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  Fri May 28 13:32:01 2010, alberto, kiwamu, Update, VAC, vacuum work 
    Reply  Fri May 28 13:51:51 2010, Jenne, Update, VAC, vacuum work 
       Reply  Fri May 28 14:24:30 2010, Jenne, Update, VAC, vacuum work 
Message ID: 3010     Entry time: Fri May 28 13:51:51 2010     In reply to: 3009     Reply to this: 3011
Author: Jenne 
Type: Update 
Category: VAC 
Subject: vacuum work 


We started a vacuum work in this morning. And still it's going on.


Although the last night the green team replaced a steering mirror by an 80% reflector on the PLS table, the beam axis to the MC looks fine.

The MC refl beam successfully goes into the MCrefl PD, and we can see the MC flashing as usual.

We started measuring the distance of the optics inside the vacuum chamber, found the distance from MC3 to MMT1(curved mirror) is ~13cm shorter than the design.

We moved the positions of the flat mirror after the Faraday and the MMT1, but could not track the beam very well because we did not completely lock the MC.

Now we are trying to get the lock of the MC by steering the MC mirrors.



 Hey guys,

I just finished redoing the calc based on the measurements that happened last week.  Using the average of the Vert and Horz measurements in Kevin's elog 2986, I find that we need to make the MMT telescope ~8cm longer.  So, can you please place the flat mirror after the Faraday in the same place as the drawing, but move the MMT1 79mm farther away from that flat mirror?  Looking at the table layouts that Koji has on the wiki, this should still (barely) fit.

New distances:

d2a = 884.0mm (no change) ------  MC3 to Flat after Faraday

d2b = 1123.2mm (move MMT1 farther toward center of BS table)  -------- Flat after Faraday (SM1) to MMT1

d3 = 1955.0mm (result of moving MMT1)  ---------  MMT1 to MMT2

d4a = 1007.9mm (no chnage)        ----------- MMT2 to SM2

d4b = 495.6mm (no change) ------------ SM2 to PRM

ELOG V3.1.3-