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Update on Pb-Pb spectra

HMPID weekly meeting

CERN, 19/09/2013

G. Volpe

Updates

• Monte Carlo statistics to evaluate PID efficiency has been increased.

• Corrected spectra evaluated in central and semi-central collisions (0 – 50 %)

Spectra in Pb-Pb collisions: pions (0-50 % centr.)

Corrected spectra

PRELIMINARY

Centrality bins:0 – 5 %5 – 10 %10 – 20 %20 – 30 %30 – 40 %40 – 50 %

Spectra in Pb-Pb collisions: kaons (0-50 % centr.)

Corrected spectra

PRELIMINARY

Centrality bins:0 – 5 %5 – 10 %10 – 20 %20 – 30 %30 – 40 %40 – 50 %

Spectra in Pb-Pb collisions: kaons (0-50 % centr.)

Corrected spectra

PRELIMINARY

Centrality bins:0 – 5 %5 – 10 %10 – 20 %20 – 30 %30 – 40 %40 – 50 %

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Conclusions

• Pb-Pb corrected spectra have been evaluated in central and semi-central collisions (0-50%).

• Main corrections have been applied (tracking eff., PID eff., distance cut).

• To do: • Further increase Monte Carlo statistic for PID efficiency

evaluation. • Cross check PID efficiency from MC with that extracted from real

data (V0’s decays).• Estimate feed-down correction.

Backup

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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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Primary tracks multiplicity