High energy neutrino astrophysics: latest results and future prospects

Transcription

High energy neutrino astrophysics: latest results and future prospects
High‐Energy Neutrino Astrophysics
Latest results and future prospects C. Spiering, Moscow, August 22, 2013
DETECTION PRINCIPLE
Detection Modes
ƒ Muon track from CC muon ƒ Cascade from CC electron/tau neutrino interactions
and NC all flavor interactions
ƒAngular resolution < 1°
ƒAngular resolution 10° at 100 TeV
ƒdE/dx resolution factor 2‐3
ƒEnergy resolution ~ 15% Detection Modes
ƒ Muon track from CC muon ƒ Cascade from CC electron and neutrino interactions
NC all flavor interactions
ƒAngular resolution < 1°
ƒAngular resolution 10° at 100 TeV
ƒdE/dx resolution factor 2‐3
ƒEnergy resolution ~ 15% PRESENT DEVICES
Baikal – Antares ‐ IceCube
Baikal
Antares
AMANDA
IceCube
3600 m
1366 m
Lake Baikal
NT200
NT200+
NT200
1366 m
3600 m
ANTARES
V. Bertin - CPPM ARENA'08 @
Roma
2500m
70 m
885 PMTs
• 12 strings
• Operating in final
•
configuration
since 2008
450 m
IceCube Neutrino Observatory
IceTop air shower detector
81 pairs of water Cherenkov tanks
IceCube 1450m
2450m
2820m
86 strings including 8 Deep Core strings
60 PMT per string
DeepCore
8 closely spaced strings
ƒ ~220 ν/day
ƒ Threshold
‐ IceCube ~ 100 GeV
‐ DeepCore ~10 GeV
STUDY OF ATMOSPHERIC
NEUTRINOS
Baikal 1996
4-string stage (1996)
NT-96
Atmospheric neutrinos in IceCube
proton
c,(b)
prompt
e,
μ
π
νe,μ
μ
ν
e
μ
ν
ν
μ
conventional
e
Atmospheric neutrinos in IceCube ...
.. and ANTARES
arXiv:1308.1599
Oscillations of atmospheric neutrinos
Muon neutrino survival probability
Vertically upward
AN T
A RE
S/De
epCo
re
cosmic
ray
ν
Earth
L
θ
Horizontal
Oscillations of atmospheric neutrinos
Muon neutrino survival probability
AN T
A RE
S/De
epCo
re
Vertically upward
PL B714 (2012)
ANTARES
cosmic
ray
2σ
Earth
1σ
ANTARES
K2K
MINOS
SuperK
L
θ
Horizontal
ν
Oscillations of atmospheric neutrinos
Muon neutrino survival probability
Vertically upward
AN T
A RE
S/De
epCo
re
cosmic
ray
ν
Earth
L
θ
Horizontal
Oscillations of atmospheric neutrinos
Muon neutrino survival probability
AN T
A RE
S/De
epCo
re
Vertically upward
Standard
oscillations Horizontal
Oscillations
to sterile ν
Non‐standard
oscillations due
to VLI
L
SEARCH FOR
EXTRA-TERRESTRIAL NEUTRINOS
• Steady point sources
• Transient sources: GRB
• Diffuse flux
Point Source IceCube 4 years IC40/59/79/86
April 2011-March 2012
N o r t h
S o u t h
Point Source IceCube 4 years IC40/59/79/86
April 2011-March 2012
N o r t h
S o u t h
ANTARES 5 years 2008‐2013
ƒ 5516 upward going events (90% purity)
ƒ excess at α=‐46.8° δ=‐64.9°
ƒ p‐value 2.1% Æ 2.3σ
Limits for steady point sources
ƒ Factor 1000 in 12 years
ƒ No detections yet
early Amanda limit
ƒ ANTARES is best at Southern Sky IceCube sensitivity at Southern sky only for cut‐off at >> PeV
IceCube 4 years
preliminary
ƒ Expect another factor 3 for IceCube in 2016
Southern Sky | Northern Sky
ƒ KM3NeT/GVD would give ~ factor 50 w.r.t. Antares
Transient Sources
ƒ GRB (second to minute scale) ƒ AGN (Flares on hours to week scale)
ƒ Binary systems (periodic behaviour)
ƒ ANTARES and IceCube: Various follow‐up programs (ν → γ, ν → optical) and common searches for coincidences LIGO/VIRGO ANTARES/IceCube ƒ IceCube: SN burst trigger
GRB Coincidence Search: IceCube
ƒ 225 GRB at Northern sky (IC40 + IC59)
ƒ No IceCube event in time and direction coincidence
ƒ 8.4 coincidences expected (Guetta et. al)
Standard fireball model à la Waxman
or Guetta excluded with > 3σ
(Nature 484 (2012) 351)
Winter et al. have modeled the
fireball numerically, using more
realistical particle energy
distributions, and got fluences
less by nearly one order of
magnitude !
