Re: updated geometry

[Richard Jones <richard.t.jones@uconn.edu>]

Beni,

I think the truth is somewhere in between.  I strongly suggest that we 
leave it in and simulate it.  If it shows that the resolution and 
low-energy thresholds are acceptable, then we are home free.  If we see 
that there are problems, then we need a detailed simulation (a-la 
Regina's standalone) to get the response right.  Since Matt et.al. are 
working on it right now, we could get a pretty quick response and might 
clear up this issue right away.

Richard Jones


Beni Zihlmann wrote:
> Hi All,
> talking to Elton I think this issue with the Aluminum plate is more 
> tricky.
> Here is the deal.
> The 8mm Aluminum are supposed to replace the first 0.5mm lead of the 
> lead/scintillator
> matrix. So after the last scintillator layer this aluminum plate is 
> glued on instead of a lead
> layer with the aluminum being so thick that it is equivalent to the 
> last layer of lead. That is
> where the 8mm thickness is coming from.
> This means I have a problem modeling this in the geometry file because 
> the active volume
> of the calorimeter is already defined as a mixture of 
> lead/glue/scintillator. So I can not simply
> replace the innermost 0.5mm lead by 8mm aluminum.
>
> My conclusion of this problem is that we should leave it as it is 
> without aluminum plate
> for the simulation because this is the closest to reality in terms of 
> radiation length and that
> is probably more important/critical than the additional volume size.
>
> What is your opinion?
>
> cheers,
> Beni