Neutrino Telescopes

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Neutrino Telescopes
An experimental overview
Juan José Hernández Rey IFIC Instituto de
Física Corpuscular Universitat de València ?
C.S.I.C.
Terrestrial and Cosmic Neutrinos, Leptogenesis
and Cosmology July 4?23, 2004, Benasque
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Against Common Wisdom

• Common Wisdom
• Neutrino Telescopes are not experiments they
  are a way of life!
• Enter RD phase as a graduate student
• Participate in the design of the detector as a
  PhD student
• During your first post-doc you help to write the
  TDR
• Start construction during your second post-doc
• Keep on building it during your third post-doc
  (Spanish physicist)
• Come back home (RC) during the first data taking
• Try to understand the data as tenure track
• Get permanent position (if you understand the
  data)
• Get promoted (if you beat the WB limit)
• Get full Professorship (if you find one single
  source)
• But most likely, retire during the construction
  phase of the
• mythical kilometre cube

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Detection of extra-terrestrial neutrinos
Detection of the products produced in CC and NC
interactions (muons, EM showers) (Disclaimer not
all the projects will be covered)
Optical Cherenkov radiation
Acoustic detection
Radio emission
Atmospheric showers
Earth based
In space
In space
Earth based
In Ice
In water
AMANDA B-10 AMANDA II IceCube
Baikal ANTARES NEMO NESTOR
ANITA FORTE
RICE GLUE SalSA CODALEMA
SAUND SADCO (Greece) ANTARES RD IceCube
RD AUTEC AGAM
Auger Hi-res Flys eye
EUSO OWL
Med KM3
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Summary

• Optical Cherenkov detectors (10 MeV?100 PeV)
• Amanda II has already provided very interesting
  limits
• IceCube starts 2005, fully deployed in 6 years
• ?2007 ANTARES
• KM3 in Mediterranean TDR for 2006 ? ready in 5
  years?
• Fluorescence in (0.1?100 EeV)
• AUGER
• EUSO ? 2008?, OWL ? 2010?
• Radio detection
• RICE, GLUE and FORTE do have results
• Aggressive schedule of ANITA ? 2006!
• Time scale of Salt domes is still uncertain
• Acoustic detection
• Difficult technique, but first limits released!

Neutrino Astronomy will be a lively field during
the near future
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END OF TALK
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HYPERLINKS
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Optical Cherenkov
Lattice of Photomultipliers Optical Modules
Muon track direction from arrival time of
light Muon energy from energy loss and range
Cherenkov light cone
muon
neutrino
Neutrino telescope
interaction
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Scientific reach
?
Energy
GeV?100 GeV
? MeV
GeV?TeV
TeV?PeV
PeV?EeV
gtEeV
Technique
Range of upgoing muons
Overall increase of PMTs signal
Upward-going muons
Upgoing muons, cascades
Downgoing events
Events close to horizontal
Source / Physics
Sun Galactic Centre/ Dark matter Neutralinos
Point-like astro-sources/ AGNs, GRB SNRs, ?QSOs
Atmosphere/ oscillations
AGNs, TD ?GKZ
Supernova search
?
Other Physics topics
Monopoles, very LBL ? mixing, supermassive DM,
SUSY Q-balls, whys (what-have-yous)
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The Antarctic Muon and Neutrino Detector Array
AMANDA-B10 (inner core of AMANDA-II) 10
strings 302 OMs Data years 1997-99
Adapted from K. Woschnagg Neutrino 2004
AMANDA-II 19 strings 677 OMs Trigger rate 80
Hz Data years 2000-


