nutsinee.kijbunchoo@LIGO.ORG - posted 22:39, Friday 03 April 2015 - last comment - 23:52, Friday 03 April 2015(17681)
Seismic bumbling line and temperature correlation
Nairwita, Nutsinee
Attached below are the plots of EX CPS sensor vs. EX VEA temperature and EX roof temperature on March 27th and 28th. The more steady line seems to correlate with the roof temperature (out-door) somewhat while the more fluctuated line seems to correlate more with the VEA temperature. We weren't able to get the raw trend of the PEM so the resolution isn't too great. Judging from the data of March 27th CPS vs. VEA temperature, the temperature became steady around 06:00:00 while the bumbling line starting to settle around 08:00:00. Maybe this two-hour delay in response to the temperature can give us a clue of where the source of the bumbling line might be?
Images attached to this report
Comments related to this report
There are two lines in ETMX, one of which remains between 50Hz to 100Hz and other one is varying through a large frequency rage (around 10-400Hz). The second line is not visible on 2nd April's spectrogram ( https://ldvw.ligo.caltech.edu/ldvw/view?act=getImg&imgId=67607 ) of the CPS sensor but it is clear from 1st April's spectrogram ( https://ldvw.ligo.caltech.edu/ldvw/view?act=getImg&imgId=67615 ) that it actually exists and it's going outside of the frequency range (above 256Hz) and clearly visible in GS13's spectrogram ( https://ldvw.ligo.caltech.edu/ldvw/view?act=getImg&imgId=67616 ). Also to confirm that the the only exists at ETMX, I have done some follow up study on ETMY. There was only one line which could be noticed from 7p.m. on 12th March in the Stage 2 CPS spectrogram and it disappeared around 3a.m. (See the attachment). I did not find two prominent lines like in ETMX. I am looking at the other ISI sensors at ETMY as there is possibility of finding the line at some higher frequency range.
Non-image files attached to this comment
