bug in mosaic_simple/anisotropic?

[Gonzalez, Miguel A.]

Hi Kristian,
I write to you because I was doing some tests with the new
monochromator components (mosaic_simple & mosaic_anisotropic)
and to my big surprise I found that I obtained more neutrons
after the Bragg-reflection than before.

I used a perfect collimated beam with dE=0 and then I put a monitor,
the monochromator (rotated the right angle to reflect all the neutrons)
and a second monitor. And then, sending 1000 neutrons I find the 
following:

tequila IN16/Partes> ./test5_mosaicsimple.linux --ncount=1000 eta=30 dif=0  
Detector: moni1_I=1000 moni1_ERR=31.6228 moni1_N=1000
Detector: moni5_I=1057.24 moni5_ERR=38.8623 moni5_N=991

As you can see, 991 n arrive to the second monitor but their average
weight is >1, so I>1000.
I didn't look too much in detail to the component (I will start
studying it now), but do you have already any idea of why this is
happening (or which is the problem when calculating the n weights?)?

Thanks for your help,
Miguel.  
______________________________________________________________________

Miguel A. Gonzalez  
Institut Laue Langevin (ILL)
6, rue Jules Horowitz, BP 156
38042 Grenoble Cedex 9, FRANCE
 
Tel: +33 (0)4.76.20.70.41
Fax: +33 (0)4.76.48.39.06
E-mail: gonzalez at ill.fr
______________________________________________________________________