[Frost] Comparing fsu-EC with cmu-EC

[Michael Dugger]

Hi,

It does not make any sense to show the energy correction for the Carbon 
target when the assumed reaction is "gamma p -> p pi+ pi-". We should 
probably stop showing these energy corrections for Carbon. It is 
misleading

There is no over-determined reaction that we can look at for the Carbon 
target. There will always be some nuclei recoil that is not seen. For this 
reason, there is not enough information to completely determine the 
momentum and energy corrections for the Carbon target.

The only value of the Carbon target is for subtraction purposes. We will 
have to assume that the energy and momentum corrections for Carbon are 
derivable from the other targets. Most likely, the energy/momentum 
corrections for CH2 will be used for the Carbon.

The current situation is that FSU and CMU are in large disagreement. The 
ASU results match more closely with the CMU corrections. The only thing 
that I know for sure is that something is wrong with at least one 
tagger-correction analysis :(

-Michael

On Mon, 30 Aug 2010, Sungkyun Park wrote:

> Hi,
>
> I make plots to compare fsu EC with cmu EC in the following web:
>    http://hadron.physics.fsu.edu/~skpark/research/research_aug3010.html
>
> fsu EC means that I applied Michale's tagger correction and Sung's energy correction together.
> * The red points are the fsu EC.
> * The blue points are cmu EC.
>
> The unit of the Y axis is GeV.
> In the x axis, there are three kinds of version;  E(mea. photon)/ 2.478 , Z-Vertex [cm],and phi [degree]
>
> I did not subtract the carbon influence from the butanol and ch2 target.
> I will update plots to remove the carbon influence soon.
>
> Sung
> Florida State University
>
>
>
>