AMANDA and IceCube neutrino telescopes at the South Pole Per Olof Hulth Stockholm University
Members of the AMANDA SU group Senior members Senior members Christian Bohm Christian Bohm Per Olof Hulth Per Olof Hulth Klas Hultqvist Klas Hultqvist Christian Walck Christian Walck Forskarassistent Forskarassistent Stephan Hundertmark Stephan Hundertmark Resarch students Resarch students Thomas Burgess Thomas Burgess Patrik Ekström (Wuppertal) Patrik Ekström (Wuppertal) Yulia Minaeva Yulia Minaeva Julio Rodriguez Martino Julio Rodriguez Martino Christin Wiedemann Christin Wiedemann Electronic engenieer Electronic engenieer Lars Thollander Lars Thollander
Scientific goal Detect High Energy cosmic neutrinos by using the ice sheet at The South Pole as a target. Detect High Energy cosmic neutrinos by using the ice sheet at The South Pole as a target. Method: Method: Detect the emitted Cherenkov light from neutrino induced interactions in the ice.
Activities Mainly analysis and software development Mainly analysis and software development Preamplifiers designed and built in Stockholm (SWAMPS) Preamplifiers designed and built in Stockholm (SWAMPS)
Short summary of neutrinos for pedestrians There are three different “families” of leptons There are three different “families” of leptons Electron neutrino ( e ) and the electron (e - ) Electron neutrino ( e ) and the electron (e - ) Muon neutrino ( ) and the muon Muon neutrino ( ) and the muon Tau neutrino ( ) and the tau Tau neutrino ( ) and the tau
Neutrino interaction The muon can travel several km in e.g. ice < 1 degree
Cherenkov radiation cos n v/c, n= refraction index A charged particle moving with the speed of light in the medium will generate a shock wave of light
South Pole Dark sector AMANDA IceCube Dome Skiway
neutrino myon
neutrino myon 10 6 muons from cosmic rays per muon from neutrinos !!!! Select only muons from below!!!! Except for high Energies”
Hot water heaters -55 C -20 C m -50 m 1400 m-42C
Photomultipliers: Hamamatsu 20 cm 14 dynodes Gain 10 9
AMANDA electronics Three different cable types ( m) Three different cable types ( m) Strings 1-4 coax cable, rise time 250 ns Strings 1-4 coax cable, rise time 250 ns Strings 5-10 twisted pair rise time, ns Strings 5-10 twisted pair rise time, ns Strings twisted pair rise time ns Strings twisted pair rise time ns Analog signal at surface about 1-10 mV Analog signal at surface about 1-10 mV Amplified 100 times by Stockholm “SWAMP” (Lars Thollander) Amplified 100 times by Stockholm “SWAMP” (Lars Thollander)
Technical requirements Absolute timing <7 ns from any OM Absolute timing <7 ns from any OM Geometrical position uncertainty < 1m Geometrical position uncertainty < 1m Electronic in ice should stand -50 C Electronic in ice should stand -50 C Low noise Low noise
Building AMANDA: The Optical Module and the String
cost - cost - robustness - dynamic range range timing - timing - dyn. range - no x-talk - easy calibration calibration Evolution of read-out strategy Strings 1-10 Strings 11-17,19 String 18
New Project IceCube Increase volume to 1 km 3 Increase volume to 1 km 3 80 strings with 60 modules each 80 strings with 60 modules each Photomultiplier 25 cm (10 inch) 10 dynodes (preliminary Hamamatsu) Photomultiplier 25 cm (10 inch) 10 dynodes (preliminary Hamamatsu) Air shower detector on top (IceTop) Air shower detector on top (IceTop) Transport drill to Pole 03/04 Transport drill to Pole 03/04 First 1-7 strings in 04/05 First 1-7 strings in 04/05
IceCube 80 Strings 4800 PMT 1400 m 2400 m AMANDA South Pole IceTop Skiway
IceCube:Top View AMANDA SPASE-2 South Pole Dome Skiway 100 m Grid North Counting House 80 strings 60 modules/string Volume 1 km 3 Depth m
µ-events in IceCube 1 km E µ =10 TeV E µ =6 PeV AMANDA-II Measure energy by counting the number of fired PMT. (This is a very simple but robust method)
1. Digital Optical Module 1. Digital Optical Module Self-triggers on each pulse Self-triggers on each pulse Captures waveforms Captures waveforms Time-stamps each pulse Time-stamps each pulse Digitizes waveforms Digitizes waveforms Performs feature extraction Performs feature extraction Buffers data Buffers data Responds to Surface DAQ Responds to Surface DAQ Set PMT HV, threshold, etc Set PMT HV, threshold, etc Noise rate in situ: ≤500 Hz Noise rate in situ: ≤500 Hz 33 cm DOM
IceCube String 1400 m 2400 m OM Spacing: 17 m
Experimental Requirements IceCube Time resolution:<5 ns rms Time resolution:<5 ns rms Waveform capture: Waveform capture: >250 MHz - for first 500 ns ~40 MHz - for 5000 ns Dynamic Range: Dynamic Range: >200 PE / 15 ns >2000 PE / 5000 ns Dead-time:< 1% Dead-time:< 1% OM noise rate:< 500 Hz ( 40 K in glass sphere) OM noise rate:< 500 Hz ( 40 K in glass sphere)
2. DAQ Network architectu re 2. DAQ Network architectu re
In-Door deployment
ENGINEERING AND INSTRUMENTATION - UNIVERSITY OF WISCONSIN MADISON Hose Winch for the Ice Cube Project
Receiving drum weldment
POSITION OF DRILL (30HOUR ANALYSIS)