1 / 20

Very brief update on the GEO mystery noise investigations

Very brief update on the GEO mystery noise investigations. Stefan Hild for the GEO600 team 15th ILIAS WG1 meeting, March 2008, Cascina. Photographs by A. Freise. Introduction. Just a quick update: following up the mystery noise session + brainstorming at last ILIAS meeting.

arlen
Download Presentation

Very brief update on the GEO mystery noise investigations

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Very brief update on the GEO mystery noise investigations Stefan Hild for the GEO600 team 15th ILIAS WG1 meeting, March 2008, Cascina

  2. Photographs by A. Freise Introduction • Just a quick update: following up the mystery noise session + brainstorming at last ILIAS meeting. • See:http://www.ego-gw.it/ILIAS-GW/WP1docs/hild_231007.pptfor further detail… ILIAS WG1, March 2008

  3. Mystery noise How to tackle the mystery noise ? ILIAS WG1, March 2008

  4. Mystery noise How to tackle the mystery noise ? Displacement noise Yes / No ? Characteristics of the mystery noise Any clues from the observation? Displacement-like or not? Stationary? Related to glitches? .... ILIAS WG1, March 2008

  5. Mystery noise How to tackle the mystery noise ? Fundamental noises Projected noises Displacement noise Yes / No ? Characteristics of the mystery noise Is the gap real? All projections correct? Are all noises projected? Calculations of fundamental noises correct? ILIAS WG1, March 2008

  6. Mystery noise How to tackle the mystery noise ? Upconversion Fundamental noises Scattered light Projected noises Exotic noises Displacement noise Yes / No ? Characteristics of the mystery noise Can we rule out the usual candidates: non-linearly coupling noises? How about exotic noises ? .... ILIAS WG1, March 2008

  7. ILIAS WG1, March 2008

  8. Low vs high power Nominal power low power The gap looks smaller at low power, but … ILIAS WG1, March 2008

  9. Low vs high power … but the mystery stays roughly the same ILIAS WG1, March 2008

  10. ILIAS WG1, March 2008

  11. ILIAS WG1, March 2008

  12. Is there any correlation at SR-tuning of 350 Hz ??? Slide from October presentation Frequency noise projection: A smoking gun ? The change of the mystery noise from 550Hz to 1kHz tuning looks suspiciously similar to the change of the frequency noise transfer function. ILIAS WG1, March 2008

  13. Mystery noise vs frequency-noise-TF • 550 Hz and 1kHz fit pretty well, but 350 Hz does not. • Could indicate that part of the noise is caused by frequency noise ILIAS WG1, March 2008

  14. Frequency noise • Part of the mystery noise was caused by frequency noise. • See Hartmut’s talk ILIAS WG1, March 2008

  15. Projections to uncalibrated errorpoints • In order to rule out any strange effects from calibration process we wanted to do noise projections to the uncalibrated errorpoints. • The gap turns to be of same size as for h(t) projections. ILIAS WG1, March 2008

  16. Frequency domain and time domain projections agree pretty well. For more details, see Jerome‘s talk Time domain noise projections • Wanted to perform noise projections in time domain => taking phase correlations into account. ILIAS WG1, March 2008

  17. New Projection: Beam jitter on main PD ILIAS WG1, March 2008

  18. ILIAS WG1, March 2008

  19. Needs more attention and investigations …. Holographic noise http://arxiv.org/abs/0709.0611 http://arxiv.org/abs/0706.1999 http://arxiv.org/abs/astro-ph/0703775 ILIAS WG1, March 2008

  20. New Ideas are welcome . . . ... even more desperate ones ... ILIAS WG1, March 2008

More Related