1. IceCube Neutrino Telescope Astroparticle Physics at the South Pole
Brendan Fox
Pennsylvania State University
for the IceCube Collaboration
VLVNT08 - Very Large Volume Neutrino Telescopes
Toulon, France

2. The IceCube Collaboration
Bartol Research Institute, Delaware, USA
Pennsylvania State University, USA
UC Berkeley, USA
UC Irvine, USA
Clark-Atlanta University, USA
University of Alaska, Anchorage, USA
Univ. of Maryland, USA
29 institutions
~250 people
University of Wisconsin-Madison, USA
University of Wisconsin-River Falls, USA
LBNL, Berkeley, USA
Southern University and A&M College, Baton Rouge, USA
USA (11)
Japan
Europe (15)
Chiba University, Japan
University of Canterbury, Christchurch, NZ
New Zealand
Universite Libre de Bruxelles, Belgium
Vrije Universiteit Brussel, Belgium
Université de Mons-Hainaut, Belgium
Universiteit Gent, Belgium
Humboldt Universität, Germany
Universität Mainz, Germany
DESY Zeuthen, Germany
Universität Dortmund, Germany
ANTARCTICA
Universität Wuppertal, Germany
MPI Heidelberg, Germany
RWTH Aachen
Uppsala University, Sweden
Stockholm University, Sweden
Oxford University, UK
Utrecht University, Netherlands
Amundsen-Scott Station

3. Detecting Neutrinos In Ice
Phototubes 
Muon neutrino
Electron neutrino
Tau neutrino
Track: + increased detection volume
Cascade: - must be in detector
Hybrid: - must be in detector
+  points along , i.e. to source
-  background (brems’ng)
- need E>o(1000 TeV)
- cosmic ray  background
- limited pointing capability
+ nil background
- energy measurement “okay”
+ good energy measurement
+ pointing capability
+ best energy measurement
(also includes NC ,)

4. Digital Optical Module (DOM)
IceCube-AMANDA
AMANDA
Eiffel Tower
Svenska Dagbladet
Digital Optical Module (DOM)
currently
instrumented
IceTop
- ICECUBE : 4800 DOMs on 80 strings
ICETOP : 160 Ice-Cherenkov tank surface
array (IceTop)
- AMANDA: 677 OMs surrounded by IceCube

5. IceCube Digital Optical Module
Low intrinsic noise ~ 500 Hz
Fast digitization 30 ms/channel
Waveform: 4 channels/128 sample
Low power consumption 5 W per DOM
Up to 12 ms combined waveform length
Variable sampling speed: MHz
Up to p.e./10 ns charge resolution

6. IceCube Digital Optical Module

7. DOM Final Acceptance Testing
freezer
~60 DOMs at time
3 identical setups at UW-Madison (USA)
1 setup at DESY-Zeuthen (Germany)
1 setup at Uppsala University (Sweden)

8. DOMCal Summary for FAT22 Budweiser-TP4Y0031
1260 Volts
1340 Volts
Gain vs. HV Fit
1e7
DOMCal Summary for FAT22 Budweiser-TP4Y0031
1.6pC
Charge (pC) HV
Most PMTs achieve
1e7 at Volts
• Require 5e7 at <2kV

9. Time Resolution Test
Laser occupancy ~ laser trigger times recorded
in dedicated “Sync DOM”
PMT signal recorded in DOM 100,000 synchronized hits sampling time 3.5nsec pulse height digitizer 0.1mV/count
Time computed from leading edge (50% of pulse maximum)
Resolution 2-3nsec includes DAQ time slewing relative to Sync DOM

10. Dark rate monitoring ~120 hours checking for: Average Rate 2-3kHz
Temp (°C)
–35°C
–10°C
5e7
Dark rate monitoring
~120 hours checking for:
Average Rate 2-3kHz
includes non-PMT contributions
will be 650Hz in ice (or 300Hz without double- counting time-correlated noise)
No instabilities

11. Construction Plan Overview
08-09
09-10
IC-40 DEPLOYED
AMANDA
… drilling/deployment plans for the season being discussed

