AMANDA and IceCube neutrino telescopes at the South Pole

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AMANDA and IceCube neutrino telescopes at the
South Pole

• Per Olof Hulth
• Stockholm University

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Members of the AMANDA SU group

• Senior members
• Christian Bohm
• Per Olof Hulth
• Klas Hultqvist
• Christian Walck
• Forskarassistent
• Stephan Hundertmark
• Resarch students
• Thomas Burgess
• Patrik Ekström (Wuppertal)
• Yulia Minaeva
• Julio Rodriguez Martino
• Christin Wiedemann
• Electronic engenieer
• Lars Thollander

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Scientific goal

• Detect High Energy cosmic neutrinos by using the
  ice sheet at The South Pole as a target.
• Method
• Detect the emitted Cherenkov light from neutrino
  induced interactions in the ice.

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Activities

• Mainly analysis and software development
• Preamplifiers designed and built in Stockholm
  (SWAMPS)

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Short summary of neutrinos for pedestrians

• There are three different families of leptons
• Electron neutrino (?e) and the electron (e-)
• Muon neutrino (??) and the muon (?-)
• Tau neutrino (??) and the tau (?-)

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Neutrino interaction
??
??
lt 1 degree
The muon can travel several km in e.g. ice
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Cherenkov radiation
A charged particle moving with the speed of light
in the medium will generate a shock wave of light
q
cosq 1/(nb) b v/c, n refraction index
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South Pole
Dark sector
Skiway
AMANDA
Dome
IceCube
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myon
neutrino
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106 muons from cosmic rays per muon from
neutrinos !!!!
myon
Select only muons from below!!!! Except for
high Energies
neutrino
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Hot water heaters
-50 m
-55 C
1400 m
-42C
-20 C
-2400 m
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Photomultipliers Hamamatsu 20 cm 14 dynodes Gain
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AMANDA electronics

• Three different cable types (2400 -2600 m)
• Strings 1-4 coax cable, rise time 250 ns
• Strings 5-10 twisted pair rise time, 50-70 ns
• Strings 11-19 twisted pair rise time 100-150 ns
• Analog signal at surface about 1-10 mV
• Amplified 100 times by Stockholm
  SWAMP (Lars Thollander)

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Technical requirements

• Absolute timing lt7 ns from any OM
• Geometrical position uncertainty lt 1m
• Electronic in ice should stand -50 C
• Low noise

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Building AMANDA The Optical Module and the String
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Evolution of read-out strategy
Strings 1-10 Strings 11-17,19
String 18
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New Project IceCube

• Increase volume to 1 km3
• 80 strings with 60 modules each
• Photomultiplier 25 cm (10 inch) 10 dynodes
  (preliminary Hamamatsu)
• Air shower detector on top (IceTop)
• Transport drill to Pole 03/04
• First 1-7 strings in 04/05

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IceTop
AMANDA
South Pole
IceCube
Skiway
80 Strings 4800 PMT
1400 m
2400 m
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IceCubeTop View
80 strings 60 modules/string Volume 1 km3 Depth
1400-2400 m
Counting House
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µ-events in IceCube
Eµ6 PeV
Eµ10 TeV
AMANDA-II
1 km
Measure energy by counting the number of fired
PMT. (This is a very simple but robust method)
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1. Digital Optical Module

• Self-triggers on each pulse
• Captures waveforms
• Time-stamps each pulse
• Digitizes waveforms
• Performs feature extraction
• Buffers data
• Responds to Surface DAQ
• Set PMT HV, threshold, etc
• Noise rate in situ 500 Hz

DOM
33 cm
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IceCube String
1400 m
OM Spacing 17 m
2400 m
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Experimental Requirements IceCube

• Time resolution lt5 ns rms
• Waveform capture
• gt250 MHz - for first 500 ns
• 40 MHz - for 5000 ns
• Dynamic Range
• gt200 PE / 15 ns
• gt2000 PE / 5000 ns
• Dead-time lt 1
• OM noise rate lt 500 Hz (40K in glass sphere)

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2. DAQ Network architecture
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In-Door deployment
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Hose Winch for the Ice Cube Project
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Receiving drum weldment
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POSITION OF DRILL(30HOUR ANALYSIS)