[Frost] The preliminary version of a FSU energy correction

Wed Oct 6 16:20:14 EDT 2010

Michael,

Here is the preliminary version of a FSU energy correction.
I need  to correct the FSU Momentum Correction a little. I will update it later.

In the following web, 
  http://www.jlab.org/Hall-B/secure/g9/sungkyun/10-06-10.html

I used new vertex cut.
I have made Energy difference plots in several situations.
  * E_{mea. gamma} / E_{e}
  * E_id 
  * Z-Vertex [cm]
  * phi angle

plots are made after applying ELoss Correction and FSU Energy Correction.
I do not apply the Momentum Correction in these plots.

Sung
Florida State University

----- Original Message -----
From: Michael Dugger <dugger at jlab.org>
Date: Monday, October 4, 2010 5:05 pm
Subject: Re: [Frost] pi0 mass
To: Sungkyun Park <sp06k at fsu.edu>
Cc: frost at jlab.org

> 
> Sung,
> 
> Thanks for the information. For energies below E_gamma/E_e = 0.7 
> the mean 
> of pulls look fairly good. Perhaps the pi+ momentum pull is a bit 
> high and 
> the pi- lambda pull is too low. Overall, this looks promising.
> 
> I think your right, the momentum corrections for the higher 
> energies look 
> like they need to be refined some more.
> 
> The thing that concerns me the most is the problem of having a z-
> vertex 
> dependence in the photon energy correction. We will never get an 
> analysis through committee having a target dependent photon energy 
> correction. (I'm starting to sound like a broken record. Sorry.)
> 
> It looks like you have been busy.
> 
> When you feel like you have preliminary energy/momentum 
> corrections, 
> please feel free to share them so that we can start testing the 
> corrections using different analyses.
> 
> Take care,
> Michael
> 
> On Mon, 4 Oct 2010, Sungkyun Park wrote:
> 
> > Hi, Michael.
> >
> > I checked why the pulls in the high energy have a bad condition.
> > To check these,  I make the six kinds of pull distributions.
> >
> > Plot:
> > ELoss: http://www.jlab.org/Hall-
> B/secure/g9/sungkyun/IMG/Oct0410/Check_Pull_ELoss_AllTarget_Sit04.gif> MomC: http://www.jlab.org/Hall-B/secure/g9/sungkyun/IMG/Oct0410/Check_Pull_MomC_AllTarget_Sit04.gif
> >
> > Notes:
> > In ELoss plots, there are three kinds of pulls.
> > RED -> After ELoss and FSU EC
> > BLUE -> After ELoss, FSU EC, and E_{gamma} / E_{e} < 0.7
> > GREEN -> After ELoss, FSU EC, and E_{gamma} / E_{e} > 0.7
> > In MomC plots, there are three kinds of pulls.
> > RED -> After ELoss, FSU EC, and MomC
> > BLUE -> After ELoss, FSU EC, MomC, and E_{gamma} / E_{e} < 0.7
> > GREEN -> After ELoss, FSU EC, MomC, and E_{gamma} / E_{e} > 0.7
> >
> > If you want to know the means of each number in x-axis, click the
> >   http://www.jlab.org/Hall-B/secure/g9/sungkyun/X_axis.html
> >
> > In ELoss plots, The Eloss in high Energy(Green), the Eloss in low 
> Energy(Blue), and the Eloss in all energy(Red) have the similar
> > patterns.10, 20, and 30 ( mean of photon pull of proton, pi+, and 
> pi-, respectively) have good position. However, 2, 5, and 8 are
> > big. These parts are related of lambda angle. I think these 
> lambda angles parts are fixed after applying magnetic field 
> correction.> Before applying FSU MomC, there are not the major 
> problems.>
> > In MomC plots, The Eloss in high Energy(Green) has a bad 
> condition. Especially, the positions of 1, 4, 7, 10, 11, 14, 17, 
> 20, 21, 24,
> > 27, 30 are bad in Green point. These numbers are related of pulls 
> of mom and photon of proton, pi+, and pi-.
> >
> > I think the wrong positions of photon pulls are happened after 
> applying FSU MomC.
> > The FSU-MomC is worked very well in low energy. In high Energy, 
> this is not enough.
