[Gep5] SLAC energy resolution

[Mark Jones]

Looks good. Maybe with the 24 GeV data you get more sensitive to the shower
spreading to the other blocks that are not well calibrated. Is there enough data
to look at the energy resolution with the beam position off center? Maybe we could
at least look at the energy measured in the center block compared to GEANT.

                         Mark

----- Original Message -----
From: "Carlos Ayerbe-Gayoso" <gayoso at jlab.org>
To: Gep5 at jlab.org
Sent: Thursday, August 1, 2013 5:39:50 PM
Subject: [Gep5] SLAC energy resolution

Hello everybody

Matthew has finished his analysis of the energy resolution from the SLAC 
test. Following the suggestion from Mark due to the linearity of the 
energy calibration for two, three electron in the 3GeV setup, he added 
those points obtaining the attached result.

Besides, he neglected the use of the 9GeV setup since the spectrum is 
not so clean as the other setups. Also, he rejected the 24 GeV and 36 
GeV peaks from the 12 GeV set up.

Perhaps the 24 GeV should not be rejected (it should be discussed 
comparing how far of linearity is such calibration), but the 36 GeV is 
clear to be rejected since its position was very close to the limit of 
the ADC range causing some overflow problems.

I suggested him to make the fit only with the stochastic A/sqrt(E) and 
calibration tems C, since Avoni paper only presents those two terms.  
Avoni paper presents 10.8%/sqrt(E) and 1.4%.

As you can see, Matthew achieve 11.2%/sqrt(E) but a negligible C term.

I think it is a very good result, and more or less confirm that the 
outer modules are in quite good state.

Thank you very much

Greets

Carlos

_______________________________________________
Gep5 mailing list
Gep5 at jlab.org
https://mailman.jlab.org/mailman/listinfo/gep5