First-generation neutrino telescopes. neutrino muon or tau Cerenkov light cone Detector interaction...

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first-generation first-generation neutrino telescopesneutrino telescopes

neutrino

muon or tau Cerenkov

light cone

Detector interaction

•Infrequently, a cosmic neutrino is captured in the ice, i.e. the neutrino interacts with an ice nucleus

•The muon radiates blue light in its wake

•In the crash a muon (or electron, or tau) is produced

•Optical sensors capture (and map) the light

size perspectivesize perspective

50 m

Amundsen-Scott Station South Pole

Optical module

1996-2000

AMANDA IIAMANDA II

South PoleSouth Pole

AMANDA– 1 mile deepAMANDA– 1 mile deep

Building Building AMANDAAMANDABuilding Building AMANDAAMANDADrilling Holes with Drilling Holes with

Hot WaterHot Water

The Optical ModuleThe Optical Module

Christchurch, New ZealandChristchurch, New ZealandInternational Antarctic CenterInternational Antarctic Center

Logistics simple!Logistics simple!

thethe domedome

the new stationthe new station

Building AMANDABuilding AMANDA

AMANDA IIAMANDA II

• up-going muonup-going muon• 61 modules hit61 modules hit

ttiimmee

size ~size ~ number of photonsnumber of photons

> 4 neutrinos/day> 4 neutrinos/day on-lineon-line

AMANDA AMANDA Event Event

Signatures:Signatures:MuonsMuons

AMANDA AMANDA Event Event

Signatures:Signatures:MuonsMuons

+ N + N + + XX

CC muon neutrinoCC muon neutrinoInteractionInteraction tracktrack

two eventstwo events

200 TeV e

event reconstructionevent reconstruction

• Maximum Likelihood Maximum Likelihood methodmethod

• Take into account time Take into account time profiles of expected profiles of expected photon flight timesphoton flight times

• Bayesian approach - Bayesian approach - use prior knowledge use prior knowledge of expected of expected backgrounds and backgrounds and signalssignals

Quality parameters: Quality parameters: Example 1: The track Example 1: The track

lengthlength• Short track

length = more likely to be background

Ldir m

Data

Atmospheric MC

0

5

10

15

20

25

30

05 0 100 150 200 250 300 350 400

Quality parameters: Quality parameters: Example 2: The Example 2: The

smoothnesssmoothness• The smoothness is a

measure of how regular the photon density is distributed along the track.

• A well reconstructed muon track is more likely to have a high smoothness.

| SPhit |

Data

Atmospheric MC

0

5

10

15

20

25

30

35

40

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

High Low

Quality parameters: Quality parameters: Example 3: The Example 3: The

angular difference angular difference between 2 fitsbetween 2 fits

• A well reconstructed event has better agreement between a simple fit and a full likelihood reconstruction.

like - LF

Data

Atmosph. MC

0

5

10

15

20

25

30

35

40

-60 -40 -20 02 04 06 08 0 100

Quality ParametersQuality ParametersQuality ParametersQuality Parameters• LikelihoodLikelihood• Zenith angle Zenith angle

mismatch between mismatch between two types of fits.two types of fits.

• Sphericity of Hits Sphericity of Hits (Brem?)(Brem?)

• Track Length (is an Track Length (is an energy cut, too)energy cut, too)

• Smoothness of hits Smoothness of hits along the trackalong the track

• Number of Number of unscattered photonsunscattered photons

• Combine 6 to a Combine 6 to a ssingle event ingle event quality quality parameter.parameter.

• Only 3 for Only 3 for completed completed detector!detector!

quality cutquality cut

Data

Atmospheric MC

Downgoing m MC

Quality Cut

10-1

1

10

10 2

10 3

10 4

0 2.5 5 7.5 10 12.5 15 17.5 20 22.5 25

Atmospheric muons and Atmospheric muons and neutrinosneutrinos

• Atm. Neutrinos (): 60/day• Atm. Muons: 8.6*106/day

Lifetime: 135 days

Observed Data

Pred. Neutrinos

Triggered1,200,000,00

04574

Reconstructed upgoing

5000 571

Pass Cuts (Q ≥ 7) 204 273

Atmospheric Neutrinos, 97 data

vertically up horizontally AMANDA sensitivity understood down to normalization factor of ~ 40% (modeling of ice ...)

