On the Characteristics of the Neutrino Events in (Ultra-)High Energy Astrophysics Experiments from...
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On the Characteristics of the Neutrino Events in (Ultra-)High Energy
Astrophysics Experiments from the view point of Energy Estimation
Akeo Misaki
Research Institute For Science and engineering, Waseda Un
iversity, Tokyo, Japan
Invitation to a point in dispute
• The Fundamental parameters in (Ultra-)High Energy Astrophysics are:
1.Reliable Estimation of the Energies of the Neutrino Events2. Reliable Estimation of the Incident Direction of the Neutrino
Events
To invite the participants to a point dispute, let us start from CONCLUSION, not INTRODUCTION.
Conclusion 1
1. Muon Neutrino Events: Inevitably Partially Contained Events
One could not even estimate the energies of the muons from muon neutrino events (! ?)
2. Electron Neutrino Events: Usually, Fully Contained Events. Inevitably, Partially Contained Events in Ultra-High Energies (LPM shower)
Conclusion 2
• COMPUTER NUMERICAL EXPERIMENTS
• should be carried out simultaneously together with the REAL XPERIMENTS CONCERNED, not in the usual sense of Monte Carlo Simulation.
Range Fluctuation of (Ultra)-High Energy Muons
• The Muon Range with Definite Energy is governed by the stochastic characters of the direct electron pair production, remsstrahlung and nuclear interaction which are also the origins of the accompanied electron showers.
Range Fluctuation of (Ultra-) High Energy Muon
The Image of (Ultra-)High Energy Muon
• Muons from Muon Neutrino Events should be recognized as an aggregate of electron cascade showers with different starting points and different primary energies.
• “Electron clouds” are twined around such the muon.
• Namely, the muon could not be imaged as “Single or Naked Muon “
Is the Muon Itself the Dominant Source for the Cherenkov Light ?
• For the question, it enough to examine the track lengths concerned, because the Cherenkov light production is proportional to the corresponding track length.
• Ratio= track lengths of electrons from the accompanied showers/(track lengths of electrons from the accompanied showers + track length of the muon )
The transition curves for the integral of the track lengths from the muon as whole
Cherenkov Light from the Mother Muon and Her Daughters Electron Shower
• Accompanied electron showers are produced fr
om the direct electron pair production, beremsstrahlung and nuclear interaction due to muon.
• These electron showers are exactly simulated in one-dimensional treatment .
• The electron segments in the simulated electron showers produced corresponding Cherenkov light
The Exactly Simulated Energy Losses of a Muon with 100 TeVas the Function of the traversed depth
The Exactly Simulated Energy losses of a Muon with 1 PeV as the function of the traveresed distance
Five Examples of Transition Curves for the Cherrenkov Light
Cherenkov Photon Number Distribution at 1000m
Cherenkov Light vs. Muon Energy
EμCherenkov Light(t) N=N+1
Eμ
Random sampling of Eμ from Eμ- (γ+1) dEμ
N N≦ max
N=1
Yes
No
A production Spectrum for MuonNμ(Eμ)dEμ E∝ μ
- (γ+1) dEμ
For given γ
Energy Estimation of Muon for given Cherenkov Light 1
Energy Estimation of Muon for Given Cherenkov Light 2
The LPM showers as Partially Contained Events
• The Characteristics of the LPM showers:
• [1] The Average behavior of the LPM showers is quite different from that of BH (Bethe-Heitler) Showers ( Konishi,Misaki and Fujimaki, Nuovo Cimento,(1978))
• [2] TheIndividual Behavior of the LPM shower is quite different from that of the Averaged LPM shower ( Konishi,Adachi,Takahashi and Misaki, J.Phys.G, (1991))
•
Nuovo Cimento 48A, 509 (1978)
The first prediction on the characteristics of the LPM shower
LPM LPM
BH BH
E0/Em=103 E0/Em=103
The first prediction on the multi-peak structure of the LPM shower.
E0=1017 eV Emin=109 eVThe same LPM shower with different threshold energies.
Eth=109 eV
Eth=1012 eV
Eth=1014 eV
Multi-peak threshold
The LPM shower with deep crevasse.
E0=1017 eV
Em=109 eV
The first description on the average behavior of the LPM shower in water.
Fractional dissipated energies of the LPM shower in water.
4848 cu = 1700 meters
LPM shower electron number E0=10^15 eV LPM shower in Water
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
0 5 10 15 20 25 30 35 40 45 50
depth ( m )
No.
of e
lect
ron
1系列2系列3系列4系列5系列6系列7系列8系列9系列10系列
Emin=109eVEprim=1015 eV
LPM shower track length E0=10^15 eVtrack lenghts of LPM shower in Water
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
1.0E+06
0 5 10 15 20 25 30 35 40 45 50
depth ( m )
track
leng
th (
m ) 1系列
2系列3系列4系列5系列6系列7系列8系列9系列10系列
Emin=109eVEprim=1015 eV
LPM shower electron number E0=10^18 eV LPM shower in Water
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
0 20 40 60 80 100 120 140 160 180 200
depth ( m )
No.
of e
lect
ron
1系列2系列3系列4系列5系列6系列7系列8系列9系列10系列
Emin=1012eVEprim=1018 eV
LPM shower track length E0=10^18 eVtrack lenghts of LPM shower in Water
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
1.0E+06
0 20 40 60 80 100 120 140 160 180 200
depth ( m )
track
leng
th (
m ) 1系列
2系列3系列4系列5系列6系列7系列8系列9系列10系列
Eprim=1018 eV Emin=1012eV
LPM shower electron number E0=10^21 eV LPM shower in Water
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
0 100 200 300 400 500 600 700 800 900 1000
depth ( m )
No.
of e
lect
ron
1系列2系列3系列4系列5系列6系列7系列8系列9系列10系列
Emin=1015eVEprim=1021 eV
LPM shower track length E0=10^21 eVtrack lenghts of LPM shower in Water
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
1.0E+06
0 100 200 300 400 500 600 700 800 900 1000
depth ( m )
track
leng
th (
m ) 1系列
2系列3系列4系列5系列6系列7系列8系列9系列10系列
Emin=1015eVEprim=1021 eV
Final Conclusion
• At the early stage of the REAL XPERIMENTS, COMPUTER NUMRERICAL XPERIMENT should be being carried out with parallel them, collaborating with them closely.
• In the presence of the Computer numerical experiment, one need not the transformation from the Cherenkov light to the Muon Energy