[Patrick, Sheila, Jenne]

We are perplexed by the behavior of the new ALSX laser.  In the first attached screenshot, for most of the time after -30min (except a bit arouhnd -10min), we were sitting in Locking_arms_green, so the green lasers were locked to the arms, but nothing else was going on locking-wise (this was concurrent with some IMC diagnostics). 

We see that the green power transmitted through the arm drifts a lot.  It doesn't seem to be exactly following the IR output of the laser (as measured by the FIBR_A_LF_OUTPUT, which should be a combo of IR from the vertex and IR from the end station laser but dominated by the end station laser), although it does sometimes.  During these large drifts the arm was locked on TEM00 of the green beam, as seen on the transmission camera.  The drifts are mirrored by the LASER_GR_LF_OUTPUT, which is a measure of the green power pretty soon after the doubling crystal.  So, this is something that is really happening to the amount of green light going into the arm cavity. 

Also note that in the second attached screenshot, it looks like the output of the new laser is more noisy than the old one. We tried toggling the noise eater switch for the laser remotely from the screen but that didn't seem to affect the behavior. 

It doesn't really look like what I think of as mode hopping of the laser, since it's slow drifts and not fast jumps.  At this point we're pretty confused, and not able to hold ALS COMM lock for very long, so we're hoping that someone can take a look in the morning and help us out.