Re: "On the Measurement of BCAL Photoelectron Statistics" paper

[Elke-Caroline Aschenauer <elke@jlab.org>]

On Mon, 22 Oct 2007, Elke-Caroline Aschenauer wrote:

sorry, I forgot to mention for muon, so the same studies as in the note
but for muons.

thanks elke


>
> Dear Andrei,
>
> I was wondering you could point me to the MC study corresponding to the photon
> studies George showed in his talk and note from April
> 807-v1 	Brief review of the BCAL and SiPM systems
>
> thanks elke
>
>
>
> > Date: Fri, 12 Oct 2007 13:33:37 -0400 (EDT)
> > From: Andrei Semenov <semenov@jlab.org>
> > To: Richard Jones <richard.t.jones@uconn.edu>
> > Cc: halld-cal@jlab.org
> > Subject: Re: "On the Measurement of BCAL Photoelectron Statistics" paper
> >
> >
> > Richard:
> >
> > There is a problem in your paper: you assumed that the energy deposition
> > in the fibers from MIP muons is close to that from electromagnetic shower.
> > I do not think it's quite correct.
> >
> > From your formula (2), the about 5 MeV energy deposition (from MIP muon in
> > the fibers) should have resolution of
> >
> >  sigma_E = 0.06 * sqrt(0.005) = 0.0042 GeV = 4.2 MeV   (viz., 84% !!!)
> >
> > Simulation with FLUKA gives about 3.5 times less value (see the
> > attachment).
> >
> > The origin of the difference is that in the case of MIP muon (i.e.,
> > cosmics), we just have dE/dx loss but no electromagnetic shower
> > (including NO big spread of the deposited energy over the space volume).
> >
> > So, the most of the "sampling" effects just can not be applied for cosmics
> > analysis, that changes the conclusions of the paper a lot.
> >
> > Thank you,
> > Andrei
>
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 ( `,_' )+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=
  )    `\                                                  -
 /    '. |                                                  +
 |       `,              Elke-Caroline Aschenauer            =
  \,_  `-/                                                    -
  ,&&&&&V         Jefferson Lab                                +
 ,&&&&&&&&:       HALL-D 12C / F381       121-A Atlantic Avenue =
,&&&&&&&&&&;      Mailstop: 12H5          Hampton, VA 23664      -
|  |&&&&&&&;\     12000 Jefferson Ave                             +
|  |       :_) _  Newport News, VA 23606  Tel.:  001-757-224-1216  =
|  |       ;--' | Mail:  elke@jlab.org    Mobil: 001-757-256-5224   -
'--'   `-.--.   |                                                    +
   \_    |  |---' Tel.:  001-757-269-5352                             =
     `-._\__/     Fax.:  001-757-269-6248                              -
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