GRB Coincidence Search: ... and ANTARES
ƒ 296 GRB at Southern sky
ƒ No ANTARES event in time 007
2
RES
A
T
AN
3
201
S
RE
A
T
AN
012
2
be
u
C
Ice
and direction coincidence
ƒ arXiv:1307.0304
„
dashed grey
2007, 40 GRB
(JCAP 03 (2013) 06
„
Dotted blue/red: Antares 2013
„
dashed black
IceCube 225 GRB
„
Blue: Guetta et al. 2004
Red: Hümmer et al, 2010
„
ANTARES
GRB Coincidence Search: ... and ANTARES
A
A
E
R
A
NT
S
E
R
NT A
7
0
0
S 2
3
1
0
2
2
1
0
2
e
b
u
C
e
Ic
Diffuse extraterrestrial neutrino fluxes
ƒ ANTARES, Amanda, IceCube: Upwards going muons
ƒ Amanda, IceCube: contained cascades
ƒ Baikal, IceCube: Extremely high energies, all‐sky
ƒ IceCube: galactic plane
ƒ ANTARES: Fermi bubbles
Search for an extraterrestrial diffuse ν
flux
Atmospheric Neutrinos
proton
c,(b)
prompt
e,
μ
π
νe,μ
μ
ν
e
μ
ν
ν
μ
conventional
e
Search for an extraterrestrial diffuse ν flux
proton
c,(b)
prompt
e,
μ
π
νe,μ
μ
ν
e
μ
ν
ν
μ
conventional
e
IceCube‐59: upward muons
ƒ A 200 TeV muon crossing IceCube
ƒ The higest energy muon we have detected
ƒ 1.8σ excess
ƒ IC‐79 data coming soon !
Limits on diff. fluxes from upward muons
ANTARES 2008‐2011
E² Φ < 4.7 × 10‐8 GeV cm‐2 s‐1 sr‐1
ƒ
ƒ
ƒ
ƒ
Baikal NT‐200
AMANDA
ANTARES
IceCube 40, IceCube 59
IceCube contained cascades
ƒ IceCube‐40
~ 220 TeV
ƒ 3 cascade events 2.3 σ excess
~ 140 TeV
ƒ IceCube‐59
ƒ Mild excess over conventional atm. neutrinos
~ 140 TeV
Special Search for cosmogenic ν
ƒ IC79/IC86
2.8 σ
(Berezinsky Zatsepin)
Ernie
Bert
~1.2 PeV
~ 1.1 PeV
ƒ Both downgoing
ƒ Not from Glashow Resconance (which is at 6.3 PeV)
ƒ Unbroken E‐2 would have made 8‐9 events at higher energy Æ cut‐off
Follow‐up Analysis: HESE submitted to SCIENCE
ƒ HHigh Energy Starting Event Analysis
ƒ
ƒ
ƒ
ƒ
Muon Veto
Qtot > 6000 photoelectrons
400 Mton eff. Volume
Sensitive to all flavors above 60 TeV
100 TeV 1 PeV
HESE Results: Ernie & Bert + 26 additional events
ƒ Significance of all 28 events: 4.1 σ
ƒ Background 10.6+5.0‐3.6
Results are consistent with previous analyses ƒ Best fit for E‐2 spectrum:
E2Φ = 4.8 × 10‐8 GeV cm2 s‐1 sr‐1
ƒ Cut‐off at 1.5‐2 PeV
Ernie and Bert
HESE Skyplot: Nothing significant !!!
