The evolution of high energy neutrino
telescopes
Christian Spiering
DESY
The evolution of high energy neutrino
telescopes
…a long march
which has not
yet reached
its end.
underground
optical:
- deep water
- deep ice
- air showers
- radio
- acoustics
underground
optical:
- deep water
- deep ice
- air showers
- radio
- acoustics
This talk will essentially address
the optical telescopes deep under
water and in ice. See the written
version for the high-energy frontier
and the corrersponding techniques
Ann.Rev.Nucl.Sci
10 (1960) 63
Ann.Rev.Nucl.Sci
10 (1960) 1
Moisej Markov
M.Markov,
Bruno Pontecorvo
1960:
„We propose to install detectors deep in a lake or in the sea and
to determine the direction of charged particles with the help
of Cherenkov radiation“ Proc. 1960 ICHEP, Rochester, p. 578.
Central interest: cross sections, W-mass
… one of the main motivations for Reines‘ South Africa detector, the Kolar Gold
Field Detector (India) and the Baksan scintillation detector. Early sixties: does
the neutrino cross section saturate beyond 1 GeV (i.e. one would never measure
atm. neutrinos with energies higher than a few GeV). The question was relaxed in
the mid seventies:
First measurement of atmospheric
neutrinos
Beside several ideas like e.g.
 H. Uberall and C. Cowan, 1965
CERN Conf. on Experimental
Neutrino Physics, p. 231
– Downward looking PM observing a
10 m thick water target, „possibly in
ocean or a lake“
 V. Bogatyrev, Yad.Fiz 13 (1971) 336
– Three detectors each 107 tons of distilled
water a several km depth, widely spaced
 SN triangulation
in 1965 detection of nearly
horizontal atmospheric neutrinos
by F. Reines in a South African
Gold mine.
DUMAND
See also: A.Roberts: The birth of high-energy neutrino
astronomy: a personal history of the DUMAND project,
Rev. Mod. Phys. 64 (1992) 259.
 1973 ICRC, Reines, Learned, Shapiro, Zatsepin, Miyake:
a deep water detector to clarify puzzles in muon depth-intensity
curves
 Puzzles faded away, but there remained the awareness that such
a detector could also work as neutrino detector
 The name: DUMAND (Deep Underwater Muon And Neutrino
Detector), proposed by Fred Reines
 1975: First DUMAND Workshop in Washington State College
 DUMAND Steering Committee, chaied by F.Reines, J. Learned, .
A.Roberts
Principle and capabilities
 Angular resolution of
1° possible
 astrononomy
 Energy resolution for
muons is 50% at
best, for 1 km track
length


The DUMAND Workshops
 An unbelievable source of basic ideas
(including crazy ones which are sometimes the most exciting)





1976 Honolulu
1978 Scripps
1979 Khabarovsk/Baikal
1978 Honolulu
Plus dedicated workshops on deployment, acoustic
detection, signal procressing and ocean
engineering
Which physics?
 UNDINE: UNderwater Detection of Interstellar Neutrino
Emission
– i.e. Supernova  too rarely to optimize an ocean detector for it ( IMB)
 ATHENE: ATmospheric High-Energy Neutrino Experiment
– Better with underground experiments
A. Roberts:
 UNICORN: UNderwater Interstellar COsmic Ray Neutrinos
– The high energy option
– preferred option, but: how large are the fluxes ?
–  think as big as possible !
1978: 1.26 km³
22,698 OMs
1980: 0.60 km³
6,615 OMs
1982: 0.015 km³
756 OMs
1988:
0.002 km³
216 OMs
DUMAND-II
Financial and technological reality !
DUMAND-II (The Octagon)





9 strings
216 OMs
100 diameter, 240 m height
Depth of bottom: 4.8 km
Lowest OM 100 m above
bottom
p  p    ....
   
 e  e  
p  n

or
  
 p
0
  
Point sources, DUMAND-II (0.002 km³)
expectations in the eighties
!!!
Note: in 1989, the only proven TeV  source was the Crab SNR!
With these assumptions, a km³ detector would have discovered 5-50 (worst scenario)
up to several ten thousand events (best scenario) per source
Diffuse sources, DUMAND-II (0.002 km³)
expectations in the eighties
Technology boosts
 Optical fibers with < 12 db
attenuation over 40-km length
and data rates of hundreds of
MBaud (Nobel prize 2009!)
 Appearance of
16“ Hamamatsu PMT
JOM
Japanese Optical Module
 Appearance of
14“ „smart“ Philips PMT
EOM
European Optical Module
1987: The SPS
„Short Prototype String“
 1982-87:
a series of 14 cruises,
with two lost strings
 1987: success !
– depth-intensity curve
– angular distributions
– attenuation lenght (4722 m)
DUMAND after the SPS:





