Introduction of Elbert model to Corsika


Introduction

We have to know the energy distribution of atmospheric muon backgrounds to distinguish between signal muons and background muons, but the energy distribution of atmospheric muon backgrounds calculated by Corsika is not equivalent to that of real data.
So,we have to improve Corsika system to test various model in short time.I thought to introduce Elbert model to Corsika.
First,I examined whether the minimum requirements that Elbert model reproducts present Corsika are satisfied.


Comparison of Elbert model with present Corsika

Fig.1
Energy distribution of atmospheric muon backgrounds

X:muon energy[GeV]
Y:number of muons originating from a primary cosmic ray(7.5<=log(energy[GeV])<8.0, 0.7<=cos(azimuth)<0.8)

Blue:Elbert model
Red:Corsika


Fig.1 shows that Elbert model almost reproducts Corsika.Strictly speaking,the values of Elbert model are slightly smaller than those of Corsika.

Fig.2

First plot
Differences of Elbert model with Corsika
(for various primary cosmic ray energy)

X:muon energy[GeV]
Y:(value of Elbert model)/(value of Corsika) in Fig1

Second plot
Comparison of slope of first plot

All:0.7<=cos(primary cosmic ray azimuth)<0.8

Gray:6.0<=log(primary cosmic ray energy[GeV])<6.5
Skyblue:6.5<=log(primary cosmic ray energy[GeV])<7.0
Pink:7.0<=log(primary cosmic ray energy[GeV])<7.5
Yellow:7.5<=log(primary cosmic ray energy[GeV])<8.0
Blue:8.0<=log(primary cosmic ray energy[GeV])<8.5
Green:8.5<=log(primary cosmic ray energy[GeV])<9.0
Red:9.0<=log(primary cosmic ray energy[GeV])<9.5
Black:9.5<=log(primary cosmic ray energy[GeV])<=10

Fig.3

First plot
Differences of Elbert model with Corsika
(for various primary cosmic ray azimuth)

X:muon energy[GeV]
Y:(value of Elbert model)/(value of Corsika) in Fig.1

Second plot
Comparison of slope of first plot

All:7.5<=log(primary cosmic ray energy[GeV])<8.0

Red:0.1<=cos(primary cosmic ray azimuth)<0.2
Green:0.2<=cos(primary cosmic ray azimuth)<0.3
Blue:0.3<=cos(primary cosmic ray azimuth)<0.4
Yellow:0.4<=cos(primary cosmic ray azimuth)<0.5
Pink:0.5<=cos(primary cosmic ray azimuth)<0.6
Orange:0.6<=cos(primary cosmic ray azimuth)<0.7
Gray:0.7<=cos(primary cosmic ray azimuth)<0.8
Skyblue:0.8<=cos(primary cosmic ray azimuth)<0.9
Black:0.9<=cos(primary cosmic ray azimuth)<=1.0


First plots of Fig.2 and Fig.3 show that the differences between Elbert model and Corsika are less than 100%.
Second plots of Fig.2 and Fig.3 show that we have to introduce the primary cosmic ray energy dependence to Elbert model so that Elbert model strictly reproducts Corsika.Additionaly,higher primary cosmic ray energy become,more the graphs curve.So,we have to introduce the muon energy dependence to Elbert model,too.


Summary

Elbert model almost reproducts present Corsika.(The differences are less than 100%.)
We have to introduce primary cosmic ray energy and muon energy dependence to Elbert model so that Elbert model strictly reproducts present Corsika.

Last modified: Thu March 2 15:08:00 JST 2008