Looking Ahead
ƒ One very high‐energy event in the 10% „burn sample“ of 2012 data: BigBird
ƒ Expect 2012 HESE results in fall 2013
BigBird
ƒ Also: ƒ upgoing muon analysis IC79 (2010)
ƒ Cascade analysis IC79
ƒ Get the 5σ soon. But: do we understand systemactic well enough?
THE FUTURE
Water detectors KM3NeT,
Mediterranean Sea, several blocks à 1‐2 km³
(alltogether ~5 km³), sensitive above 1 TeV
GVD, Lake Baikal, 0.5 km³ ... Æ 1.5 km³ ?
sensitive above 3 TeV
KM3NeT
KM3NeT
Distributed infrastructure
‐ KM3NeT‐France (Toulon) ~2500m
‐ KM3NeT‐Italy (Capo Passero) ~3400m
‐ KM3NeT‐Greece (Pylos)
~4500m
Until 2015: construction of KM3NeT phase I detectors in France and Italy (~40 M€)
A Gigaton Volume Detector at Lake Baikal ?
Gigaton Volume Detector (GVD) in Lake Baikal
NT200 + GVD prototype
1 km
GVD
Engineering array April 2013
A Gigaton Volume Detector at Lake Baikal ?
Gigaton Volume Detector (GVD) in Lake Baikal
NT200 + GVD prototype
1 km
GVD
See talk of Zh. A. Djilkibaev
Options for IceCube Extensions
IceCube
DeepCore
ƒ PINGU: low energy extension of DeepCore
12,6 km3
Threshold for muons ~ 50 TeV, gain eff. area for muons ~ factor 4, gain for cascades ~ factor 10
ƒ Aim: Measure ν Mass Hierarchy
ƒ Plan: deploy 2016/17 – 2019/20
ƒ see talk of J. Brunner
SUMMARY
ƒ Factor of 1000 improvement over last 12 years
ƒ No indications of point sources yet
ƒ Further factor 3 in sensitivity will bring us to the level of optimistic predictions for some SNR
ƒ KM3NeT and GVD look to central part of the Galaxy and could eventually find point sources!
ƒ Another option: IceCube++
ƒ IceCube constrains models for GRB
ƒ IceCube finds first strong indications for a diffuse flux of extraterrestrial high‐energy neutrinos
ƒ Light at the end of the tunnel or Fata Morgana?
ƒ The next months will give the answer!
BACKUPS
Effective Area
Effective area
log. eff. area (m²)
1
4
IceCube
3 2 1 1
0
‐1
‐2
‐3 2 3 4 5 6 7 8 9 log Eν (GeV)
Effective Area
2
Effective area
log. eff. area (m²)
4
IceCube
3 2
2 1 0
‐1
‐2
‐3 2 3 4 5 6 7 8 9 log Eν (GeV)
Effective Area
Effective area
log. eff. area (m²)
3
4
IceCube
3 2 1 0
‐1
‐2
3
‐3 2 3 4 5 6 7 8 9 log Eν (GeV)
Neutrinos from GRB
t ~ t90 Æ ?
t~
-10 Æ-100s
t ~ 0 Æ t90
HESE results: 26 more events
3 example events
upward
downward
Ernie&Bert
Declination vs. deposited energy
Atmospheric neutrinos: Charm component?
arXiv:1308.1599
Scales
Baikal NT200
IceCube
1 km³
0.0001 km³
ANTARES
0.01 km³
DeepCore
~0.01 km³
Signal and Background