High Energy Neutrino Astronomy
description
Transcript of High Energy Neutrino Astronomy
High Energy Neutrino Astronomy
Christian SpieringDESY Zeuthen
TAUP 2001
Predictions and Bounds
log(E2 Flux)
log(E/GeV)TeV PeV EeV
3 6 9
pp core AGN p blazar jetTop-Bottom model
GRB (W&B)
Various recentmodels for transient sources
Classes of Models
Bounds to diffuse fluxes: WB
Waxman & Bahcall, 1999
sources optically thin to primary cosmic rays
fix the spectral index to 2
normalize to cosmic rays at 1019 -1020 eV
atmospheric flux
bound without evolution
bound with evolution *
* moderately dependent on cosmology
Bounds to diffuse fluxes: MPR
Mannheim, Protheroe,Rachen, 2000
do not assume a specific CR spectrum, use available upper limit on extragalactic proton contribution
allow also for optically thick sources (no neutrons escape)
atmospheric flux
W & B
MPR
optically thick for neutrons
optically thin
MPR limit for optically thin sources
109
1012
Emax=106
3 1013
3 1010
3 107
source spectra of neutronsQn(En) En
-1 exp(-En / Emax) cosmic ray spectrum after propagation through Universe
neutrino spectrum after propagation through Universe
red: limit without GZK shiftblue: renormaliztion after GZK shift
More bounds ....
E-2 , one source type
E-1 exp (-E/Emax )optically thick optically thin
with evolution
without evolution
generic blazar
EGRET blazar BL Lac
Bound construction parallels that for optically thin sources.Energy dependent opacities. Averaging over luminosity functions and z-distributions of EGRET blazars and BL Lac objects.
1 pp core AGN (Nellen)2 p core AGN Stecker & Salomon)3 p „maximum model“ (Mannheim et al.)4 p blazar jets (Mannh)5 p AGN (Rachen & Biermann)6 pp AGN (Mannheim)7 GRB (Waxman & Bahcall)8 TD (Sigl)
Diffuse Fluxes: Predictions and Limits
Mannheim & Learned,2000
MacroBaikal
IceCube
Amanda
Hidden SourcesYoung SN shells, binary submerged in red giant, coooned MBH, ...
Pre-AGN (prior to formation of massive black hole) Berezinsky & Dokuchaev, 2000
Collision & destruction o normal starsin a contracting central cluster Massive gas
envelope
NS & BH survive, furthercontraction and collisions
Repeating fireballs,particle acceleration inrarified cavity
Interactions in envelopeHE neutrinos
Muon events per source with E > 1 TeV, in 1 km2 detector:
N ~ 70
(assuming Lp = 1048 erg s-1 and distance = 103 Mpc)
Duration of pre-AGN hidden source phase ~ 10 years
Average number of galaxies just in hidden source phase: ~ 10-100
Hidden sources (2)
Alvarez-Muniz, Halzen, Hooper, 2000
z = 1 z distribution expect up to = 300 thousands of events/yrkm2
Also multiple events from -faint-bursts !
