1. Comparison between Aasim and Calibob
Motivation:
- two different MC to extract opticalproperties
- estimate systematic uncertainty
Comparison for MC inputs:
- with default optical properties
- with no scattering
Thanks to Stephan and Aart for their help

2. Input Aasim and Calibob simulation have:
L_abs=50 m, L_scatt=50 m, eta = 0.17
Run=58120
No efficiency corrections
Remark:
Calibob based on KM3
Aasim without simulation of electronics

3. Comparison Compare MCs along same line
Following histogram have same integral
Check line 2 (similar results for other lines)
Compare
- higher part of the line (photo electron regime) - lower part of the line

4. Line 2 (each om with interval [-0, 300] ns)
Black: calibob
Red: aasim
Tails seem to agree
Scattering seems ok
Floor 12
Floor 13
Floor 14
Floor 15
Floor 16
Floor 17

5. Log scale: Line 2 (each om with interval [-0, 300] ns)
Black: calibob
Red: aasim
Floor 12
Floor 13
Floor 14
Floor 15
Floor 16
Floor 17

6. Log scale: Line 2 (each om with interval [-0, 300] ns)
Black: calibob
Red: aasim
Floor 12
Floor 13
Floor 14
Floor 15
Floor 16
Floor 17

7. Line 2 far photo-electronregion (each bin is the integral of a PMT)
PMT get different amount of light
- scattering ?
- angular acceptance ?
- binning ?
- shadowing ?
- etc. ?
Aasim more pronounced variations
Black: calibob
Red: aasim
Floor 12
Floor 13
Floor 14
Floor 15
Floor 16
Floor 17

8. Line 2 near (each bin is the integral of a PMT)
Near OMs
Histogram missing:
Floor 7 OM 0
Floor 10 OM 0
Floor 5
Floor 6
Floor 7
Floor 8
Floor 9
Floor 10
Floor 11

9. Input: No scattering Aasim/Calibob simulation have no scattring:
L_abs=50 m, L_scatt>10^5m, eta = 0.17
Run=58120
No efficiency corrections

10. No Scattering: Line 2 fare (each bin is the integral of a PMT)
Black: calibob
Red: aasim
Smaller difference
=>difference generated
from scattering
Stephan already knows
Floor 12
Floor 13
Floor 14
Floor 15
Floor 16
Floor 17

11. No scattering: Line 2 near (each bin is the integral of a PMT)
Black: calibob
Red: aasim
For floors which are near OB
differences in integral even for
MCs without scattering
=> some other effects also play
a role
Near OMs
Histogram missing:
Floor 7 OM 0
Floor 10 OM 0
Floor 5
Floor 6
Floor 7
Floor 8
Floor 9
Floor 10
Floor 11

12. Conclusion
Aasim and Calibob disagree, but we can use it as uncertainty of our systematic
Important check to do:
Can we find the correct input optical properties when using e.g. Calibob runs as MC templates and an Aasim run as unknown data?
If yes we have enough sensitivity to extract optical properties

13. Find best Calibob run for Aasim run (aasim as data)
Input
Scatt= 50 m
Abs = 50 m
Minimum at
Scatt=50 m
Abs =45 m
This is valid for
Floors between
Floor 12 and Floor 20
Method has enough
sensitivity to
distinguish optical
properties

14. Data vs MC

15. Data vs Calibob Super-Super-Histogram (all lines except OB line) 180 PMTs

16. Chi2 for all lines at same time 180 PMTs

17. Old way
Chi2 is sum of 11 lines
Chi2/11

19. because of ARS token ring effect, select photoelectron region
OM selection
Some OMs are rejected:
OMs too close to the OB Floor > 13
because of ARS token ring effect, select photoelectron region
OMs too far away Floor < 21
because of missing statistics
OMs whose efficiency ε < or ε > 1.5
because of large extrapolation
Backwards looking OMs
because of PMT acceptance uncertainty
OMs very inclined
Led emission uncertainty
OMs after visual inspection of their distributions
This selection can introduce a possible bias

20. All cuts 180 PMTs Numbers give Chi2/ndf
Minimum seems to be slightly flatter (45 – 60 m)

21. Include backward looking and very inclined 242 PMTs
Minimum stable

22. Include also visual inspection rejected 263 PMTs
Minimum stable

23. Increase photo electron region cut (0.35->0.55) 324 PMTs
Minimum stable at m

24. Increase photo electron region cut (0.35->0.75) 349 PMTs
Minimum stable

25. Decrease photo electron region cut (0.35->0.25) 235 PMTs
Minimum flat and shifts

26. Decrease photo electron region cut (0.35->0.15) 192 PMTs
Minimum shifts

27. Conclusion How to get to the final result?
In principle we have two different MC.
We will never get good chi2. In reality they are very bad.
Should we compare Aasim with data?