Scattering
Absorption
Average optical ice parameters labs 110 m _at_
400 nm lsca 20 m _at_ 400 nm
Optical Module
PMT noise 1 kHz
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Atmospheric neutrinos
AMANDA test beam(s) atmospheric ? (and µ)
Slide from K. Woschnagg, Neutrino 2004
?Neural Network energy reconstruction ?Regularize
d unfolding ? energy spectrum
First spectrum gt 1 TeV (up to 300 TeV) - matches
lower-energy Frejus data
Energy spectrum in detector
How much E-2 cosmic ? signal allowed
within uncertainty?
PRELIMINARY
Limit on diffuse E-2 ?µ flux (100-300 TeV)
determine statistics in last bin with MC ?
confidence belts (FC)
E2??µ(E) lt 2.6107 GeV cm-2 s-1 sr-1
Includes 33 systematic uncertainty
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Limit on a diffuse ET neutrino flux (cascades)
Slide from K. Woschnagg, Neutrino 2004
Sensitive to all three flavors
Assuming E-2 signal spectrum
E2?all ?(E) lt 8.6107 GeV cm-2 s-1 sr-1
(flavor mixing ?e???? 111)
50 TeV lt E? lt 5 PeV
Glashow resonance E2??e(E 6.3 PeV) lt 2106
GeV cm-2 s-1 sr-1
Some AGN core production models excluded at 90
C.L. (dashed in figure)
paper submitted to Astropart. Phys.
2000 AMANDA-II limits 10 better than same
searches with AMANDA-B10
1997 Phys. Rev. D67 (2003) 1999 included in
submitted AMANDA-II paper
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Limit for UHE neutrinos
PeV - EeV
Adapted from K. Woschnagg Neutrino 2004
PRELIMINARY
E? gt 1016 eV Earth opaque ? look up
and close to horizon Bright events (high
Nchannel) ? low atmospheric µ background
Long µ tracks (gt10 km) Low fraction of
1-p.e. hits
Amanda ?µ 3
1997 data (AMANDA-B10) 131 days livetime
assuming an E-2 flux (1 PeV lt En lt 3 EeV)
NO EXCESS OBSERVED
E2 ?all ?(E) lt 1.5?10-6 GeV cm-2 s-1 sr-1
( ?e???? 111)
Paper in preparation
AMANDA-II (2000) similar Aeff, gain in exposure
time
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Diffuse muon neutrino fluxes
Slide from K. Woschnagg, Neutrino 2004
Model predictions and AMANDA (E-2) limits
Excluded predictions
Integral limits (cover 90 of final energy
spectrum)
diffuse (B10)
UHE/3
cascades/3
diffuse (B10)
cascades
unfolded
UHE
Quasi- differential limit
unfolded
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Search for HE neutrino point sources
Scrambled in azimuthal direction!
Highest 3.6 Above 3s 2 Expect 2.33 (from
random distribution)
Slide from K. Woschnagg, Neutrino 2004
? No excess in significance beyond randomly
expected
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Detector design (1)

• 12 lines
• 25 storeys / line
• 3 PMTs / storey
• 900 PMTs

ANTARES
350 m
to be deployed by 2005-2007
100 m
Submarine links
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Sky View
ANTARES 43o North 2/3 of time Galactic Centre
AMANDA South Pole
0.5 p sr instantaneous common view 1.5 p sr
common view per day
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Angular resolution
n
for high energies sq lt 0.3o (Quality of
water!)
water transparency labs 60?8 m (470 nm)
labs 26?2 m (370 nm)
m
light scattering leff 300 m (470 nm)
leff 100 m (370 nm)
?
scat
?

eff
-
cos
?
1
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Diffuse Limits
diffuse (B10)
AMANDA II UHE/3
AMANDA II cascades/3
ANTARES
1 year
3 years
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IceCube

• 80 strings
• 4800 PMTs in Digital Optical Modules (DOMs)
• 160 IceTop tanks
• 1400 m to 2400m depth
• 1 km3 instrumented
• Will detect neutrinos of all flavours at
  energies from 107 eV (SN) to ?1020 eV

Ice Cube Ice Top strings tanks
4 8 Jan 2005 16 32 Jan 2006 32 64 Jan
2007 50 100 Jan 2008 68 136 Jan 2009
80 160 Jan 2010
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IceCube II
IceCube at the South Pole
Dark sector
Skiway
AMANDA
Dome
South Pole
IceCube Outline
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IceCube III
IceCube at the South Pole
Dark sector
Skiway
AMANDA
Dome
South Pole
IceCube Outline
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Diffuse Limits
diffuse (B10)
AMANDA II UHE/3
AMANDA II cascades/3
ANTARES
1 year 3 years
IceCube
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EUSO (Extreme Universe Space Observatory)

