Neutrino Astronomy with AMANDA

Steven W. BarwickUniversity of California-Irvine

SPIE Conference-Hawaii, 2002

Outline of Talk

•Science of HE Neutrino TelescopesPoint SourcesDiffuse Sources (up and down)GRBsWIMP annihilations in earth and sun

• Future developments in detector technology

Messengers of Astronomy

• The neutrino window begins at energies above 1013 eV

• Era of multi-messenger astronomy

Detection Method for

• Cherenkov photons are detected by array of PMTs

• Tracks are reconstructed by maximum likelihood method of photon arrival times.

1

2 3

4

5 6

South Pole

AMANDA-II

Dome

Skiway

The AMANDA-II Collaboration

• Bartol Research Institute, University of Delaware• BUGH Wuppertal, Germany• Universite Libre de Bruxelles, Brussels, Belgium• DESY-Zeuthen, Zeuthen, Germany• Dept. of Technology, