Dear Dan, Peter et al I have modified and run my GEANT model now several times following your suggested MuLAN micromodel miniturization, and went then back to a full model with the results shown in the attached note. Looking closer however made me real wonder what GEANT does with decay in flights (section 2.2) and I am not sure what one should really conclude from that. However the effect of the EMC wires on the muon energy distribution at the target seem to be trustworthy to me. Have a nice weekend Bernhard ******************************************************************* Bernhard Lauss E-Mail: lauss@socrates.berkeley.edu Physics Department 366 LeConte Hall University of California @ Berkeley Berkeley, CA 94720 Tel: (510)-642 4057 United States Fax: (510)-642 9811 ******************************************************************* On Wed, 18 Jan 2006, Peter Kammel wrote: > Dear Dan, > > Let's call Bernhard at a suitable time tomorrow and discuss the > issue with him. > > Regards > > Peter > > On Tue, 17 Jan 2006, Dan Chitwood wrote: > > > This is a very basic calculation and measurement, but it looks like the > > number of low momentum hits seen with the beam is at least on the same > > order of magnitude as one would expect from wire collisions. > > Looking at a few of the momentum distributions, I found a ratio, R, of > > low momentum to normal stops of somewhere between 0.03 and 0.04 > > If I take the wire to empty space area ratio for a wire chamber and set > > it equal to R, I find the formula 2W/L = R where W is the width of the > > wires and L is the inter-wire spacing. This assumes nothing about the > > difference between path lengths through the wire. I don't know the > > specs for the muPC, but these numbers seem consistent with the EMC where > > I believe L=1 mm and W~0.02 mm. > > > > -- Dan > > > >
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