Re: More OMC theory

[Tom Banks <tbanks@socrates.berkeley.edu>]

> BTW thanks for your clear answers to my questions. Obviously I forget
> the point that you are calibrating your scatter muon detection
> efficiency. Still, there is the basic criticism that the scatter detection
> effiency is angle dependent and, given the strong forward preference of
> the Rutherford cross section, you are calibrating with easier tracks,
> not the most nasty ones. It is difficult to argue that the
> MWPC hits quantitatively resolve this issue. So I will keep working
> on that for a bit (after the conference).

I have thought some more about your scattering concerns after sending my
initial e-mail response.  Although I agree with your point that there is
probably some as yet unknown angular dependence in my efficiency for
detecting scattered muons, I think the Run8/MC comparison plots in my
report's Figure 25 provide strong evidence that I'm probably not missing
too much.  Although the MC statistics there are somewhat low, you can see
that there don't appear to be many MC scatters in the large-angle "wings"
outside of my red Run8 distribution (the plots in the bottom row in Figure
25 are probably most relevant here ).  Judging from the plots, I find it
hard to believe that I could be missing as much as 50% of the dangerous,
large-angle scatters, as you had speculated in your last mail.  If I were,
you would see large tails in the MC distributions at +/- Pi/2.

Would you agree with that reasoning, or am I missing something in your
argument?

Tom