~ 300 events

Understanding Ice and Understanding Ice and Calibrating AMANDACalibrating AMANDA• In situ light sourcesIn situ light sources

– Ice propertiesIce properties– Relative PMT timing, gainRelative PMT timing, gain– Response to electromagnetic showersResponse to electromagnetic showers– crosstalkcrosstalk

• Downgoing cosmic-ray muonsDowngoing cosmic-ray muons– Relative PMT timing, gainRelative PMT timing, gain

• AMANDA-SPASE coincidencesAMANDA-SPASE coincidences– DirectionalityDirectionality– Ice propertiesIce properties

• Atmospheric neutrinosAtmospheric neutrinos– Full detector responseFull detector response

Amanda: time delay due to Amanda: time delay due to scatteringscattering

Amanda: time delay due to Amanda: time delay due to scatteringscattering

3 50 200 400 700

6 m

17 m

d=32 m

delay, nsec

d

muon

Ice PropertiesIce PropertiesIce PropertiesIce Properties

• Most Most challenging challenging initial initial problems now problems now understood understood using using in situin situ lasers and lasers and LEDsLEDs– Disappearance Disappearance

of bubblesof bubbles– Mapping of Mapping of

dust layersdust layers

scatter scatter :: 6 m - 52 m6 m - 52 m

abs abs : 9 m - 240 m: 9 m - 240 m

AMANDA Is Working Well: 4 nus AMANDA Is Working Well: 4 nus per day!per day!

• Sensitivity to up-going muons demonstrated with CC atm. nm interactions:

• Sensitivity to cascades demonstrated with in-situ sources (see figs.) & down-going muon brems.

In-situ light source Simulated light source

• AMANDA also works well with AMANDA also works well with SPASE:SPASE: • Calibrate AMANDA angular responseCalibrate AMANDA angular response• Do cosmic ray composition studies.Do cosmic ray composition studies.

Horizontal Up-going

MCData

290 atm. candidates(2000 data)

Zenith

Detector capabilitiesDetector capabilities

muons:directional error: 2.0 - 2.5°energy resolution:¶ 0.3 – 0.4coverage: 2

primary cosmic rays: (+ SPASE)energy resolution:¶ 0.07 – 0.10

„cascades“: (e±, , neutral current)zenith error: 30 - 40° energy resolution:¶ 0.1 – 0.2coverage: 4

effective area (schematic):

E

3 cm2

-interaction in earth, cuts

2 -5m2

100 GeV 100 TeV 100 PeV ¶[log10(E/TeV)]

AMANDA-IIAMANDA-IIAntarctic Muon And Neutrino Detector Antarctic Muon And Neutrino Detector

ArrayArray•Construction began Construction began in 1995 (4 strings)in 1995 (4 strings)•AMANDA-II AMANDA-II completed in 2000 completed in 2000 (19 strings total)(19 strings total)•677 optical 677 optical modulesmodules•200 m across200 m across•~500 m tall (most ~500 m tall (most densely densely instrumented instrumented volume)volume)

The AMANDA detectorThe AMANDA detector

• Construction began in Construction began in 1995 (4 strings)1995 (4 strings)

• AMANDA-II completed in AMANDA-II completed in 2000 (19 strings total)2000 (19 strings total)

• 677 optical modules677 optical modules• 200 m across200 m across• ~500 m tall (most densely ~500 m tall (most densely

instrumented volume)instrumented volume)

Slant Depth

17

30

m

8650m

1 2 3 45

67

8

Slant Depth BinningSlant Depth Binning zenith angle cos zenith angle cos θθ

Required background Required background rejectionrejection

SignatureSignature Neutrino signal Neutrino signal //

cosmic muon cosmic muon bkgbkg

Diffuse fluxDiffuse flux ~10~10-8-8

Point sourcePoint source >>1010-6-6

Gamma ray Gamma ray burstburst

>>1010-4-4

Atmospheric muons in Atmospheric muons in AMANDA-IIAMANDA-II

PRELIMINARY threshold energy ~ 40 GeV (zenith averaged)

Atmospheric muons and neutrinos: AMANDA‘s test beams

much improved simulation...but data 30% higher than MC ...

normalize to most vertical bin

Systematic errors:

10% scattering ( 20m @ 400nm) absorption (110m @ 400nm) 20% optical module sensitivity 10% refreezing of ice in hole

