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 ?