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Page 1: Fluxes of atmosperic leptons

Fluxes of atmosperic leptons

Dmitry Chirkin

UC Berkeley

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Formula from Gaisser

• works for the flat atmosphere• gives muon flux at the point of production, to describe flux on the surface, need to correct for:• muon energy losses• muon decay

pion and kaon critical energies:

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cos* correction• primary interaction depth depends weakly on energy, at 1 TeV is ~ 85 g/cm2

Definition of critical energy:

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Approximation for flat isothermal atmosphere

at zenith angles

above

isothermal approx:

result:

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Parameterizations

quantities are weighted with

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Parameterizations

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Muon energy losses

decay:

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Fits to muon flux

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Zenith angle dependence

From LVD paper (2000)

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Integrated muon flux

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Result dependence on the fitted region

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Nutrino fluxes

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Results

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Muon charge ratioNeutrino charge ratio

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Conclusions

• cos* correction is important at zenith angles above 70o

• Muon energy losses and decay are important for flux description in the whole range of zenith angles

• Muon fluxes, muon and neutrino charge ratios produced with CORSIKA+QGSJET disagree with other calculations