• Detects UHECR from fluorescence (N2) and
  Cherenkov (1 of energy)
• Will observe atmosphere from ?400km (200,000 km2,
  ? 2 1012 tons)
• Space-time correlation of detected photons allow
  energy (?E?30) and angular determination (???1)
  
• Horizontal showers below 10 km are a signal of
  neutrinos (2000 km3)

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OWLOrbiting Wide-angle Light-collectors

• As EUSO, but with two satellites that allow
  stereo reconstruction of shower axis.
• Air fluorescence technique. Image 300400nm
  photons in 0.1 pixels _at_ 10ns timing from low
  earth (600-1200 km) equatorial orbit
• Observes 3105 km2sr aperture
• Can detect neutrinos via horizontal air-showers

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EUSO Sensitivity
From S. Bottai, Neutrino 2004
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The Askaryan effect (Gurgen Askaryan, 1961
Zas, Halzen, Stanev 1991-1992)

• Net charge is built up in E.M. cascades
• Bremssstrahlungpair production.
• Compton scattering knocks electrons off atoms,
  atomic electrons and positrons annihilate ?
  20?30 excess of negative charge.
• Cherenkov radio and microwave emission
• If shower propagates in a dielectric medium.
• For wavelengths much larger than the shower
  dimensions (coherence).
• Properties
• For radio waves ( few 102 MHz, ? ? few meters)
  coherence is assured.
• Some media are transparent to radio pulses ?
  Large detection volumes
• Erad ? Q2bunch ? E2particle !
• Emitted at Cherenkov angle (?? 1/? (GHz) ) ?
  Directionality!

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Experimentally confirmed
Saltzberg et al 2001
A high energy photon beam (SLAC) hits on 3.5
tons of silica sand (the EM shower is created
by a neutral beam to avoid charges in the
target) Microwave horns (1.7-2.6 GHz and 4.4-5.6
GHz) point to the shower
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Askaryan effect
100 polarized
in the
expected plane
Reflection from side wall

• 100 linear polarization in the antenna-shower
  axis plane
• Peak pulse field strength proportional to N ? in
  shower. Pulse power quadratic with shower energy
  (expected from coherence). (Follow-up SLAC T460
  (2002) 8 orders of magnitude!)
• Spectral dependence (field vs ?) compatible with
  expectations

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So what?

• For high energies this process and TR become
  dominant in the proper medium
• In ice (see figure) attenuation is smaller in
  the PeV? EeV range . Larger volumes with less
  detectors

• Radio Ice Cherenkov Experiment (RICE)
• Antarctic Impulsive Transient Antenna (ANITA)
• Salt-dome Shower Array (SalSA)
• Goldstone Lunar Ultra-high energy neutrino
  Experiment (GLUE)
• Fast On-orbit Recording of Transient Events
  (FORTE)

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RICE

• Using AMANDA drilling
• 200x200x200 m3
• at 100-300 m depth
• Deployed 1996-1998
• 20 antennas into ice (dipoleamplifiers peak _at_
  300 MhZ)
• 3 surface horns
• 1 line antenna
• First limits set
• 2 ns time accuracy
• Angular resolution ?10 at 10 GeV (for
  events scattered within 1km of array)

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RICE
Reflections in layers
astro-ph/0306408
0 m
-90 m
Refraction measurement
Future RICE CUBE ?
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GLUEGoldstone Lunar Ultrahigh neutrino Experiment

• 0.3 antenna beam x ?10 m surface layer
• ? 100,000 km3 !
• At ?100 EeV Lint ?60 km, grazing events
• (regolith aggregate of rocks and sand, mainly
  silicates)
• Search 6 ? above noise in all channels
• No events in 120 hours.

