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Hydraulic external pre-isolator system for LIGO

Wen, S. and Mittleman, R. and Mason, K. and Giaime, J. and Abbott, R. and Kern, J. and O'Reilly, B. and Bork, R. and Hammond, M. and Hardham, C. and Lantz, B. and Hua, W. and Coyne, D. and Traylor, G. and Overmier, H. and Evans, T. and Hanson, J. and Spjeld, O. and Macinnis, M. and Mailand, K. and Ottaway, D. and Sellers, D. and Carter, K. and Sarin, P. (2014) Hydraulic external pre-isolator system for LIGO. Classical and Quantum Gravity, 31 (23). Art. No. 235001. ISSN 0264-9381. doi:10.1088/0264-9381/31/23/235001.

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The hydraulic external pre-isolator (HEPI) is the first six degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGOʼs fifth science run, successfully cutting down the disturbance seen by LLOʼs suspended optics in the two most prominent seismic disturbance bands, the microseism (0.1–0.3 Hz) and the anthropogenic (1–3 Hz) bands, by a factor of a few to tens. The improvement in seismic isolation contributed directly to LLOʼs much improved duty cycle of 66.7% and LIGOʼs triple coincident duty cycle of 53%. We report the design, control scheme, and isolation performance of HEPI at LLO in this paper. Aided by this success, funding for incorporating HEPI into the LIGO Hanford Observatory was approved and installation is currently underway.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Coyne, D.0000-0002-6427-3222
Ottaway, D.0000-0001-6794-1591
Additional Information:© 2014 IOP Publishing Ltd. Received 30 April 2014, revised 14 August 2014. Accepted for publication 26 August 2014. Published 13 November 2014. The authors acknowledge financial support from the National Science Foundation through grants PHY-0071316, 0107417, 0140297, 0304924, and 9801158, as well as the Louisiana Board of Regents contract LEQSF(2000–03)-RD-A-06.
Funding AgencyGrant Number
Louisiana Board of RegentsLEQSF(2000–03)-RD-A-06
Subject Keywords:gravitational wave detectors and experiments, applied fluid mechanics, structural acoustics and vibration
Issue or Number:23
Classification Code:PACS: 04.80.Nm, 95.55.Ym, 07.60.Ly. MSC: 83C
Record Number:CaltechAUTHORS:20150106-100448346
Persistent URL:
Official Citation:Hydraulic external pre-isolator system for LIGO S Wen et al 2014 Class. Quantum Grav. 31 235001
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:53203
Deposited By: Ruth Sustaita
Deposited On:06 Jan 2015 19:07
Last Modified:10 Nov 2021 19:49

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