1. IceCube

2. IceCube predecessor:
AMANDA (Antarctic Muon And Neutrino Detector Array)
Completed in year 2000
From 2005 on: Amanda will merge with its successor experiment IceCube (currently in construction)

3. New types of telescopes using high-energy neutrinos
Search of colliding galaxies, exploding stars, gamma-ray bursts and dark matter
New types of telescopes using high-energy neutrinos
Neutrinos= ideal astronomical messangers: Are able to leave compact sources and travel unhindered from distant reaches and violent astrophysical phenomena p  e
cosmic rays +
neutrinos
gamma-rays 0 + n

4. Travel in straight line (≠protons)
Transparent Universe (≠γ)
UHE neutrinos are a new observation channel for studying astrophysical objects and the highest energy phenomena producing UHE cosmic rays

5. Using large quantities of ice as neutrino detector
Cross section for neutrino interaction is very small. So, giant detectors are needed
Using large quantities of ice as neutrino detector
AMANDA / IceCube
Main Goal:
IceCube will search for extra-terrestrial neutrinos in the high-energy range (1011eV-1019eV) , from sources such as active galaxies, or gamma-ray bursts
(supernova explosions, gamma-ray bursts, black holes or other extra-galactic events)
One hopes to find some information about the physical processes associated with those high energies. As well as to reveal (parts of) the nature of Dark Matter.

6. Advantage of ice (over water):
Clean, transparent material
Lack of radioactivity
Absence of biological activity
Low temperatures reduce dark noise rates
Stable ground

7. Detection Method: Neutrino collides with atom of ice
=> produces muon
In ultra-transparent ice, muon radiates Cherenkov light and Cherenkov photons are detected by array of photomultiplier tubes
Tracks are reconstructed of photon arrival times
Geometry: relative OM position known within 0.5 m, absolute depth to within 1m
+ N X n m m
Optical module
15m

8. Neutrinos are measured from below (neutrino separation: upward going tracks)

9. The IceCube Collaboration (formerly known as AMANDA)
Alabama University, USA
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
IAS, Princeton, USA
University of Wisconsin-Madison, USA
University of Wisconsin-River Falls, USA
LBNL, Berkeley, USA
University of Kansas, USA
Southern University and A&M College, Baton Rouge, USA
The IceCube Collaboration
(formerly known as AMANDA)
USA (14)
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
Universität Wuppertal, Germany
MPI Heidelberg, Germany
Uppsala University, Sweden
Stockholm University, Sweden
Imperial College, London, UK
Oxford University, UK
Utrecht University, Netherlands
ANTARCTICA

11. The IceCube array in the deep ice
The IceCube array in the deep ice. The dark cylinder is the AMANDA detector, incorporated into IceCube.

12. IceTop (= Surface component of IceCube):
80 IceTop stations at the surface with 2 tanks per station.
Air shower array to study cosmic ray composition. Further, coincident events between IceTop and the in-Ice detector provide useful cross-checks of the detector performance
Inside an IceTop tank

13. AMANDA IceCube
~677 photomultiplier tubes (PMTs) arranged on 19 strings
Placed between 1500m and 2000m
Detector area
500m x 200m
4800 photomultiplier tubes (PMTs) on 80 strings (60 on each string)
Placed at depths between 1450m-2450m
1km3 of ice as detector

14. How it works:

15. Drilling: Using a hot water drill (drill holes are more than 2
Drilling: Using a hot water drill (drill holes are more than 2.5 km deep)
Photomultiplier tubes record (PMT) Cherenkov radiation
Each photomultiplier is enclosed in a transparent pressure sphere, a digital optical module (DOM) which also contains a digitally controlled high voltage supply to power the photomultiplier, an analog transient waveform digitizer and LED flashers
Signals digitized in the DOM are communicated to the IceCubeLab at the surface for data acquisition and data analysis
Data is transmitted via satellite from the South Pole to data storage facilities for more data analysis effort

16. Drilling and deployment:
1st step: Drill though the firn layer (compacted snow, 50m) down to the actual ice. Circulate and re-circulate hot water through the firn drill
2nd step: Drilling by using hot water. Pumping hot water down the ice hole made by firn drill, results in melting the ice. Cooler water flowes back up, is reheated and reused
Drill water comprises a total of 15 buildings that host hot water heaters, generators, pumps and storage tanks in temporary camps
Strings of modules are deployed into holes
Takes ~18 h to deploy a string

17. Schematic view of IceCube DOM
Digital optical Module= fundamental detector element
Consists of Photomultiplier Tube (PMT) and a suite of electronics board assemblies contained within 35cm diameter glass pressure housing
Are downward facing
Is able to digitize and time-stamp the photonic signal internally and transmit packetized digital data to the surface
First demonstrated in AMANDA: each DOM allowes to operate as a complete and autonomous data acquisition system
Derives its internal power (incl. PMT hight voltage) by the cable
Within a DOM, data acquisition is initiated when the PMT signal exceeds a programmable threshold
Will operate for at least 15 years
Schematic view of IceCube DOM

18. IceCube array shown in relation to the drill camp and the bedrock beneath
IceCube DOM array and
a Cerenkov cone of
blue light passing throug

19. Event illustration in the array
The path of the light is reconstructed using the times of detection. The earliest hits are displayed in red and subsequent ones in orange, yellow, green

20. Animated IceCube Event:

21. AMANDA effectiv area (30,000-50,000m2)
Detected muons from the Northern Hemisphere that penetrated the Earth and exit through Antarctica:
AMANDA-II has nearly uniform response over all zenith angles.
=> Sensitivity independent of direction

22. Search for point sources of neutrinos
data sample collected by the AMANDA-II detector (live-time 807 days)
Search for point sources of high energy neutrinos
No obvious clustering.
No evidence of a significant flux excess above the background
Sky plot: Neutrino flux integrated above 10GeV in equitorial coordinates
3329 neutrinos from northern hemisphere
3438 neutrinos expected from atmosphere

23. Steady Point Source Search
Search for excess events from the direction of known gamma-ray emitters
=> No statistically significant excess found from 33 objects

24. Future: January 2008 Construction Status :
40 Strings and 80 Tanks deployed.
Set of measurements performed to confirm the design of the detector and check its performance
March 2010:
Full Operational Capability.
September 2010:
Complete IceCube Construction Project.
January 2011:
70 Strings and 160 Tanks deployed.
Detector will be operated 20 years.

25. Summary: AMANDA has searched the sky for high energy neutrinos
So far no source or no diffuse flux of high energy extraterrestrial neutrinos has been identified
More analysis under way
IceCubes first string with 60 OMs was deployed in January 2005
All OMs communicate and deliver data as expected
Hope that km- scale experiment (IceCube) will be able to increase the detection sensitivity

26. Wisconsin Research Journal: Video