40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Entry  Thu Dec 9 01:14:42 2010, Osamu, Update, SUS,  20101208_ITMX_jump2.png
    Reply  Thu Dec 9 11:13:37 2010, Osamu, Update, SUS,  jump_oplev_offset.png
Message ID: 4035     Entry time: Thu Dec 9 11:13:37 2010     In reply to: 4033
Author: Osamu 
Type: Update 
Category: SUS 
Subject:  

Quote:

After Kiwamu had set the free swinging mode for ITMX and ETMX, I found a big jump of ITMX pitch and yaw. This jump is shown on oplev and OSEM plots.

20101208_ITMX_jump2.png

I talked with Kiwamu on the phone that a shutdown of suspensions does not add a big offset, and so that it should not make a big jump.

We were not sure that this jump was due to the shutdown or drift or something else. Anyway I put ITMY oplev on center again at 0;57am.

In this morning, the same thing happened but to opposit direction when Kiwamu activated ITMX and ETMX. Then it turned out that 1000ct offset was existing on pit of ITMX. Erasing the offset fixed ITMX to normal position.

However a big drift exists in 11hours plot on ITMX 0.1->-0.25 at OLPIT, -580->-605 at SUSPIT and 0.08->0.15 at OLYAW, no significan drift at SUSYAW. On the other hand, ETMX has no big drift but has 10-30minites order fluctuations.

After 6am both the drift and the fluctuation became, roughly saying, 10 times larger, probably due to the human activity.

 

jump_oplev_offset.png

ELOG V3.1.3-