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Comparison of QGS with Different String Framentations
J. YarbaFermilabGeant4 Hadronic Meeting3/20/2013
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General Remarks
Done within test19 QGS is paired with
– G4QGSMStringFragmentation (older code)– G4LundStringFragmentation (newer version)
Compared vs FTF – always paired with– G4LundStringFragmentation
Compared vs NA49, NA61 data
Julia Yarba, FNAL – 3/20/20132
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Test19:158GeV p on C -> p, pbar, n, pi+, pi-
dN/dxF
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Julia Yarba, FNAL – 3/20/2013
QGS+G4LundStringFragmshows good results at high energy for secondary pbar, pions
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Test19:158GeV p on C -> p, pbar, pi+, pi-,
d<pT>/dxF
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on C -> pi- +X
(different theta bins)
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on C -> pi- +X
(different theta bins)
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on C -> pi+ +X
(different theta bins)
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on C -> pi+ +X
(different theta bins)
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on C -> p +X (different theta bins)
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on C -> p +X (different theta bins)
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on – K+/pi+ 20<theta<140mrad
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Julia Yarba, FNAL – 3/20/2013
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Test19:31GeV p on – K+/pi+ 140<theta<240mrad
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Julia Yarba, FNAL – 3/20/2013
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Summary
Is there a particular reason why not use G4LundStringFragmentation with QGS ???
In my opinion, QGS+G4LundStringFragmentation gives good results at high energy (158GeV)
In the range of several tens GeV (e.g. 31GeV) the “old” approach seems better (FTF+G4Lund or QGS+G4QGSM)
I think potentials of QGS should be revisited
Julia Yarba, FNAL – 3/20/201313