Non-Linear Angular Noise Coupling into Differential Arm Length

Document #:

LIGO-T1700343-v1

Document type:

T - Technical notes

Abstract:

Mirror misalignments of the Fabry Perot Cavity mirrors can change the cavity length. This source of noise can couple into differential arm length of a gravitational wave detector. This paper explores length change due to angular misalignment, and then extends it to the effect of angular noise on the two cavity system. We will also provide results from an experiment where we use mechanical modulation to measure the main angular components that are believed to couple most strongly to the differential arm length. The angular noise coupling model and experimental results will be used in combination to understand the angular noise contribution to differential arm length noise.

Files in Document:

• Final Report (LIGOSURF_FinalReport_BrianSeymour.pdf, 3.1 MB)

Other Files:

• Final Presentation (BrianSeymour_FinalPresentation_LIGO_SURF.pdf, 3.0 MB)
• Interim Report #1 (Angular_Subtraction_LIGO_Interim1.pdf, 2.1 MB)
• Interim Report #2 (BrianSeymour_Interim2LIGOSURF.pdf, 2.2 MB)
• Original Project Proposal (BSeymour-angular-subtraction-ProjectProposal.pdf, 228.8 kB)
• Revised Project Proposal (BSeymour_Revised_Project_Proposal.pdf, 251.9 kB)

Topics:

• Sensing and Control

Authors:

• Brian Seymour
• Arnaud Pele
• Marie Kasprzack
• Adam Mullavey

Keywords:

SURF17 SURF2017 ASC A-A

Notes and Changes:

Brian Seymour SURF 2017, LLO.

Referenced by:

• LIGO-T1800048: Final reports from LIGO SURF program, Summer 2017