Difference between revisions of "Reconstruction, June 9, 2009"

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* [[Reconstruction References]]
 
* [[Reconstruction References]]
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# ''[http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PRLTAO000100000005052003000001&idtype=cvips&prog=normal Simultaneous Photoproduction of eta and pi0 Mesons on the Proton]'', PRL 100, 052003 (2008) DOI:10.1103/PhysRevLett.100.052003
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# [https://halldweb.jlab.org/DocDB/0008/000856/001/pythia_data_v1.pdf Gluex-doc-856]
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#* <font color=green>''Pertinence'': </font>
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# [https://halldweb.jlab.org/DocDB/0009/000985/002/GX_calorimetry.pdf GlueX Calorimeter Review Feb 2008]
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#* ''Abstract'': The analysis of the γp → &eta; π0 p reaction has been performed using data from the GRAAL experiment. The total and differential cross sections and the beam asymmetry have been obtained from threshold up to 1.5 GeV of beam energy. The two resonances S11(1535) and Δ(1700) are expected to be excited in the intermediate states of this reaction. The results are used to test predictions based on the assumption that both resonances are dynamically generated from the meson-baryon interaction provided by chiral Lagrangians. The term involving the Δ(1700) excitation, followed by the decay into &eta;Δ(1232), is found to be dominant.
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= Tentative Agenda =
 
= Tentative Agenda =
  
 
# Review Reconstruction Plans in list above
 
# Review Reconstruction Plans in list above
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# a2 cross section papers
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# a2_1320
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##[[Image:Lg triangle yellow questionmark.gif|20px]]&eta;'s and &pi;0's are not separate objects (as much as I understand) that I can apply cuts to when looking at the 4 photon invariant mass in the current code. The &eta; doesn't know that I also made a &pi;0.
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##proton reconstruction is now included via HDParSim
 
# bggen and Pythia
 
# bggen and Pythia
 
## HOW-TO:
 
## HOW-TO:
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##* filter_HighE: Filter out events with total neutral energy less than 6GeV.  
 
##* filter_HighE: Filter out events with total neutral energy less than 6GeV.  
 
##* hdgeant: run the background thrown data set through hdGeant.
 
##* hdgeant: run the background thrown data set through hdGeant.
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##* fCalTree: reconstruction possible pi0s and etas and a2.
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##* fCalTree: reconstruction of possible pi0s and etas.[[Image:Lg triangle yellow questionmark.gif|20px]] &eta;'s and &pi;0's are not separate objects
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# Discussion on Analysis
 
# Discussion on Analysis
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== a2(1320) analysis ==
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[[Image:PhotEThrownE 2D.png|400px| reconstructed photon energy ratio as a function of thrown neutral energy|]][[Image:PhotEThrownE fit.png|400px| reconstructed photon energy ratio]]
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Above:reconstructed energy ratio as a function generated energy
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[[Image:Photonmultiplicity.png|400px]]
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Above:Photon multiplicity
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[[Image:4gammamass.png|400px]]
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Above: invariant mass distribution selecting events with only 4 reconstructed photons
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== pythia background ==
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[[Image:Bggen photEThrownE 2D.png|400px]]
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Above: photon energy fraction as a function of Thrown energy. '''Full of Fail.'''
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[[Image:Bggen photmultiplicity.png|400px]]
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Above: Pythia photon multiplicity after neutral energy filtering and reconstruction.
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[[Image:Bggen 4gammaEtot nPhot4.png||400px]]
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Above: invariant mass distribution selecting events with only 4 reconstructed photons from Pythia background.

Latest revision as of 12:38, 14 March 2017

Time: 11:00 EST/10:00 CST

Reconstruction To Do List

  1. Generation
    1. BoxChecked2.gif Use genr8 for a2 production
    2. BoxChecked2.gif Skim off (hd_filter) the wanted events by cutting on the total neutral energy (> 6 GeV) but record the total number of events before skimming. The resulting MC data set will be stored for general use.
    3. BoxChecked2.gif Use Pythia for background generation after removing a2 → η π0 from the MC data stream as well as events with total neutral energy <= 6GeV.
    4. BoxChecked2.gif Use a2 charge exchange production xsection vs pythia total xsection to estimate number of signal and noise eventsLg triangle yellow questionmark.gif 124μb @ 9GeV ?
  2. Analysis
    1. BoxChecked2.gif After pruning the Pythia events, check the generated vs. reconstructed energy in a plot.
    2. BoxUnchecked2.gif Look at the a2 mass peak - adjust cuts on the eta and pi0 masses then look at the effect on the different angular distributions (i.e. Gottfried-Jackson angles, etc.)
    3. BoxUnchecked2.gif look at difference between reconstructed and generated z position for less than 65 cm
    4. BoxUnchecked2.gif look at single photon reconstruction efficiencies
    5. BoxUnchecked2.gif adjust the error matrix for the BCAL (look in PID/DPhoton_factory.cc)
  3. BoxChecked2.gif Gather all relevant DocDB documents and cross section publications at one spot on the Wiki.

Documents to Review

  1. Gluex-doc-856
  2. GlueX Calorimeter Review Feb 2008

Tentative Agenda

  1. Review Reconstruction Plans in list above
  2. a2_1320
    1. Lg triangle yellow questionmark.gifη's and π0's are not separate objects (as much as I understand) that I can apply cuts to when looking at the 4 photon invariant mass in the current code. The η doesn't know that I also made a π0.
    2. proton reconstruction is now included via HDParSim
  3. bggen and Pythia
    1. HOW-TO:
      • bggen: by default uses the photon beam spectra over 0.15 to 12 GeV. Cross-section??. This has to be modified in fort.15 to 9GeV for us to compare cross sections. This also now dramatically increases our background data set by a factor of 10 over the default beam energy. Why is there a limit on 2.2 million events?
      • filter_HighE: Filter out events with total neutral energy less than 6GeV.
      • hdgeant: run the background thrown data set through hdGeant.
      • fCalTree: reconstruction of possible pi0s and etas.Lg triangle yellow questionmark.gif η's and π0's are not separate objects
  4. Discussion on Analysis

a2(1320) analysis

PhotEThrownE 2D.pngreconstructed photon energy ratio

Above:reconstructed energy ratio as a function generated energy

Photonmultiplicity.png

Above:Photon multiplicity

4gammamass.png

Above: invariant mass distribution selecting events with only 4 reconstructed photons

pythia background

Bggen photEThrownE 2D.png

Above: photon energy fraction as a function of Thrown energy. Full of Fail.

Bggen photmultiplicity.png

Above: Pythia photon multiplicity after neutral energy filtering and reconstruction.


Bggen 4gammaEtot nPhot4.png

Above: invariant mass distribution selecting events with only 4 reconstructed photons from Pythia background.

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