> > I need to check FSU MomC in high energy more.
> >
> > Do I make some plots of the preliminary energy corrections and 
> pi0 mass maden before applying FSU MomC to  fellow FROST 
> collaborators?>
> > Best Wishes
> >
> > Sung
> >
> > Florida State University
> >
> >
> >
> >
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> ----- Original Message -----
> >> From: Michael Dugger <dugger at jlab.org>
> >> Date: Friday, October 1, 2010 4:37 pm
> >> Subject: [Frost] pi0 mass
> >> To: frost at jlab.org
> >>
> >>>
> >>> Hi,
> >>>
> >>> I am seeing differences in the pi0 mass when I plot the pi0 yield
> >>> as a
> >>> function of massX as opposed to massX^2.
> >>>
> >>> Because to CLAS resolution issues, the best way to plot the pi0
> >>> yield
> >>> distribution is how Sung has (massX^2).
> >>>
> >>> For the g1c and g8b data, we extract pi0 yields using massX^2. We
> >>> do this
> >>> to make sure we are not losing pi0 events due to the yield being
> >>> "pinched"
> >>> off at massX<0. I did not think that this "pinching" effect would
> >>> change
> >>> the mass centroid of the pi0 peak by much. In the plots using
> >>> massX, the
> >>> pi0 mass is being shifted upwards by ~10 MeV for Butanol, and ~4
> >>> MeV for
> >>> CH2.
> >>>
> >>> Plots:
> >>> massX CH2:       http://www.jlab.org/~dugger/g9/g9a/tmp/mXCH2.gif
> >>> massX^2 CH2:     
> http://www.jlab.org/~dugger/g9/g9a/tmp/mXsqCH2.gif>>> massX Butanol:
> >> http://www.jlab.org/~dugger/g9/g9a/tmp/mXButanol.gif> massX^2
> >> Butanol:
> >>> http://www.jlab.org/~dugger/g9/g9a/tmp/mXsqButanol.gif
> >>> Notes:
> >>> The only correction applied is eloss
> >>> BLACK-> no Carbon subtraction;
> >>> RED-> scaled Carbon;
> >>> Blue-> Carbon subtracted
> >>>
> >>> Results:
> >>> massX from massX CH2 plot = 142 MeV
> >>> massX from massX^2 CH2 plot = 138 MeV
> >>> massX from massX Butanol plot = 150 MeV
> >>> massX from massX^2 Butanol plot = 140 MeV
> >>>
> >>> This is good news :) The pi0 mass situation is not as bad as we
> >>> have previously thought. Instead of the masses being different
> >> for
> >>> the
> >>> Butanol and CH2 targets by 8 MeV, they are only different by
> >> about
> >>> 2 MeV.
> >>>
> >>> The difference between the pi0 mass as measured by massX
> >>> distributions as
> >>> opposed to massX^2 distributions is being driven by CLAS momentum
> >>> resolution. This might explain why Hideko sees such large
> >>> differences in
> >>> the pi0 mass as a function of CLAS angle.
> >>>
> >>> For E_gamma/E_e, Sung is seeing pi0 masses for the Butanol and
> >> CH2
> >>> targets
> >>> that are within 5 MeV of each other using photon energy
> >> corrections
> >>> that
> >>> (look) to be similar for each target. There is a good chance that
> >>> the 5
> >>> MeV might be attributable to differences in the Carbon
> >> subtraction,
> >>> the
> >>> lack of background contributions being part his pi0 fit routine,
> >>> and
> >>> differences in the photon energy correction.
> >>>
> >>> Since we can not have a target dependence in the photon energy
> >>> corrections
> >>> it would be good to see the pi0 mass for the Butanol and CH2
> >>> targets when
> >>> the photon energy correction is made to be identical to each 
> target.>>>
> >>> Sung, can you make your preliminary energy and momentum
> >> corrections
> >>> available to fellow FROST collaborators? It would be good to
> >> check
> >>> the
> >>> consistency of pi0 mass results between different groups.
> >>>
> >>> Take care,
> >>> Michael
> >>> _______________________________________________
> >>> Frost mailing list
> >>> Frost at jlab.org
> >>> https://mailman.jlab.org/mailman/listinfo/frost
> >>>
> >
> 