Published October 31, 2014 | Version Published
Book Section - Chapter Open

Coming clean: understanding and mitigating optical contamination and laser induced damage in advanced LIGO

  • 1. ROR icon California Institute of Technology

Abstract

The cleanliness of optical surfaces is of great concern as the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) project transitions from installation to operation at full power. More particulates than expected were observed on and near the core optics as a result of assembly and installation work, prompting a re-evaluation of longheld contamination control practices. Even low particulate levels can potentially damage the fused silica optics and reduce overall interferometer sensitivity. These risks are mitigated from a combination of the following approaches: quantifying the extent of the contamination, identifying its sources, improving practices to reduce the generation of particulates, introducing a non-contact in-situ cleaning technique for suspended optics in air, qualifying cleanliness levels against induced damage, and developing methods for remotely measuring and cleaning suspended optics under vacuum. While significant progress has been made in understanding and mitigating contamination, and thus, protecting the optics from losses and damage, there is still more work to be done to reach ultimate performance requirements.

Additional Information

© 2014 SPIE. The authors gratefully acknowledge the support of the United States National Science Foundation (award No. PHY-0757058). LIGO was constructed by the California Institute of Technology and Massachusetts Institute of Technology with funding from the National Science Foundation, and operates under cooperative agreement PHY-0107417. Caltech also acknowledges financial support from the Science and Technology Facilities Council of the United Kingdom. This paper filed internally under LIGO document number LIGO- P1400205. LIGO Internal Reports may be accessed at https://dcc.ligo.org/cgi-bin/DocDB/DocumentDatabase. The authors wish to acknowledge the many colleagues in LIGO and the LIGO Scientific Collaboration who have supported this work. In particular, the authors would like to thank Jeff Bartlett, Garilynn Billingsley, Dennis Coyne, Eric Gustafson, Matthew Heintze, Norna Robertson, Betsy Weaver and Liyuan Zhang within LIGO. In addition, the authors would like to thank all of the excellent contacts they now have within the National Ignition Facility.

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Additional details

Identifiers

Eprint ID
55699
Resolver ID
CaltechAUTHORS:20150311-104401320

Funding

NSF
PHY-0757058
NSF
PHY-0107417
Science and Technology Facilities Council (STFC)

Dates

Created
2015-03-11
Created from EPrint's datestamp field
Updated
2021-11-10
Created from EPrint's last_modified field

Caltech Custom Metadata

Series Name
Proceedings of SPIE
Series Volume or Issue Number
9237
Other Numbering System Name
LIGO Document Number
Other Numbering System Identifier
LIGO-P1400205