Cryogenically Cooled Ultra Low Vibration Silicon Mirrors for GW Observatories

Document #:

LIGO-P1600301-v6

Document type:

P - Publications

Abstract:

Interferometric gravitational wave observatories recently launched a new field of gravitational wave astronomy with the first detections of gravitational waves in 2015. The number and quality of these detections is limited in part by thermally induced vibrations in the mirrors, which show up as noise in these interferometers. One way to reduce this thermally induced noise is to use low temperature mirrors made of high purity single-crystalline silicon. However, these low temperatures must be achieved without increasing the mechanical vibration of the mirror surface or the vibration of any surface within close proximity to the mirrors. The vibration of either surface can impose a noise inducing phase shift on the light within the interferometer or physically push the mirror through oscillating radiation pressure. This paper proposes a system for the Laser Interferometric Gravitational-wave Observatory (LIGO) to achieve the dual goals of low temperature and low vibration to reduce the thermally induced noise in silicon mirrors. Experimental results are obtained at Stanford University to prove that these dual goals can be realized simultaneously.

Files in Document:

• P1600301-v6 (P1600301-v6.pdf, 8.6 MB)

Topics:

• Basic R&D

Authors:

• Brett Shapiro
• Rana Adhikari
• Odylio Aguiar
• Edgard Bonilla
• Danyang Fan
• Litawn Gan
• Ian Gomez
• Sanditi Khandelwal
• Brian Lantz
• Timothy MacDonald
• Dakota Madden-Fong

Notes and Changes:

This paper has been accepted for publication in the journal Cryogenics.
http://www.journals.elsevier.com/cryogenics

https://doi.org/10.1016/j.cryogenics.2016.12.004

-v2: Minor modifications to the text.

-v3: Includes feedback from authors

-v4: Adds a reference for the CTE of Si. The stated Si CTE = 0 temperature was changed from 123 K to 124 K. 124 K is closer since it's more precisely 123.9 K. Added the Stanford NSF cooperative agreement number to the acknowledgements.

-v5: Updated based on comments from the P&P review, co-authors, and others. These updates include a title change. This is the version being submitted for publication.

-v6: Updated based on comments from the journal's reviewers, and reformatted using the journal's latex class. Modifications include at statement about the test mass's temperature tolerance and how it will be controlled, and more details in Fig's 2 and 4. This version was accepted for publication on 9 Dec 2016.

Referenced by:

• LIGO-G1700404-v3: LIGO Voyager Cryogenics at Stanford