Displaying report 1-1 of 1.
Reports until 16:12, Saturday 16 January 2016
H1 General (OpsInfo)
corey.gray@LIGO.ORG - posted 16:12, Saturday 16 January 2016 - last comment - 12:27, Monday 18 January 2016(24994)
H1 Back To Observing....finally

So after the long overnight-lock, H1 dropped out of lock mid-shift (Robert was at EY, but we were running ragged for the last few hours with fairly high low-frequency seismic motion).  

Note:

There were a few new tricks which Sheila taught me when we were working on locking H1 in these noisy conditions:

1)  When the ALSy was having trouble locking, we did a Clear History (yellow button on the ALS screen).  This then gave us a very misaligned Y-arm (but this was taken care of fairly easily by adjusting only yaw on only ETMy).

2) While waiting for PRMI, POP 18 & 90 looked pretty bad.  So, while in this state, the PRM was misaligned and then we adjusted the BS by eye while looking at ASAIR video.

These were two new tricks which I was not aware of.

Comments related to this report
krishna.venkateswara@LIGO.ORG - 12:27, Monday 18 January 2016 (25007)

I just wanted to mention that the 'odd' behaviour in the 0.03-0.1 Hz band (EQ band) was caused by the larger than usual primary microseismic motion, which is peaked at 60-70 mHz (seen in the spectra) . This is usually small at Hanford and large at Livingston, which is the reason their EQ band rms is always larger. In the presence of a lagre primary microseism, the 90 mHz blend will almost certainly give worse performance due to it's gain peaking near 90 mHz.

So, in addition to wind and the secondary microseism, also watch out for the primary microseism :)

Displaying report 1-1 of 1.