[Halld-cal] Shashlyk resolutions (fwd from Serguei)

[Elton Smith]

---------- Forwarded message ----------
Date: Tue, 23 Feb 2010 10:39:56 -0500 (EST)
From: serguei at jlab.org
To: Elton Smith <elton at jlab.org>
Subject: Re: Shashlyk resolutions

           Hi Elton,
There is a comparison of the Shashlik and GAMAS with the same read out
(old russian PMT - FEU84) and with the same fit procedure. For 500 nm
light from the Shashlik FEU 84 has 7-10 % q.e.. If you used modern PMT
with 20% q.e. you would get 5.5/sqrt(E)(and the constant term about
0.8-1.%). If you used HAMAMATSU APD with 80% q.e. you would get about
5./sqrt(E).
Also the Shashlik could be used as the time of flight detector with E-T
method for the particle identification. You can not use the Pb glass such
way.

 Best regards,
 Sergey.

>
> Hi Serguei,
>
> I took a look at the information about the shashlyk calorimeters and see
> that
>
> 1) In one document I see that both shashlyk and Pb glass results give
> results of order 7%/Sqrt(E) + 1-2%. We believe that for GlueX our new pmt
> coupling will improve the performace below the 7%/sqrt(E) seen in Radphi.
>
> 2) In a second beam test it appears that the resolution is closer to about
> 15%/sqrt(E)
>
> What are the best guesses for the detector resolutions?
>
> Thanks, Elton.
>
> Elton Smith
> Jefferson Lab MS 12H5
> 12000 Jefferson Ave
> Suite # 16
> Newport News, VA 23606
> elton at jlab.org
> (757) 269-7625
> (757) 269-6331 fax
>