Update on Pb-Pb spectra HMPID weekly meeting CERN, 04/09/2013 G. Volpe 1
Jan 23, 2016
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Update on Pb-Pb spectra
HMPID weekly meeting
CERN, 04/09/2013
G. Volpe
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Spctra in Pb-Pb collisions: fit exapmples
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Spectra in Pb-Pb collisions: pions raw yields
Centrality bins:0 – 5 %5 – 10 %10 – 20 %20 – 30 %30 – 40 %40 – 50 %
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Spectra in Pb-Pb: kaons raw yields
Centrality bins:0 – 5 %5 – 10 %10 – 20 %20 – 30 %30 – 40 %40 – 50 %
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Spectra in Pb-Pb collsions: protons raw yields
Centrality bins:0 – 5 %5 – 10 %10 – 20 %20 – 30 %30 – 40 %40 – 50 %
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Spectra in Pb-Pb collisions: tracking efficiency
Tracking efficiency convoluted with the detector acceptance in the required rapidity range(MC prod. : LHC12a17a_fix)
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Spectra in Pb-Pb collisions: PID efficiency (0-5 % centr.)
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Spectra in Pb-Pb collisions: PID efficiency (5-10 % centr.)
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Spectra in Pb-Pb collisions: PID efficiency
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Spectra in Pb-Pb collisions: distance cut correction
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Spectra in Pb-Pb collisions: pions (0-10 % centr.)
Corrected spectra
PRELIMINARY
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Spectra in Pb-Pb collisions: kaons (0-10 % centr.)
Corrected spectra
PRELIMINARY
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Spectra in Pb-Pb collisions: protons (0-10 % centr.)
Corrected spectra
PRELIMINARY
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Conclusions
• Pb-Pb corrected spectra have beeb evaluated in two most central centrality bins (0-5%, 5-10%). The same procedure will be applied for the semi central collisions asap.
• Main corrections have been applied (tracking eff., PID eff., distance cut), feed down still missing.
• PID efficiency has been extracted from Monte Carlo. It is a very critical parameter, real data have to be also used (V0’s decays).
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Backup
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Primary tracks multiplicity
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Pb-Pb analysis status: protons PID eff. from V0s
ProtonsAnti-protons From
Francesco
PID efficiency for protons and anti-protons, extracted by means of V0s selection. Difference between the two charge is present.