I am interested in doing some analysis to characterise the seismic signal present around the EGO site. I went through auxiliary public data and looked the channel list GW170814/dataprep/chanlist.csv · master · gwosc-public / auxiliary-channels · GitLab
There seems to be ground motion data. Namely
- Ground motion of EX in the IFO basis
- Ground motion of EY in the IFO basis
- Ground motion of LVEA in the IFO basis
What are EX, EY and LVEA? What is the IFO basis?
Hi @zerafachris, just to avoid misanderstanding in case someone reads this post: No seismic signal present around the EGO site have been released to the public and I don’t foresee a release in the near future. Even if they would be released the channel names would be different since we are talking of another detector.
Do you still want to analyse the LIGO data?
Yes, LIGO data would still be good.
Thank you for the question.
- EX refers to the X-arm end station
- EY refers to the Y-arm end station
- The LVEA refers to the corner station
I think “IFO” basis refers to a coordinate axes aligned with the instrument. So - the X-axis would point in the direction of the X-arm, the Y-axis would point in the direction of the Y-arm, and the Z-axis would point up.
You can learn more about this system at http://pem.ligo.org
A helpful guide to acronyms can be found here: https://dcc.ligo.org/public/0002/M080375/024/M080375-v24%20Abbreviations%20and%20Acronyms.pdf
The ones you’re asking about are:
- EX: End station, X arm
- EY: End station, Y arm
- LVEA: Laser and Vacuum Equipment Area (at observatory corner station)
- IFO: Interferometer
The “IFO basis” is a (x, y, z) coordinate system where the x and y axes are the x and y arms of the interferometer, respectively. This allows you to figure out which direction of motion the seismometer is measuring.
(Looks like Jonah beat me to the answer!)