[G14_run] Test on the eloss package

[Dr. A.M. Sandorfi]

I've talked with Eugene - he's on it!
Andy


On 4/10/14, 11:38 AM, "Reinhard Schumacher" <schumacher at cmu.edu> wrote:

> Hello Andy,
> I see, thanks.  We also have to add a couple of millimeters of plastic
> for the Start Counter, and I think Eugene also includes something in the
> calculation for the air after the Start Counter and before the particles
> get to Region One.
> It is probably time to include Eugene in the discussion.
> 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 04/10/2014 11:17 AM, Dr. A.M. Sandorfi wrote:
>> Reinhard,
>> The energy loss is all in the Neodymium, Titanium and copper of the
>> solenoid, and in the Aluminum walls of the magnet can, 80K heat shield and
>> the IBC vacuum can. The loss in the target itself is almost nothing.
>> Andy
>> 
>> 
>> On 4/10/14, 8:52 AM, "Reinhard Schumacher"<schumacher at cmu.edu>  wrote:
>> 
>>> Haiyun et al,
>>> 
>>> Using 500 MeV/c as a benchmark, Eugene's program gives energy losses of
>>> 10.0 MeV for protons and 1.5 MeV for pions.  How thick does this imply
>>> the target material is?
>>>                     protons        pions
>>> all plastic       1.6  cm        0.76 cm
>>> all aluminum      0.74 cm        0.22 cm
>>> 
>>> This shows that the program is internally inconsistent for what it
>>> returns for pions and protons at a given momentum.  But also, the
>>> material thickness the numbers imply seems like a lot:  is the HDIce
>>> target at 90 degree really the equivalent of 1.6cm of plastic or .74cm
>>> of aluminum?  That seems very thick.
>>> 
>>> 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 10:37 PM, Dr. A.M. Sandorfi wrote:
>>>> Thanks Haiyun,
>>>> This provides a direct comparison with my earlier direct calculation,
>>>> tracking the Eloss through sequential layers.
>>>> 
>>>> For protons:
>>>> - 65 MeV kinetic energy corresponds to 355 MeV/c momentum, for which your
>>>> Eloss plot gives 22 MeV for delta_E. It should be 27 MeV.
>>>> - at the upper end of your plot, 1000 MeV/c, or 433 MeV kinetic energy, the
>>>> delta_E seems to be a little under 4 MeV. This is closer, but still too
>>>> low.
>>>> The delta_E shouldn't be less than 5.
>>>> 
>>>> Still the pion Eloss seems to be off the most.
>>>> Andy
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> On 4/9/14, 6:08 PM, "Reinhard Schumacher"<schumacher at cmu.edu>   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
>>>>>> 
>>>>>> 
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>>>> 
>> 
>>