Down-going Muon Down-going Muon FluxFlux

zenith zenith angleangle

depthdepth

Atmospheric Atmospheric ’s as Test Beam’s as Test Beam

Neutrino energy in Neutrino energy in GeVGeV

Atmospheric n's in Atmospheric n's in AMANDA-IIAMANDA-II

neural network energy reconstruction regularized unfolding

measured atmospheric neutrino spectrum

1 sigma energy error

spectrum up to 100 TeV compatible with Frejus data

presently no sensitivity to LSND/Nunokawa

prediction of dip structures between 0.4-3 TeV

In future, spectrum will be usedIn future, spectrum will be usedto study excess due to cosmic to study excess due to cosmic ‘s‘s

PRELIMINARY

Cosmic Ray flux measurement

empirical separation of ice and OM sensitivity effects

PRELIMINARY

In some cases ice and OM-sensitivity effect can be circumvented ...

(E)=0E-

Compatible and competitive () with direct measurements

for QGSJET generator:

(H) = 2.70 ± 0.02 0 (H) = 0.106(7) m-2s-1sr-1TeV-1

talk HE2.1-13

South Pole

Dark sector

AMANDA

IceCube

Dome

Skiway

South Pole Air Shower Experiment (SPASE)

AMANDA-II: 200 x 500 cylinder + 3 1km strings, running since 2000

cosmic ray composition studies SPASE-2 (electronic component) - AMANDA B10 (muonic component)

AMANDA II

- unique combination!

talk HE 1.1-25

robust evidence for composition change around knee ...

AM

AN

DA

(co

rrel

ate

to #

muo

ns)

SPASE-2 (correlated to #electrons)

iron

proton

log(E/G

eV)

publication in preparation

Composition change around „knee“

1998 data

1015 eV 1016 eV

talk HE 1.1-25

A=30

A=6

confirms trend seen byother experiments ...

blue band: detector and model uncertaintiesred band: uncertainty due to low

energy normalization

1 km

2 km

SPASE air shower arraySPASE air shower array

Cosmic ray composition

preliminary

RelativistiRelativistic c

Magnetic Magnetic MonopoleMonopole

ss10-16

10-15

10-14

10-18

10-17

= v/c= v/c

1.000.750.50

up

per

lim

it (

cmu

pp

er li

mit

(cm

-2-2 s s

-1-1 s

r s

r-1-1))

C - light output C - light output nn22·(g/e)·(g/e)22

n = 1.33n = 1.33

(g/e) = (g/e) = 137137/ / 22

8300

KGF

Soudan

MACRO

Orito

Baikal

Amanda

IceCube

electrons

Excess of cosmic neutrinos?

Electron + tau (2000 data)

„AGN“ with 10-5 E-2

GeV-1 cm-2 s-1 sr-1

.. for now use number of hit channels as energy variable ...

muon neutrinos (1997 B10-data)

cuts determined by MC – blind analyses !

Excess of cosmic neutrinos? Not yet...

cascades (2000 data)

„AGN“ with 10-5 E-2

GeV-1 cm-2 s-1 sr-1

.. for now use number of hit channels as energy variable ...

muon neutrinos (1997 B10-data)

cuts determined by MC – blind analyses !

2.5 ·106 – 5.6 ·108 GeV:

E2 (E) < 7.2 10-7

GeV-1 cm-2 s-1 sr-1

3·103 – 106 GeV:

E2 (E) < 8 10-7

GeV-1 cm-2 s-1 sr-1

Expected sensitivity 2000 data:~ 3 10-7 GeV-1 cm-2 s-1 sr-1

AMANDA II (with 3 years data):~ 10 X higher Sensitivity

Diffuse flux muon neutrinos

Note that limits depend on assumed energy spectrum ...

prel.

diffuse limit cascadesdiffuse limit cascades

Effective volume

80 TeV – 7 PeV For E2(E) =10-6 GeV cm-2s-1sr-1

flux would expect:

9.3 e , 6.2 , 8.0 events

2 candidate events total observed

E2all (E) < 9·10 - 7 GeV cm-2s-1sr-1

90% CL limit, assuming e:: =1:1:1 :

PRELIMINARY

flux results summary (all flux results summary (all flavors)flavors)

assuming e:: =1:1:1 ratio:

2000 analysis will yield comparable result ...

special analysis for resonant

production (6.3 PeV)

multiplicative factor 3 applied for single e , channels …

eWe ee

...can combine analyses!

theoretical bounds and future

atmospheric

W&B W&B

MPRMPR

DUMAND test string

FREJUS

NT-200

MACRO

NT-200+

AMANDA-II 5 years

IceCube

AMANDA-97

AMANDA-00 100 days

opaque for neutrons

Mannheim, Protheroe and Rachen (2000) – Waxman, Bahcall (1999) derived from known limits on extragalactic protons + -ray flux

neutrons can escape

Excess of cosmic neutrinos?

Electron + tau (2000 data)

„AGN“ with 10-5 E-2

GeV-1 cm-2 s-1 sr-1

.. for now use number of hit channels as energy variable ...

muon neutrinos (1997 B10-data)

cuts determined by MC – blind analyses !

Ultra High Energy Neutrinos in AMANDAUltra High Energy Neutrinos in AMANDA

• Energy > 10 PeVEnergy > 10 PeV

• All skyAll sky

• Large neutrino cross sectionsLarge neutrino cross sections

•Large muon range (> 10 km)Large muon range (> 10 km)

Competitive with radio, acoustic and Competitive with radio, acoustic and air shower experimentsair shower experiments

diffuse EHE neutrino diffuse EHE neutrino flux limitsflux limits

a) Stecker & Salamon (AGN)

b) Protheroe (AGN)c) Mannheim (AGN)d) Protheroe & Stanev

(TD)e) Engel, Seckel &

Stanev

Ranges are central 80%

AMANDAAMANDASensitivity (00-03)Sensitivity (00-03)

sky subdivided into 300 bins (~7°x7°)

below horizon:mostly fake events

above horizon: mostly atmospheric ‘s 697 events observed above horizon 3% non-neutrino background for > 5° cuts optimized in each declination band

PRELIMINARY

point source search in AMANDA

Search for excess events in sky bins for up-going tracks

talk HE 2.3-5

no clustering observed - no evidence for extraterrestrial neutrinos ...

Sources declination 1997 ¶ 2000

SS433 5.0o - 0.7

M87 12.4o 17.0 1.0

Crab 22.0o 4.2 2.4

Mkn 421 38.2o 11.2 3.5

Mkn 501 39.8o 9.5 1.8

Cyg. X-3 41.0o 4.9 3.5

Cas. A 58.8o 9.8 1.2

selected point source flux limits

sensitivity flat above horizon - 4 times better than B10 ¶!

declination averaged sensitivity:

lim 0.23•10-7 cm-2s-1 @90%

PRELIMINARY

¶ published Ap. J, 582 (2003)

upper limits @ 90% CL in units of 10-8cm-2s-1

-90 0-45 9045

10-15

10-14

mu o

n s/c

m2 s

1

10-17

10-16

published data

1 km3 detector, 3 years1 km1 km33

expected sourcesensitivity

MACRO 8 years

N

AMANDA137 days

declination (degrees)

S

AMANDA+16 (2007)

GX339-4Antares

(2007+)

preliminary 2000 dataSS-433

Mark. 501

Crab

GRB GRB search in AMANDA search in AMANDASearch for candiates correlated with GRBs - background established from data

317 BATSE triggers (1997—2000) effective -area 50000 m2

low background due to space- time coincidence

No excess observed! assuming WB spectrum 4 x 10-8GeV/s/cm2/sr

analysis continues with non-triggered BATSE and IPN3 data …

<20°

PRELIMINARY

talk OG 2.4-7

• 90% upper limits calculated

using background

levels predicted from data

• “neutrino =gamma” sensitivity

• 0.04 km0.04 km22 area area above 10 TeVabove 10 TeV

3.12.5Cygnus X-3

0.8SS 433

1.00.7Cas-A

2.12.1Crab

1.51.3Markarian 501

3.02.6Markarian 421

(10-8 GeVcm-2 s-1)muon (10-15 cm-2 s-1)Source\90% limit

Point Sources Amanda II (2000)

0.6

AMANDA II 2000AMANDA II 2000

Declination RA(hours)Declination RA(hours) 6464 21 21 40 2140 21 20 920 9

-rays from -rays from 00 decay? decay?

EE NN (E (E) = ) = E E NN (E (E))

1 < 1 < < < 88transparent transparent sourcesource00 = = ++ = = -

acceleratoracceleratorbeam dumpbeam dump(hidden source)(hidden source)

flux predictedflux predicted Observed Observed -ray flux-ray flux

20 km20 km-2-2 yr yr-1-1 Crab sn remnantCrab sn remnant

35 km35 km-2-2 in 97 in 97 Markarian 501Markarian 501(9 for p(9 for p))

~