dE/dx Simulation

Marjan ĆirkovićBelgrade SHINE team

NA49/NA61 Software/Analysis/Collaboration meetingWarsaw, 13.02.2014

Idea of research

• We want to use the same programs for analysis for real and MC data

• dE/dx is used for particle identification, having simulated dE/dx data could improve these analyses

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 1

Bethe-Bloch formula

• Bethe-Bloch formula (dE/dx in function of momentum):

• After parameterization:

• Where:

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 2

−𝑑𝐸𝑑𝑥

=𝐴 (1+𝑘 )−𝐵{ (1+𝑘 ) 𝑙𝑛𝑘+1 }

𝑘=𝑚2𝑐2

𝑝2

dE/dx_momentum positive particles (fitting protons)

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 3

dE/dx_momentumall particles (fitting pions)

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dE/dxReal data - protons

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Real data, Hans BB &Belgrade fit for protons

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σ(dE/dx) for protons

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 7

Real data, Hans BB &Belgrade fit for pions

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 8

σ(dE/dx) for pions

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Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 10

dE/dx Hans cutdE/dx Belgrade cut

Real data for K0dE/dx cut included

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Hans BB Belgrade BB

Thank you!

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Fitting functions

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 13

Protons:

Pions:if p 1.5 GeV/c

Fitting functions

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 14

if p > 1.5 GeV/c

if p 12 GeV/c

Fitting functions

Warsaw, 13.02.2014 Marjan Ćirković, Belgrade SHINE team Page 15

if p > 12 GeV/c

dE/dx_momentumpositive particles (fitting protons)

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dE/dx_momentumall particles (fitting pions)

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