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Reports until 20:10, Sunday 25 September 2016
H1 ISC (OpsInfo)
jenne.driggers@LIGO.ORG - posted 20:10, Sunday 25 September 2016 (29965)
New guardian state for checking BS alignment during acquisition

Especially with the DRMI needing alignment help during most re-locks, I have created a new state to help check BS-only alignment.

Recall that if the DRMI flashes don't look so good, you can select the PRMI_Locked state that Sheila created some time ago.  This state will misalign the SRM and attempt to lock the power recycling cavity with the arms held off resonance. 

Sometimes though even these flashes aren't very good, and the PRMI isn't catching lock.  Now you can select the new state Check_MICH_Fringes in the ISC_LOCK guardian, and it will misalign the PRM.  This state is currently not set to try to lock MICH, so it'll never look quite like MICH_dark_locked from initial alignment.  But, you can watch the flashes on the AS air camera, and move the BS until they are as circularly symmetric as possible.  Note that sometimes you'll only see a few flashes per minute, so this requires a bit of patience, but it's often still faster than giving up and doing a full initial alignment.  Once the flashes on the AS air camera are circularly symmetric, re-select PRMI_locked.  This will realign the PRM, and go back to the usual locking sequence.

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