Achieving resonance in the Advanced LIGO gravitational-wave interferometer
Author(s)
Staley, A.
Martynov, D.
Abbott, R.
Adhikari, R. X.
Arai, K.
Ballmer, S.
Barsotti, Lisa
Brooks, A. F.
DeRosa, R. T.
Dwyer, S.
Date Issued
November 2014
Journal
Classical and Quantum Gravity
Publisher
IOP Publishing
Citation
Staley, A. et al. “Achieving Resonance in the Advanced LIGO Gravitational-Wave Interferometer.” Classical and Quantum Gravity 31, 24 (November 2014): 245010 © IOP Publishing Ltd
Version
Original manuscript
Abstract
Interferometric gravitational-wave detectors are complex instruments comprised of a Michelson interferometer enhanced by multiple coupled cavities. Active feedback control is required to operate these instruments and keep the cavities locked on resonance. The optical response is highly nonlinear until a good operating point is reached. The linear operating range is between 0.01% and 1% of a fringe for each degree of freedom. The resonance lock has to be achieved in all five degrees of freedom simultaneously, making the acquisition difficult. Furthermore, the cavity linewidth seen by the laser is only ~1 Hz, which is four orders of magnitude smaller than the linewidth of the free running laser. The arm length stabilization system is a new technique used for arm cavity locking in Advanced LIGO. Together with a modulation technique utilizing third harmonics to lock the central Michelson interferometer, the Advanced LIGO detector has been successfully locked and brought to an operating point where detecting gravitational-waves becomes feasible.
MIT Department
Massachusetts Institute of Technology. Department of Physics
LIGO (Observatory : Massachusetts Institute of Technology)
MIT Kavli Institute for Astrophysics and Space Research
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1088/0264-9381/31/24/245010
