[G14_run] Test on the eloss package

[Haiyun Lu]

Hello Reinhard,

I am not sure if I know the answer to your two questions. In fact, I 
think I don't. But I can give some thoughts or guess.

1. As I stated, I made up all protons from the center of the target. It 
means that every proton will experience the target material of a radius 
thick. That is not the case in the reality. I am not sure how much 
difference this will generate.

2. This is my purpose to directly test the eloss correction program. The 
reason why I used "fake" events instead of real events is that I have 
more control in this case. I have no idea why the program gives small 
correction.

Another clarification may be needed is that the momenta of the proton 
and pion are before eloss correction. I think this should not make a big 
difference.

Regards,
Haiyun
On 04/09/2014 06:08 PM, Reinhard Schumacher wrote:
> Hello Haiyun,
>
> 	Nice work.  Your proton band looks like it gives higher energy loss for
> protons at a given momentum than Dao's and the others'.  At 300 MeV/c,
> your plot shows ~30 MeV energy loss, while Dao's shows ~10 MeV.  For
> pions the behavior is less clear: both your calculation and his give
> less than 2 MeV energy loss at 300 MeV/c, which is very likely too
> small.  So this leads to the questions:
>
> 1) Why do you get higher, probably closer to correct, energy losses for
> protons?
>
> 2) Why does the program give unrealistically small energy losses for
> everybody?
>
> Reinhard
>
> ___________________________________________________________________
> Reinhard Schumacher         Department of Physics, 5000 Forbes Ave.
> Carnegie Mellon University, Pittsburgh, PA 15213, U.S.A.
> phone: 412-268-5177         web: www-meg.phys.cmu.edu/~schumach
> ___________________________________________________________________
>
> On 04/09/2014 05:16 PM, Haiyun Lu wrote:
>> Dear g14ers,
>>
>> I did a straight test on the eloss package of g14. I made up some events
>> of proton and pi-. They are at fixed vertex position at (0,0,-7.5),
>> which is the center of the target. They are at the fix polar angle, 90
>> degree, which is perpendicular to the beam line. The azimuthal angle and
>> the momentum are variable. Then I plot the energy loss versus the
>> momentum for proton and pi-. I attached a file "eloss_test.png". There
>> are two bands in the histogram. The upper one is for proton and the
>> lower one is for pi-.
>>
>> Best regards,
>> Haiyun
>>
>>
>> _______________________________________________
>> G14_run mailing list
>> G14_run at jlab.org
>> https://mailman.jlab.org/mailman/listinfo/g14_run
> _______________________________________________
> G14_run mailing list
> G14_run at jlab.org
> https://mailman.jlab.org/mailman/listinfo/g14_run