, California Institute of Technology

Language: English

Topic: Pulsars and Gravitational Waves Research

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funder: National Science Foundation

Awards: Gravitational Wave Detection and Astrophysics, Instrument Development and Data Analysis in LIGO, Instrument Development and Data Analysis for LIGO