What’s new in Calibrations

1. What’s new in Calibrations Kurt Woschnagg, UCB IceCube Collaboration Meeting, Ghent, October 10, 2007

2. Selected Calibration Topics • Waveform Calibration • DOMcalibrator [C. Roucelle] • Linearity/Saturation [S. Seunarine] • Relative DOM efficiency [H. Johannson] • Golden DOMs [M. Inaba] • Ice Properties • Dust logger update: deep ash layer found [R. Bay] • Standard Candle • Waveform analysis [M. Inaba] • Azimuthal asymmetry [J. Kiryluk] • New data (IC22+TWR) • Ice Shear • Interstring flasher data [KW] • Muon tomography [M. Olivo] • Inclinometers [R. Bay]

3. DOMcalibrator [Cécile Roucelle] : icecube/200709001

4. Dual t droop correction

5. General case

6. PMT linearity/saturation [Suruj Seunarine] Sketch of the method Measured V Expected V

7. PMT linearity/saturation DOMs have different saturation levels Will be parameterized → DB → DOMcalibrator In-situ flasher data

8. Relative DOM efficiency [Henrik Johansson] • Calculate average nphotons seen by a DOM from a • track at distance r (use well-reconstructed tracks) • Fit curve according to theory: exp(a-b·r) • Use <nphotons(r=0)> as measure • of DOM efficiency • Relate individual efficiencies to • mean efficiency

9. Relative DOM efficiency Two ways to estimate <nphotons> exp(a-b·r) nHits from FE Use track detection probability

10. Relative DOM efficiency Attempt to decouple ice effects Use average b, refit a Grouping by b, abs, z

11. Relative DOM efficiency ongoing…

12. Calibration of ROMEO with GDOM Outline [Kotoyo for Mina Inaba] Comparison DOMINANT+ROMEO Simulation PMT Calib. Data Glass+Gel Calib.Data DOM Calib.data • Challenging : • Large PhotoCathode area … Difficult to do overall ABSOLUTE calibration - Combine RELATIVE 2D measurement + small-area ABSOLUTE efficiency measurement ( )

13. Glass + Gel : Acceptance simulationNew transmittance and DOMINANT Outline • Transmittance of glass/gel is updated • Gel : available for all DOMS ! :) • Glass :still small sample(less than 10), need continuous monitoring New Acceptance Photon Acceptance Old DOMINANT Simulation Injection angle : 0deg (off-axis) Beam size : 8mm Beam location : center of PMT Parallel beam • Updated DOMINANT(Geant4) • New glass/gel transmit. • Harness, MB, FB, HV installed • Fresnel reflection ON Wavelength [nm]

14. Outline Golden DOM calibration Summary • We averaged available PMT calibration data • New Glass/Gel transmittance table is applied to DOMINANT simulation • The averaged absolute calibration of GDOM and Romeo + DOMINANT simulation with averaged calib data shows GOOD agreement over all wavelength range • New Romeo + DOMINANT simulation represents Stoyan’s In Water Angle Acceptance measurement

15. Dust logger update [Ryan Bay] First ash layer identified in instrumented volume: Corresponds to known 92,000 year old ash layer in Dome C core

16. Dust logging in the coming season

17. Standard Candle Basics Standard Candle I ~4ns @337nm Full intensity: (4.0±0.4)×1012/pulse 40” N2 laser 8”

18. Standard Candle I: waveform analysis [Aya for Mina Inaba] ATWD based total estimated Npe 100% ? First guess center of brightness COBy [m] COBx [m]

19. Standard Candle I: ATWD waveforms on str39 ATWD waveform of str39 DOM10 DOM11 DOM13 DOM15 DOM16 DOM18 DOM19 DOM20 DOM21 DOM25 DOM28 DOM30 MC Real

20. Standard Candle I: ATWD waveforms on str40 ATWD waveform of str40 DOM10 DOM11 DOM13 DOM15 DOM16 DOM17 DOM18 DOM25 DOM26 DOM28 DOM29 DOM30 MC Real

21. Standard Candle I: waveform analysis [Aya for Mina Inaba] Charge Ratio MC/Real 1690m 1910m 1920m 1680m SC

22. Standard Candle I: azimuthal asymmetry 1.30 [rad] 2.35 [rad] 3.45 [rad] 4.34 [rad] [Joanna Kiryluk] Standard Candle data SC DOM Number

23. Standard Candle I: 22-string data [Taboada/Filimonov] Data taken on September 18, 2007 • pDAQ IC22+TWR default configuration • PnF running • 7 filter wheel settings: 0.5%-100% • SC @ 1Hz, 2000 pulses/setting • 80 GBytes of raw data → SC filtering needed • Filtered data now in Data Warehouse: /data/exp/IceCube/2007/internal-system/ DebugData/1004/DebugData_SCData_Oct03.tar.gz • First pDAQ calibration data taken without detector downtime (as envisioned in the PDD) Milestone

24. Standard Candle I: 22-string data run 109337 run 109338 100% 50% 30% 10% 5%

25. Standard Candle I: 22-string data 5% setting, ~120 DOMs 100% setting, ~250 DOMs [AMANDA hits not shown]

26. How to take future Standard Candle data [I. Taboada] • Write a Standard Candle trigger • Base trigger on multiplicity, topology, timing • Create a pDAQ configuration that enables this trigger Otherwise configuration identical to default • Add a PnF filter that runs all the time to select events with a SC trigger No downtime and automatic filtering of SC data

27. Standard Candle II • To be deployed on string 55 (3rd of the season) • Between DOMs 42 and 43 • λprop (2150 m) ~38 m (SC-II) • λprop (1813 m) ~22 m (SC-I) • Pointing down (SC-I points up) • About 10 times brighter than SC-I • Filter wheel dynamic range: • SC-II: 1500 • SC-I: 120

28. Standard Candles 57 • Standard Candle II • deploy next season • pointing downward 63 64 55

29. Ice Flow and Shear flow model Three experimental approaches: 1. Using the three deep AMANDA strings 2. Muon tomography 3. Inclinometers http://wiki.icecube.wisc.edu/index.php/Ice_shear_measurement

30. Using the deep AMANDA strings ●48/57/58: recently deployed = ~vertical ●11/12/13: in the ice for >9 years

31. Pilot Runs 9/17 Dawn Williams Andreas Gross ~1700 m ~2000 m ~2300 m

32. What resolution can we achieve? Zoom in: 1 bin = 5 ns ≈ 1 m ~2300 m

33. muon tomography [Martino Olivo] Reconstruct tracks (include the DOM) Move DOM around (virtually), keep tracks stationary See how reco likelihood changes → Pandel function

34. muon tomography

35. muon tomography Under development…

36. Biaxial tiltmeter for constraining shear @ ~2430 m (on 3-4 strings 2007/08) [Ryan Bay] Special Devices breakout y x ~0.5°/year 3 strings meters per year Angular resolution: 0.01° Angular range: +/- 25° Operating temp: -40 to 85 °C Pressure vessel <2” I.D. (TBD)