1. FLUCTUATIONS OF MUON ENERGY LOSSES
Newt
&
Paolo
Original method developed by Peter Steffan

2. ENERGY LOSS Energy loss vs. muon energy:
There are two kinds of processes:
Continuous: ionization
Stochastic: Pair production, bremstrahlung, photonuclear interactions
Above the critical energy (600 GeV in water) stochastic losses dominate.
Very important that this plot only shows the average muon energy loss and no mention of fluctuations

3. Multiple Muon Events
Each muon in a bundle of muons follows its own energy loss procedure depending on the energy of that muon and the energy loss
recorded will be over several muons

4. ENERGY LOSS OF A SIMULATED MULTIPLE MUON EVENT(20TeV)
Fluctuations
due to stochatic
losses
A minimum ionisation loss
component
“Wild” fluctuations
every where

5. FLUCTUATIONS DISTRIBUTION
The peak occurs at the ionization losses level and all the other fluctuations are due to stochastic losses.In particular the ratio of variance to mean of this distribution seems high
Large spread

6. SINGLE MUON EVENT(60TeV)
There is a
Certain degree of
Consistency in
These fluctuations
A minimum ionisation
loss component

7. MULTIPLE MUON EVENT 2
Energy=20TeV

8. MULTIPLE MUON EVENT 3
Energy=5TeV,5muons

9. SINGLE MUON EVENT 2
Energy=10TeV

10. SINGLE MUON EVENT 3
Energy=20TeV

11. Ice Properties
The problem with studying this variable where we observe fluctuation of energy released(amplitude) is that ice properties themselves introduce some fluctuations into
the observed amplitude

12. Reconstructed Errors B A Dust Dust True track Δθ Reco Track Clear Ice
Large Amplitude Seen when lower is
expected from reco track hypothesis B
Dust Δθ
Reco Track
Clear Ice A
Dust
Small Amplitude Seen when large is expected from reco track hypothesis
As photons get scattered in dust they
run out of steam ; This process inherently introduces fluctuations

13. NEW ESTIMATORS y = σ B/<B>
An estimator1 is defined, based on a comparison between the light produced by the muon and the light it would have produced if it was a minimum Ionizing muon:
An estimator2 is derived from estimator 1 and is
y = σ B/<B>
B=Number of Observed Photon/Number of Photons expected from MIM

14. HIT AND EVENT SELECTION
To overcome some of these problems partly
I choose only direct hits(-15ns to 75 ns)(less effected by ice properties)
Use hits with in 50m radius cylinder around the track(less scattered)
Require the event to have at least 6 direct hits(more direct hits means more information to study the fluctuations )
Criteria on Track length and chi square to improve reconstruction quality
Take only hits with amplitude greater 3.0 P.E for reconstruction.(No noise hits which will introduce some systematic fluctuations)

15. SIGNAL-BACKGROUND DISTRIBUTIONS
Singles
Multiples
Keep
These
Sigma/average
Sigma/average
Linear scale
Log scale
Done with Reconstructed track(Con Pandel)

16. SIGNAL-BACKGROUND DISTRIBUTIONS
Singles
Multiples
Keep
These
Sigma/average
Sigma/average
Lin scale
Log scale
Done with true track

17. SIGNAL-BACKGROUND DISTRIBUTIONS
Singles
When all hits are chosen
Notice what happens?
Any possible separation
Of signal and background
Through this parameter
is masked out by the fluctuations
Of ice properties
Multiples
Keep
These
Done with all hits (not just direct hits)

18. Correlation With Energy
Keep these
Keep These
Y VS Nhits(Energy estimator)
Y VS Nhits(Energy estimator)
Single muon Events
Multiple muon Events

19. Correlation With Muon Multiplicity
No great correlation with multiplicity and pass rate is approximately same at all multiplicities think why?
Depends on how the total energy is split among muons and sometimes muons end up with approximately same energies
Keep these
Y Vs Muon Multiplicity

20. Multiple Muon Event-1

21. Multiple Muon Event-2

22. Single Muon Event-1