CORSIKA simulated EAS database for 80 tanks configurationsamvel/icetop_2010_2.pdfSamvel Ter-Antonyan...
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Reconstruction of All-Particle Energy Spectrum for ICETOP Samvel Ter-Antonyan and Ali Fazely Simulated: 0.1< E 0 <500 PeV < 40 0 p, He, O, Fe R nearest1 <120m Reconstructed: S min =20pe At least 3 stations within R<150m CORSIKA simulated EAS database for 80 tanks configuration
Transcript of CORSIKA simulated EAS database for 80 tanks configurationsamvel/icetop_2010_2.pdfSamvel Ter-Antonyan...
Reconstruction of All-Particle Energy Spectrum for ICETOP
Samvel Ter-Antonyan and Ali Fazely
Simulated:
0.1< E0<500 PeV
< 400
p, He, O, Fe
Rnearest1<120m
Reconstructed:
Smin=20pe
At least 3 stations
within R<150m
CORSIKA simulated EAS database for 80 tanks configuration
Shower core coordinate distributions
Multi-parametric energy estimator for ICETOP Array
6
54
31252
11
cos
cos
aa
aaS
aaE
3
A
iiA
i E
EE
)(
)lnln(
0
2
2
,1,,02
2 /ndf = 1.05i=1,…2000
AH, He, O, Fe
E0>1 PeV
=0.35-0.055Ln(E/PeV)0.07
min{2(a1,a2,…a6,(Ei)| E0,i)}
Energy estimator:
a1 11.21 0.05
a2 2.336 0.042
a3 0.558 0.015
a4 1.200 0.034
a5 0.241 0.004
a6 7.29 0.52
E0 - E1 scatter plots
Energy estimator: 10 EE
Inverse problem
),,,( cossNNe [GAMMA_09]
This work)cos,,( 125 S
11250 },,{ SE [ICETOP_09]
01001 ),,()()( dEAEEWEFEf
is ill-posed problem for F(E0) due to A H, He, … Fe
Redefinition of inverse problem:
a priori: ,~)( 00
EEF
Let ))(|,(),,( 101 ELnAEEW
?),,( NNe[KASCADE-GRANDE]
2
)1(exp)()(
221
EFEf
{
~1960
Solution:
Distribution of energy errors (~ Gaussian)
Energy bias versus shower zenith angle
Inverse problem for ICETOP: f(E1) = F(E0)P(E0)W(E0,E1)dE0
= <E1 / E0> 1 (E0) , (E0) aLn(E0) + b
F(E0) ~ E0-
P(E0)=1 - exp(-E0 /Eth ) , uncertainties: , Eth
2
)1()(exp)()()(
22 EEPEFEf
where E’=E /3.35 and E’’=Eexp[(-b2+0.88a)( -1)]
Fit of solution:
2/
22
2222
2
11
)1()1(~
~
thEE
th
th eE
E
F
F
Total systematic spectral errors:
ICETOP: a=-0.055; b=0.35; =0.07; =1.35; =0.1; Eth=0.6; Eth=0.15
for =2.9 and =0.25
Accuracy of fit of solution ( 2%)
0.02<a<0.09; 0.2< b <0.5; 0.45< Eth< 0.75 PeV; 0.5<E0<700 PeV
Taking into account the threshold
Efficiency
if
then
Expected biases and uncertainties of primary energy
All-particle energy spectrum reconstruction
CONCLUSION
The results are based on 4x5000 simulated shower events for ICETOP80 tanks configuration and primary nuclei A p, He, O and Fe
respectively. The fluctuation of tank signal and shower reconstruction uncertaintieswere taken into account. 6-parametric primary energy estimator provides 10-15% accuracy forE1 PeV and 5-10% for E >10 PeV regardless of primary nuclei kind. On the basis of inverse problem approach the reconstruction methodfor the all-particle primary energy spectrum was developed for ICETOParray. The reconstruction method was tested using 4-component rigiditydependent primary energy spectra.The corresponding all-particle energy spectrum for ICETOP array wasderived taking into account the energy threshold and energyreconstruction biases and uncertainties in the energy range 0.5-500 PeV.
