systems:
--------
BML0..3    inplane
mar        from the wall to chamber(MASK)
Q1         lense on arm of p[latform, HV side near VTX
Q0                 "                          away from VTX
   
     mar is close to Q0

orientation:
------------
mar       chamber UP--------> Y UP
Q1        chamber UP--------> Y UP
Q0        chamber UP--------> Y UP

mar       chamber away from VTX ------> X UP
Q1                 "            ------> Z down
Q0                 "            ------> Z down
Q1        chamber push to HV    ------> X UP
Q0                "             ------> X UP



RESULTS
-------
*sunday 30/1/00; a quiet day?
Slow movement over the day is observed.
 mar=chamber: dY=35 um
 q0=arm     : dY=-20/2 um
 q1=arm     : dY=-35/2 um
 bml inplane : dX,dY nihil

*saturday 29/1/00
Blankets turned off around 15:00, however no T gradients over chamber observed.
mar=chamber: dY=6 um
q0=arm     : dY=-5 um
q1=arm     : dy=-13 um
bml inplane: dX,dY nihil

*friday 28/1/00
first put weights 7,2 -- 15 -- 30 -- 15 -- 7.2
 from 0kg to 30kg
 mar=chamber: dY=-42 um   (at 15kg dY -20)
 q0=arm     : dY=-20/2 um (at 15kg dY=-25/2 um!)
 q1=arm     : dY=-85/2 um (at 15kg dY -40/2)

 bml0..3: dY= -220/2, -220/2, -190/2., -200/2 ---> Sag=-100 um (30kg)

the blanketas were turned on around 15.45
 T gradient at 15.45   0
               16:00   0.3
               16:30   1.8
               17.00   2.2
               17.30   2.5
               18:00   2.7 constant

  mar=chamber: dY +8 um                  (from 16:00 to 18:00)
  q0=arm     : dY=-20/2. um
  q1=arm     : dY=-20/2. um
  bml0..3    : dY=+ 25/2, 50/2, 50/2, 80/2 ----> Sag=+25 um


 
INTERPRETATION:
---------------

For sunday, i expect no movements of the arms, however 45um is lost.

For saturday, no big movement expected, 11um is lost

For friday, for the weigths. 
L_arm=360
Chamber_lengt*0.5=1800
sag/(chamber_length*0.5) = alpha_arm/2 (after some mathematics).
dY_arm=alpha_arm*L_arm
dY_arm=sag*2*360*/1800=sag*0.4
Q0 should move positive with(sag_bml3)  100*0.4 = 40um. 
  
Thus we expect 40um. Observe -10+42=32um


For friday, for the blankets
(notice the smal sag! the bml builders did a good job).
We expect sag_BML3*0.4=-40um*0.4 = -20um, we measure -10-8um=-18um.


Conclusions:
------------
For the weight and blanket tests the measurements resp. 8 only 2um are lost. 
For sunday, i expect no movements of the arms, however 45um is lost.
For saturday, no big movement expected, 11um is lost