12. Schematic of Hot Water Drilling

14. String Deployment

15. Season
… 18 strings deployed!

16. String 39 two-week freeze-in movie
Commissioning
String 39 two-week freeze-in movie

17. Commissioning 76
528
820
1136

18. DOM Survivability 76 DOMs 589 DOMs 1390 DOMs 2515 DOMs
66-33 “New_York” and “Dou_Mu” go high current
39-61 “Hydrogen” PMT breaks
54-47 “Garbanzo_bean” stops communicating
39-22 “Liljeholmen” stops communicating properly
39-21 “Aspudden” slows down
30-60 “Rowan” stops communicating

19. DOM-to-DOM Synchronization
RAPCAL: Sync each DOM to GPS time

20. Initial Timing Verification

dom 10
17m
dom 11
string 76

21. Initial Timing Verification

Means
Sigmas
… timing of all DOMs within spec (<3 ns)

22. Timing Verification With Muons
Cherenkov
Photons
 track
Emission on the
Cherenkov
Cone
string 49

23. Long-Term Stability of Timing
track position of leading edge on monthly basis …
… timing stable over IC-22 data-taking period

24. Initial String Geometry

25. String Geometry
- z check

26. String Geometry
- z check
For string 64, the stage 1 depth was a bit of guess since
the pressure sensor broken.

27. String Geometry - (x,y) check

Select well reconstructed muon tracks
Vary (x,y) of DOM … look at the log-likelihood -vs- (x,y)
Minimium will be where the DOM is situated
MC studies still underway … technique looks promising

28. Readout Scheme

29. Detector Monitoring Snapshot

30. Neutrinos in IC-9 (2006) RESULT
Online filtering at Pole to isolate sample of “good” up-going candidates
Transfer this sample by satellite to North
More refined analysis …
… Log-likelihood reconstruction, etc.
… apply additional quality cuts, etc. to
gain more down-going muon rejection
Ratio of data to simulation:
At selected cut strength of 10:
234 up-going  in live-days of data
(purity of neutrino sample > 95%)
Mis-reconstructed
atmospheric muons
RESULT
J. Pretz, Ph.D. thesis (Maryland)
[DRUM ]

31. Neutrinos in IC-9 (2006) ZENITH AZIMUTH t ~ 90-110° … muon background
peaks in  artifact of the IC-9 string
configuration

32. Prospects for IC-22 … IC-40 … (Integrated Exposure)
“Actual”
Graph shows cumulative km3·yr of exposure × volume
1 km3·yr reached 2 years before detector is completed
Close to 4 km3·yr at the beginning of 1st year of full array operation.
NOTE: not adjusted for actual

33. Upcoming Season Plans 1996-2001: AMANDA 2004-05: 1 string 2005-06: 8
: 13
12 planned
: 18
14 planned
: 16+
: 16+
: 7+
09-10
08-09

34. String Layout Options DEEP CORE UHE STRINGS Preliminary design
Olaf Schulz
Preliminary design
UHE
STRINGS

35. Conclusions Drilling/deployment of IceCube strings is going well
Deployment of IceTop stations also on target (40 stations deployed)
IceCube components (DOMs/daq/triggers/filter/etc.) up and going
IceCube is working as expected
… first physics results from IC-22 (318 95% uptime)
… IC-40 data-taking started April 1, 2008
IceTop-40 is working too
… tank/station performance as per specs
… first physics physics from IC-22 being prepared now
AMANDA integrated into IceCube
… low energy results improved by using IceCube as veto
In the future,
- Low energy core planned … first string to be deployed 08-09
- UHE arrangement of final strings underway
… Elisa Resconi discussed the physics expected from IceCube + these extensions.

36. BACKUP SLIDES

37. } LC IceCube Triggering InIce:4 3 5 2 1
InIce:
- Local coincidence between neighboring modules
(variable time window: presently = 1 us)
On the surface:
- require NDOMs  8 within 5 us window
Form event from all “hits” within ±8 us of trigger
} LC

38. Ice Properties Bubbles at higher depth dust layers
Scattering
Absorption
Bubbles at higher depth
dust layers
Average optical parameters:
abs ~ nm
sca ~ nm