[Halld-cal] Discussion of Bcal readout segementation

[Zisis Papandreou]

Hi Elton:

I would add as a longer-term goal the careful examination of the  
reconstruction algorithm as inherited from KLOE.  We will investigate  
whether other algorithms are more suitable to the GlueX goals as far  
as BCAL reconstruction goes.

Cheers, Zisis...

On 16-Dec-10, at 6:35 AM, Elton Smith wrote:

>
> Dear collaborators,
>
> Yesterday we had a small phone conference to go over initial
> calculations of the resolution for various segmentations of the SiPM  
> into
> Bcal readout channels. Below are some reference notes. Work and  
> further
> discussion will continue in the new year.
>
> Cheers, Elton.
>
> -------------------------------------
> Phone conference Dec 15, 2010 to discuss first look at Bcal readout
> segmentation
> Attending: Zisis, George, Andrei, Irina (UofR), Elton (JLab); Matt,  
> Dan
> (IU), Will (USM)
>
> o We reviewed plots of fractional energy resolution that Dan  
> produced with
> the new reconstruction code for the Bcal. Dan Bennet generated plots  
> of
> energy resolution for photons generated between 0.04 and 2 GeV,  
> uniformly
> along the calorimeter and uniform in azimuthal angle. The resolution  
> was
> calculated for various groupings of inner and outer layers and divided
> into three lengths along the calorimeter module.
>
> o The readout of individual SiPMs always gave the best resolution.
> However, coarser subdivision of the outer region (2.2) did not  
> degrade the
> resolution very much relative to a 4.4 readout.
>
> o Nominal summing of inner SiPM grouping of 2.4 (2 radial, 4  
> azimuthal)
> resulted in the fractional energy resolution degraded by about 10%  
> at the
> lowest energies.
>
> o Further work:
> - Check outer segmentation of 4.1 vs 2.2.
> - Check inner radial segmentation of six layers into two readout
> channels of of 3+3 (nominal) vs 2+4. [Note that Dan's notation does  
> not
> allow for unequal number of channels to be summed].
> - Investigate the z position resolution for these different  
> configurations
> - (Leave the phi segmentation at 4 for the inner region).
>
> o Dan will send Andrei and Irina general information about how the  
> plots
> were generated. This will include copies of root scripts, etc.  
> Andrei and
> Irina will try to reproduce the existing energy resolution plots as  
> a step
> for further investigations.
>
> Let me know if I forgot something or misinterpreted anything. I will  
> send
> this out tomorrow morning to the listserver.
>
> 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
> _______________________________________________
> Halld-cal mailing list
> Halld-cal at jlab.org
> https://mailman.jlab.org/mailman/listinfo/halld-cal

---
Dr. Zisis Papandreou		|  email: zisis at uregina.ca
Department of Physics	|  tel. : (306) 585-5379
University of Regina		|  tel. : (306) 585-4149
Regina, SK  S4S 0A2		|  fax. : (306) 585-5659
World Wide Web:   http://web.me.com/zisis/professional/