JPL/NASA Deep Space Network Antennas Goldstone,
California
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Limits Glue
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FORTE Fast On-orbit Radio Transient Experiment

• Pegasus launch in 1997
• 800 km orbit
• Primary goal lightning atmospheric discharges
• 30-300 MHz range
• 4 M triggers recorded 9/97-12/99

N. Lethinen et al., astro-ph/0309656 P.Gorham,
talk Hawai 02/2004
TIPP
Survey Greenlands for RF signals 1 event
survives cuts ? Limits
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Limits Forte
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ANITA concept (Antarctic Impulsive Transient
Antenna)
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• 1.5 M km2 at every point
• Antennas view 2 ? sr with 60 overlap
• Pulse direction determined from intensity
• gradiant, timing interferometry and polarimetry

• RF interference is good and transparency is
  adequate
• Angular res. ? 2 (zenith) and ?E/E ? 1
• Aggressive schedule Anita-lite 2004,
• Full ANITA 2006

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ANITA lite
From S. Barwick,APS talk 04/2004
18 days at float altitude,1.25 revolutions Data
recovered in Feb 04
Background event too long a signal
Piggyback on TIGER Launch Dec 03 2 Receiver
Horns RF Survey of Antarctica
100 ns
signal event
Preliminary results no obvious signal detected
Calibration Ground antenna sends pulse to
Anita-lite
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RADIO LIMITS

ANITA 30 days
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Radio and microwaves in Salt domes
l
Observed mass/kton
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SALSA. Salt-dome Shower Array

• L? (lt 1GHz) gt 500 m
• Depth to gt 10 km
• Diameter 3 ? 8 km
• Veff ? 100?200 km3
• Backgrounds negligible
• gt 2 ? sr

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World rock salt resources
SALT DOMES, Gulf Region, United States Mexico,
MICHEL T. HALBOUTY, Gulf Publishing Company, Book
Division, Houston, London, Paris, Tokyo,
1979 Handbook of World Salt Resources, Stanley
J. Lefond, PLENUM PRESS, NEWYORK, 1969
M.Chiba
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Different salt types
From M. Chiba (Tokyo Metropolitan U.)
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Attenuation length
Dielectric resonator
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RADIO LIMITS

Salsa 1 year

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Activities in acoustics at different sites
Group Experiment Location Activities
Stanford SAUND Bahamas data taking, signal processing, calibration , simulation
INR1 AGAM MP10 Kamtschatka,Black Sea signal processing, calibration , simulation
INR2, Irkutsk Baikal Lake Baikal signal processing, noise studies
ITEP Baikal, Antares Lake Baikal, Mediterranean detector RD, accel. tests, in situ tests at Baikal, signal processing, noise studies
Marseille Antares Mediterranean detector and installation RD, calibration, noise studies, simulation,
Erlangen Antares Mediterranean detector RD, accel. tests, calibration, simulation
Rom, Catania NEMO Mediterranean installation RD, noise studies, simulation
Un. Kingdom Rona, Antares Scotland, Med. simulation, signal processing , calibration
U. Texas Salt Dome Hockley detector RD, attenuation studies, material studies
Berkeley, DESY, Uppsala IceCube South Pole detector RD, accel. tests, material studies, simulation
From R. Nahnhauer at Neutrino 2004
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Study of Acoustic Ultrahigh-energy Neutrino
Detection
SAUND I
AUTEC
Signal simulation E ? ? 1020 eV
Refraction important for signal tracing
SAUND7 km2
J. Vandenbroucke et al., astro-ph/0406105
From R. Nahnhauer at Neutrino 2004
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a
SAUND II
Data Analysis
only simulated events in fiducial volume
(1023eV,1024 eV,1025eV)
J. Vandenbroucke et al., astro-ph/0406105
Data taking65 106 eventsin 195 days
Background rejection
First flux limit from acoustic detector
From R. Nahnhauer at Neutrino 2004
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BACKUP, SPARES
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limits
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Limits on diffuse fluxes
Slide from K. Woschnagg, Neutrino 2004
RICE
Flys Eye
Macro
AGASA
Frejus
Baikal
Amanda-B
NT-214
AMANDA-II ANTARES
AUGER nt
IceCube km3 in sea
OWL, EUSO
Learned Mannheim Spiering
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Gorham 2002