mm, relder, liberty, kaf, ebg

Mike, Dick, Bob, Kathy and Gene, 

  Here are some preliminary numbers from the last two
X-GEF runs on proton-exposed gratings:

     Grating/ Test         1 keV    4 keV    8 keV   BarFrac/RectThick

      MA1025/010301   p0:  11.69    25.24    11.40    0.61/4213
      MA1025/001207   p0:  11.09    25.16    11.54    0.61/4272

      MA1026/010301   p0:  12.15    24.34    10.75    0.62/4066
      MA1026/001116   p0:  12.08    24.19    10.68    0.62/4081

      MB1148/010302   p0:  17.29    20.52     8.07    0.49/3353
      MB1148/001117   p0:  17.08    20.90     8.27    0.49/3405

      MB1158/010302   p0:  14.87    22.77     9.53    0.47/3901
      MB1158/001117   p0:  14.75    22.92     9.57    0.47/3848

The top line in each pair is the "after" measurement (as indicated
by the date code under "Test").

These results are for the central strip
region "p0" of the gratings; MEGs are tested
at 5 valid regions; HEGs at 3.  So, in a sense, we get 5 (3) tests
for each grating.

The efficiency values tabulated are the values of the 1st order
efficiency model which best fits the measured efficiency data points;
19 or so individual X-GEF measurements (0th, +/-1st, +/-2nd orders)
go into the model fit.

The "BarFrac" is an approximation to the grating bar 'duty cycle'
in the bizzarre multi-vertex model bar shape, giving an idea of the
line-to-period ratio for the shape.

The "RectThick" is similarly an estimate of the 'average thickness'
of the bar region of the model shape.


  - Dan