Yutaro, Lucia, Yoshinori,

= ETMX =
The masses were in fixed-end configuration but in free-end, like Picture 1.

== Issue ==
After the drifts during the pumping down had calmed down, we found the following issue:
-- we could not compensate the yaw drift of the TM by using the BF-yaw picomotor at all, even though the masses of the tower part were at the positions where they were just before the pumping down. somehow we could excite the TM-pitch oscillation by using MN actuator though (This was confirmed by looking at the light position of the OpLev by eye).
-- A transfer function from IP-L to IP-L-LVDT lost one peak, the lowesst one, after the pumping-down drift compensation work (1st pdf).
-- when the BF-FR was used, the position of the other keystones were also changed, not only the BF-keystone.

== What we did ==
1. Based on the above, we started to suspect that somewhere in the payload part, likely PF or somewhere in RM-chain, was touching/sitting on the frame, and then we changed the following GAS-keystone height by the FRs: F0/F1/F3/BF (Note that the keystone of the F2 was locked mechanically and thus we could not adjust the height at all)

At first, we found that when BF-FR moved the BF-keystone height to higher position, the F0/F1/F3-keystone position went to lower (opposite) position.This meant that the lower section below the PF was machanically locked (likely sitting) somehow. then by pulling up the keystones by the BF/F3/F1/F0-FRs by some amount, we found a situation like; when we pull up the BF-keystone by BF-FR, only BF-keystone went to higher position and the other keystones were just ringing dwon. This meant the trapped mass became free. (2nd jpg) Also at the same time, we started to find the signal on the QPD (3rd jpg), and the position of IP was changed by some amount.
2. We measured transfer functions of IP and found the lowest resonances at about 70mHz (a bit higher than my expectation though) The situation much improved. (2nd to 4th pdf.)

Now ETMX should be freely suspended and nothing should disturb the alignment work anymore! .. it should be

== Note ==
-- After this adjustment by the F0-fishing rods, it seemed that F0-FR did not work properly anymore; probably due to stuck. This issue is to be fixed in the next vacuum break, at the next December.
-- The other TFs are to be measured for the heakth check soon.