1989: HEPAP supports DUMAND-II
1990: DOE allocates funds for DUMAND-II
Further financial cuts  TRIAD (3 strings)
1993: shore cable laid
December 1993: deployment of first string and
connection to junction box. Failure after several
hours
 1995: DUMAND project is terminated
Russia
 Very active during early DUMAND workshops
(Chudakov, Berezinsky, Bezrukov, Zhelesnykh, Petrukhin)
 Kicked out of DUMAND after Russian Afghanistan invasion
A. Roberts:
 1980: Chudakov proposes exploration of Lake Baikal as
possible site for a neutrino telescope
 1981: start of site investigations at Lake Baikal
(Domogatksy, Bezrukov)
 Exploration of Atlantic, Black Sea, Indian Ocean, Pacific and
Mediterranean sites (Zheleznyk, Petrukhin)

A. Roberts: „Communication among these groups is not very good“
The Lake BAIKAL experiment
Bezrukov, Domogatsky, Berezinsky, Zatsepin
G. Domogatsky




Largest fresh water reservoir in the world
Deepest Lake (1.7 km)
1981: first site explorations & R&D
Choosen site 3.6 km from shore, 1.3 km
depth
Ice as a natural deployment platform
… and its mis-interpretation:
A. Roberts:
Lake Baikal: the eighties
 1984: first stationary string
– Muon flux measurement
 1986: second stationary string
(Girlyanda 86)
– Limits on GUT
magnetic monopoles
 All that with 15-cm
flat-window PMT FEU-49
 Development of a Russian
smart phototube (Quasar)
Towards NT-200
J. Learned to C.Spiering:

1988: Germany joins

1989/90: design of NT-200

1993 + 1994: NT-36
- 18 channels at 3 strings
- first underwater array
- first 2 neutrino candidates

1995: NT-72
- 38 channels at 4 strings

1996: NT-96
- 48 channels at 4 strings
- clear neutrinos

1998: NT-200
- 96 channels at 8 strings
„Congratulations for winning
the 3-string race!“
(NT-36 vs TRIAD vs AMANDA)
4-string stage (1996)
NT-200
2 PMTs in coincidence
to surpress background
NT-200
NT200 results
396  candidates
 Atmospheric neutrinos
 WIMP search
 Diffuse neutrino fluxes
 Skymap
 GRB coincidences
 Magnetic monopoles
NT200+
For searches of diffuse neutrino fluxes, the small NT200
could compete with the much larger Amanda by monitoring
a large volume below the detector. NT200+ fences this volume.
construction
1993-1998
NT200
NT200+
- upgrade 2005/06
- 4 times better sensitivity than
NT200 for PeV cascades
- basic cell for km3 scale detector
140 m
12 clusters of strings
NT1000: top view




Sacrifice low energies (muon threshold ~ 10 TeV)
Protoype strings being tested
Modular clusters, stepwise installation > 2012
~ 2000 optical modules (conventional PMs)
L~ 350
m
Gigaton Volume Detector, GVD
All other deep water/ice detector projects started
around 1990 or later.
In the eighties /early nineties, shallow detectors
have been proposed but never built.
On the other hand, deep underground detectors
reached their full blossom:
- solar neutrinos
- supernova neutrinos
- limits on proton decay
- first hints to neutrino oscillations
- sky maps
Shallow detector projects
 Advantages: easy access, less challenging environment
 Disadvantages: huge background, not expandable
 GRANDE
– Shallow water, Lake, Arkansas, H. Sobel (Irvine)
 LENA
– Artificial water pool, Gran Sasso, M.Koshiba
 SINGAO
– Resistive Plate Chambers, Italy/UK
 Swedish lakes
– Early nineties, before Sweden joined Amanda
Underground Detectors
 KGF
 Baksan
 FREJUS
 Soudan
 IMB
 Kamiokande
Superkamiokande
 MACRO
e.g. MACRO, 1356 upgoing muons
~ 1000 m²
Neutrino oscillations, proton decay
 Deficit of solar neutrinos
(see Kai Zuber‘s talk)
 Deficit of atmospheric neutrinos
as function of distance and
energy
|m232| = (2.6±0.2) ·10-3 eV2
|m221| = (8.3±0.3) ·10-5 eV2
12 = 33.9º±1.6º
23 = 45º±3º
13 < 9º
 Stringent limits on proton life
time
1990-2000: revisiting the expectations
 Underground detectors, 1000 m², only for young
Supernovae in our Galaxy (Berezinsky)
 New estimates on neutrinos from Supernova remnants and
other galactic sources based on observations with Whipple
and HEGRA
 For supernova remnants, microquasars, extragalactic
sources: need detector of order 1 km³.
 The Waxman-Bahcall bound
 The Mannheim-Protheroe bound
 GRB as sources of cosmic rays and neutrinos
Diffuse Fluxes 2002
This model was downcorrected by a factor
of 20 in 2005.
 bound
MPR bound
WB bound
The ice option
F. Halzen
 1988: Pomerantz workshop,
NSF Science and Technology Center for the
South Pole (A. Westphal, T.Miller, D. Lowder,
B. Price)
 E. Zeller (Kansas) suggests to F. Halzen radiodetection of
neutrinos in Antarctic ice
 1989: attempt of Westphal and Lowder to measure ice
transparency in existing boreholes
 Jan. 89, ICRC, Adelaide: Decide to propose Amanda (B. Price,
D. Lowder, S. Barwick, B. Morse, F. Halzen, A. Watson)
 1990: Morse et al. deploy PMTs in Greenland ice
Nature
Sept 91
South Pole
 1991/91 first small PMTs deployed
 Results consistent with 25 m absorption length
Heaters and pumps
to melt the holes
93/94
40 m
1 km
Catastrophal delay
of light between
strings 20 m away!
(µsec instead of 100 nsec)
2 km
Explanation remnant
bubbles which are
disapppearing with
increasing depth.
Amanda B4
1995: DESY and Stockholm build
~ 100 modules, 86 deployed in
the season 95/96 at 1450-1950 m depth
The DESY crew
B4: first 2 neutrinos 
Drilling
Hot water drilling
AMANDA B10
IceCube
will work !
1 km
96/97 AMANDA - B10
2 km
120 m
NATURE 2001
Skyplot of the
very first 17
Nu candidates
in B10
B10 skyplot
published
in Nature 2001
97/98
 3 long strings
 study deep and shallow
ice for future IceCube
0.02
1 km
Scattering
coefficient
(1/m)
vs. depth
2 km
120 m
0.1
0.5
AMANDA-II
1 km
99/00
2 km
200 m
Ocean Water
AMANDA results