GRB“Reference” model: Waxman & Bahcall, 1997 emission from protons accelerated at internal & external shocks in fireball, ~ 300 normalization to CR
E2 dN/dE ~ 310-9 cm-2 s-1 sr-1 GeV between 100 TeV and 10 PeV
100 300 1000
-faint,high flux
Low flux,high energy
GRBMeszaros & Waxman, 2001Core collapse of massive stars relativistic fireball jet may either penetrate stellar envelope or may be choked
N ~ 0.2 (E /1053 erg) km-2 for z =1 (E 5 TeV)
103 events correlated with -bursts + more from -dark bursts
Paolis et al., 2001Shock-accelerated protons from GRB interact with external protons in dense cloud
neutrinos with few GeV to ~ 1 PeV single GRB at z=1 yields 0.1-1 event per km2 (E > 1 TeV)
GRB (quasi-thermal) from 0 decay
neutrinos
Cannon Balls
SN shell
242
2
1010)0(
zEkmd
dn inCB
‘s extremely forward collimated - the stronger the higher their energy
Cannon Ball Model of GRB
(Dar, De Rujula, Plaga)
Neutrinos from MicroquasarsWaxman, Loeb, 2001
Accreting stellar-mass BH or neutron star ejecting jets Radio outbursts with L ~ 1043 erg of order 1-10 Shock acceleration in electron proton plasma
Neutrino burst of several hours, preceding radio outburst
1-100 TeV neutrinos from proton–X-ray interactions
N (1km2) ~ 10-2 -1 3 (for distance 10 kpc) 8 for source along line of sight
several neutrino events per outburst
Experiments under ground
MACRO
Limit on flux from point sources Limit on diffuse flux
Limit on neutrino emission from GRB
Since 1989:1356 upward going
MACRO point source searchMACRO sky-map in equatorial coordinates
90% c.l. upper limits for 42 selected sources (red dots)
Selection of HE neutrinos:1. timing cut (upward)2. energy deposition in scintillators Rate of survived
events in 5.8 yr
ATMMC 1.1±0.5stat
AGNMC 0.54±0.03stat
DATA 2
E2 < 4.5 10-6 cm -2 s -1 sr –1
GeV
MACRO: limit on diffuse E-2 flux
MACRO: Neutrinos from GRB
Search for space-time correlationWith 2527 BATSE GRB between1991 and 1999
Flux < 0.8 x 10-9 cm-2
per average burst
about 10 times above optimisticpredictions (Paolis et al., Halzen & Hooper), about 100 times above Waxman & Bahcall)
1761 upward going muons(through-going and stopping)from 1264 live days (April 96-May 00)
1200 m2 acceptance area
Superkamiokande
Super-K: point source search
Upward muons undergroundSuper-Kamiokande 2.0 k eventsMACRO 1.4 k eventsBaksan 1.0 k events
IMB + K-II + KGF + Soudan + ... ~ 1.5 k events (?)
~ 6000 events sets scale for underwater/ice experiments
Experiments under water
3600 m
1366 m
Lake Baikal, NT-200: The Site
pair of 37 cm Quasar PMTs
NT-200: the detector
„Gold plated“ neutrino event, 4-string stage (1996)
NT-200: zenith angledistribution 234 days in 1998/99
19 hits
Lake Baikal: atmospheric neutrinos
Request upward moving light front (like from e.m. shower below detector) Then cut on # hits
Vertex distribution for E-2 e
Blue dots: time cutRed squares: # hit > 45
E2 < 1.9 10-6 cm-2 s-1 sr-1 GeV
Upper limit on diffuse flux of HE e
Reach upper limit in E2 3.5 10-7 cm-2 s-1 sr-1 GeV !
0.1 1 10 100 1000 PeV
NT-214
The Mediterranean Projects
Antares
Nestor Nemo test site
NESTOR
First Mediterranean project (founded 1991) Site: Pylos (Greece), 3800m depth
towers of 12 titanium floors each supporting 12 PMTs
Nestor Tower
Deployment plans
Schedule:2001:re-lay cable to siteand deploy 2 floors2003:full tower
ANTARES
-2400m
40 km
Submarine cable
Demonstrator Site 42°59 N, 5°17 E Depth 1200 m
ANTARES Site42°50 N, 6°10 E Depth 2400 m
Demonstrator Line: 8 OMs Nov 1999 - June 2000
Existing cableMarseille-Corsica
New Cable (2001)La Seyne-ANTARES
Marseille
ToulonLa Seyne sur Mer
0.05 km2 Detector: 900 OMs , Deploy 2002- 2004
Site, History, Schedule
The Detector
2500m2500m
300m300mactiveactive
Electro-opticElectro-opticsubmarine cablesubmarine cable ~40km~40km
Junction boxJunction box
Readout cablesReadout cables
Shore stationShore station
anchoranchor
floatfloat
Electronics containersElectronics containers
~60m~60mCompass,Compass,tilt metertilt meter
hydrophonehydrophone
Optical moduleOptical module
Acoustic beaconAcoustic beacon
~100m
10 strings12 m between storeys
ANTARES Performance
Very good angular accuracybelow 3 TeV angular error is dominatedby kinematics, above 3 TeV by recon-struction error (~ 0.4°)
Effective area: ~ 10 000 m2 at 1 TeV ~ 50 000 m2 at 100 TeV
E/E ~ 3 (1-10 TeV) 2 (> 10 TeV)
ANTARESNorthern Hemisphere
AMANDASouthern Hemisphere
Galactic Centre seen 80% of time
Galactic Centre not visible
Fraction of time sky visible
View of Sky: Complementary to AMANDA
NEMO
Nemo-2
Nemo3
Experiments under ice
AMANDA
Location:Geographic South Pole
Amanda –II:677 PMTs at 19 strings
AMANDA: Atmospheric neutrinos
~ 300 neutrinos from 130 days in 1997 (Amanda-B10)
Systematic still error ~ 50% (prediction atm. ~ 30%, experiment ~ 40% (ice properties, OM sensitivity)
AMANDA: limit on diffuse flux
E2 F < 0.9 10-6 GeV-1 cm-2 s-1 sr-1
„AGN“ with 10-5 E-2 GeV-1 cm-2 s-1 sr-1
Full: Experiment
Dots: Atmos.
