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AMANDA
Lessons
Antarctic Muon And Neutrino Detector Array
South Pole, Summer 91/92Muon rates consistent with 25 m absorption length
Francis Halzen: The success of AMANDA stood on two pillars: the Amundsen Scott Station and Bruce Koci.
Bruce Koci ( 2006)
Deploy 4 strings at 800-1000 m depth
Sweden joins (Stockholm, Uppsala)
1 km
2 km
93/9440 m
CATASTROPHAL DELAY OF LIGHT !
AMANDA-A
Vostok Data
February 94: Amanda measures delay
March 94, Venice: G. Domogatsky points to Vostok results: it is scattering by remnant air bubbles !
April 94: tendency confirmed by Amanda data!
Vostok Data
February 94: Amanda measures delay
March 94, Venice: G. Domogatsky points to Vostok results: it is scattering by remnant air bubbles !
April 94: tendency confirmed by Amanda data!
February 94: Amanda measures delay
March 94, Venice: G. Domogatsky points to Vostok results: it is scattering by remant air bubbles !
April 94: tendency confirmed by Amanda data!
(delay time of light)
Vic Stenger (DUMAND): This is what Amanda sees
F.H.: and this is what DUMAND sees
1 km
2 km
Detector works very stable
Lousy scattering length ~ 1m, but: absorption length ~ 200 m !
40 m
Supernova detection
Can detect Supernovae with non-tracking detector!
No tracking. But photons survivefor long time
1995: DESY joins
1 km
2 km
95/96
no bubbles left scattering now dominated by dust
average scattering length ~ 25 m average absorption length >100 m down to wavelength of 337 nm !
60 m
AMANDA-B4
1 km
2 km
95/9660
m
AMANDA-B4... and: the first 2 neutrinos!
From ² fit to tailored Likelihood
Scattering
t
far track
close track
0 t
0 t
),,,,,( 0 scattabsiii distttfL
N
i i
ii tt
12
202 )(
1 km
2 km
96/97 AMANDA - B10
120 m
~300 neutrino events separated from 1997 data (~ 6 months) first physics intensive learning period on ice dust layers as well as hole ice
6 additional strings
1 km
2 km
IceCube will work !
120 m The EVA event
96/97 AMANDA - B10
1 km
2 km
120 m
96/97 AMANDA - B10
B10 skyplot published inNATURE, 2001
- 263 neutrino candidates- far from horizon!
1 km
2 km
3 strings instrumented between 1250 -2350 m study deep and shallow ice for future IceCube
Season 97/98
Ice properties vs. depth and wavelength
Scattering Absorption
bubbles
dustdust
ice
1 km
2 km
Lessons: - Need rigid long term tests - Selection of components- Lower HV
The gain-drop problem
1 km
2 km
total of 19 strings with 677 PMTs greatly enhanced sensitivity at horizon angular resolution ~ 2 degrees test IceCube technology (string 18)
200 m
Nearly horizontal
1999/2000 AMANDA-II
1 km
2 km
1999/2000 AMANDA-II
Alas! The stuck string
Lesson:- Fast is good. Too fast is bad.- More careful optimization of drilling regime !
1 km
2 km
SPASE air shower arrays
resolution Amanda-B10 ~ 3° absolute pointing < 1.5°
results in ~ 2.5° for upward moving muons
Use SPASE for pointing studies
Evolution of read-out strategy
- cost- robustness- dyn. range- easy calibration
- timing- dyn. range- no x-talk
Test of IC3
technology
dAOM versus DOM
copper cable digital
optical fibre analogbut a) HV in OM b) PM-anode amplifier LED (dynamic range!)
Lesson: take the best and then collaborate!
in ice: DOM (Digital Optical Module): LBNL
at surface: DOR (DOM Receiver Card): DESY
AMANDA
= 30 x SuperK, MACRO
(AMANDA = 1/30 IceCube)
AMANDA 7 years: The results
6595 neutrinos up to record energy of 200 TeV
Record limits on fluxes for cosmic neutrinos (diffuse, point sources, GRB)
Record limits on indirect dark matter search, magnetic monopoles, tests of Lorentz invariance
Monitoring the galaxy for supernova bursts Spectrum and composition of cosmic rays
Challenges
The bubble problemAmanda: to be or not to be
The ice challenge
Kurt
Reconstructing tracks
The gain drop problem
The stuck string
Finding the best technology
Without AMANDA, we would not havesolved – even not recognized – theseissues!