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δ=90º
Max Significance
δ=54º, α=11.4h
Diffuse fluxes
3.38σ
Point sources
Neutrinos from GRB
WIMP searches
Magnetic Monopoles
0h
24h
Cosmic
rays
SN monitoring
Skymap from 7years AMANDA: no significant excess
….
No significant excess found
The one intriguing coincidence ….
WHIPPLE
Arrival time of
neutrinos from the
direction of the AGN
ES1959+650
Flux of
TeV photons
(arb. units)
3


2
1
0
May
2000
2001
2002
2003
Year
June
July
IceCube Observatory
07/08: 18
06/07: 13
05/06: 8
04/05: 1
08/09: 19 strings
Remaining:
22 IceCube Strings
5 DeepCore Strings
 complete in January 2011
Shadow of the Moon


Absolute pointing  1°
Angular resolution  1°
Downward muons, max. 28° above horizon, median energy of primary parent ~ 30 TeV
Cosmic Rays
0.5°
8 months IceCube 40 strings
90
Large-scale
anisotropy
of downgoing
muons
0
24h
12 TeV
IceCube
-90
90
(40 strings 2008)
anisotropies on the
per-mille scale
24h
0
126 TeV
(skymap in equatorial
coordinates)
-90
Compare to
Northern
hemisphere

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


Tibet air shower array
Compton-Getting
effect ?
Heliosphere effect ?
Nearby pulsar ?
Interstellar magnetic
field ?
First observation on
Southern hemisphere adds important
piece of information.
Simulation
(Lallement et al.
Science 2005)
MILAGRO
First look above horizon
(IceCube 2007, 22 strings)
PeV-EeV range
Northern hemisphere
Southern hemisphere
Point Sources: The Progress
factor
1000
in 15 years !
Diffuse Fluxes: The Progress
Baikal/
Another
factor
1000 !
Mediterannean projects
NESTOR
(since 1991)
„Amanda-sized“ -- under construction (?)
ANTARES (since 1996)
„Amanda sized“ -- data taking
NEMO:
R&D for km3 project
Since 2003: km3 initiative
KM3NeT
2400m
ANTARES
NEMO
3400m
4100m
NESTOR
NESTOR

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
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1991:
first site studies
1992:
first muon count
1992-2001:
many ocean tests,
build lab and
infrastructure
2000:
cable to site
2003:
deploy first floor.
Cable failure after
a few weeks
Compare to 2000
declared plan:
– deploy full
tower 2003
– deploy 6 more
towers 2005
ANTARES
Installation:
Junction Box - Dec 2002
Line 1
- March 2006
Line 5-1
- Dec 2007
Line 11-12 - May 2008
Antares results
NEMO
R&D for KM3NeT
- 4-floor tower in 2006
- full tower end of 2009
KM3NeT
Recommendations KM3NeT
 2001/02: High Energy Neutrino Astrophysics Panel
–
–
–
–
–
High physics interest
Need km³ scale
Need both hemispheres
No more than 1 Northern detector
Timely formation of Northern hemisphere deep water detector is encouraged
 2008: ApPEC
– The priority project for high energy neutrino astronomy is KM3NeT.
– Encouraged by the significant technical progress of recent years, the support
for working towards KM3NeT is confirmed.
– Resources for a Mediterranean detector should be pooled into a single
optimised design for a large research infrastructure, with installation starting in
2012.
– The sensitivity of KM3NeT must substantially exceed that of all existing
neutrino detectors including IceCube.
KM3NeT





Site
Size
Configuration
Technology
Deployment
2 km
Construction
Data taking
Design decision
…a long march
which has not
yet reached
its end.