Search for excess of high energy neutrinos
Optimize analysis for HE neutrinos
Use number of hit PMT as energy estimator.
Place cut according to Feldman-Cousins (using only MC)
Search for point sources
Optimize analysis on HE neutrinos and good angular resolution
Accept large background contribution
Systematic uncertainties
Other limits from AMANDA and BAIKAL
AMANDA, 78 BATSE bursts in 1997
WIMPs from center of Earth
RelativisticMagnetic MonopolesBaikal
AMANDA-II
TriggerLevel
After BGrejection
up horizon
A-II
B-10
dramatically increased acceptancetowards horizon
Nearly horizontal event
(experiment)
Physics Reach of AMANDA-II
0
50
100
150
200
-1 -0.8 -0.6 -0.4 -0.2 0
Aef
f [ x
103 m
2 ]
Cos(theta)
E = 10 TeV
Am-II Trigger
Am-II Point Cuts
Am-B10 Point Cuts
Am-II GRB Cuts
10-10
10-8
10-6
10-4
102 103 104 105 106
E2 (d
N/d
E )
[
GeV
cm-2s-1
]
E(GeV)
AMANDA-II (3 yr)
AMANDA-B10 ('97)
IceCube3C273
Crab
AGN Core
Mk501 (=)
Atm.
Mk-501
Search for from TeV sources
Milagrito all-sky search sets limit at > 1 TeV: 7-30 10-7 m-2 s-1, ( E-2.5)
Amanda probes similar flux if/ > 1
Sensitivity to diffuse flux E2 F ~ 5 10-8 GeV cm-2 s-1 sr-1
AMANDA-II and EeV searchTransmission of Earth for Neutrinos as a function of zenith angle and energy
Earth opaque above a few PeV
PeV acceptance around horizon
EeV acceptance above horizon
Downward- background athigh energies is small.
AMANDA-II and EeV search
10-4
10-3
10-2
10-1
100
101
102
-1 -0.5 0 0.5 1cos()
AGN (Protheroe)GZK*100
• Look for bright tracks passing inside and outside array• Background rejection “straightforward”
–Total energy and “energy flow” variables–SPASE vetoes large DW at relevant ECR
• Calibration possible using in-situ N2 laser–Equivalent to 200 TeV cascade in energy
Improve sensitivity above 10-100 PeV to
E2 F ~ 2 10-8 GeV cm-2 s-1 sr-1
Sensitive to some trans-GZK models !
80 strings,each with 60 PMTs
AMANDA-II
SPASE
South Pole
IceCube
02468
1012141618
s3/4 s4/5 s5/6 s6/7 s7/8 s8/9
Number ofstrings
IceCube: Search for diffuse -fluxes “AGN” dN/dE = 10-7 ·E-2 cm-2 sec-1 GeV-1
2.300 events / year
Atm. neutrinos (after quality cuts): 130.000 events / year
Atmospheric
AGN
Sensitivity after 3 years:E2 dN/dE (in cm-2 sec-1 GeV)
2.7 · 10-9 (limit expectation) 8.0 · 10-9 (5 detectable flux) (assuming a model with low
prompt neutrinop flux and galactic neutrinos as „signal“)
IceCube: Point Source Search
0.25
0.5
0.75
1
1.25
1.5
1.75
2
2.25
2.5
0 -1 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0
muon energy 0.1 to 1.0 TeVmuon energy 1.0 to 10.0 TeVmuon energy 10.0 to 100.0 TeV
cos(zenith angle)
Angular resolution:Expect improvement at high energies from WLS &use of waveform information
Sensitivity of IceCube after 3 years of operation (average for zenith angles > 90º):
dN/dE ~ 3.5 · 10 -9 · E-2 cm-2 sec-1 GeV-1
Improve limit by a factor of 2 ?
Within predictionsof many recent models
(1-100 TeV)
Energy spectra
Diffuse search
Point source search
Colored: standard reconstruction and cuts against fake eventsBlack: ultimate Nhit cuts to get the lowest limit
IceCube:Neutrinos from Gamma Ray Bursts
Only 200 GRB needed to detect/rule out WB99 flux
• Test signal: 1000 GRB a la Waxman/Bahcall 1999 • Expected no. of events: 11 upgoing muon events• Expected background: 0.05 events
• Sensitivity (1000 bursts): 0.2 dN/dE (Waxman/Bahcall 99)
The high energy frontier
Acoustic Detection
10 m
hydrophones
Improve S/N : many hydrophones (close to each other as well as at several strings)
Maximum of emission at ~ MHz
Renewed efforts along acoustic method for GZK neutrino detection
AUTEC: US Navy array in Atlantic:existing sonar array for submarine detection
Russia: AGAM antennas near Kamchatka:existing sonar array for submarine detection Russia: MG-10M antennas: withdrawn sonar array for submarine detection Greece: SADCO Mediterannean, NESTOR site, 3 strings with hydrophones
Baikal: first signals from air showers?
Sea-based
Acoustical
Detector of
Cosmic Objects
RICERadio Ice Cherenkov Experiment (1)
20 receivers+ transmitters
Triggers: 4 RICE 1 RICE + Amanda A 1 RICE + SPASE
firn layer (to 120 m depth)
UHE NEUTRINO DIRECTION
300 METER DEPTH
RICERadio Ice Cherenkov Experiment (2)
90% C.L.Upper Limits
10 TeV 1 PeV 100 PeV Neutrino Energy
D.Besson, 2000(preliminary)
Flux
dN/d(lnE)~ 10-6 cm-2 sr-1 yr-1
Horizontal or upward air showers at EeV
el.-magn.cascade
from e
hardmuons
from CR
for E 1018 - 1020 eV:
mass = 1-20 Giga-tonssensitivity 3·10-7 GeV·cm-2·s-1·sr-
1
Horizontal showers in AUGER
500 km
60 °
Horizontal showers seen by EUSO / OWL
E > 1019 GeV
Area upto 106 km2
Mass upto 10Tera-tons
AGASA 2001: < 10-5 GeV·cm-2·s-1·sr-1
GLUE (1)
E2·dN/dE < 10-4 GeV·cm-2·s-1·sr-1
Lunar Radio Emissions from Inter-actions of and CR with > 1019 eV
1 nsec
moon
Earth
Gorham et al. (1999), 30 hr NASA Goldstone70 m antenna + DSS 34 m antenna
at 1020 eV
Goldstone LunarUltra-high energyneutrino Experiment
Effective target volume~ antenna beam (0.3°) 10 m layer
105 km3
GLUE (2)
method is going to challengetopological defect models !
Limited by live time. Only a small portionof antenna time devoted to one project
Outlook
Amanda and Baikal challenge model predictions, Amanda is below “soft” theoretical bound Soon: 10 - 20.000 m2 arrays in Mediterranean Amanda-II (Antares, Nestor): discovery potential IceCube and km3-underwater array will come to the limits of discovery potential for diffuse sources below EeV. Main focus: point sources, transient sources. Acoustic and radio in ice still (or again) alive Trans-GZK events revived interest in EeV physics
Promising limits from AGASA, GLUE. Further improvement by AUGER, EUSO, OWL, ..
“Signal” at TAUP-2003 ?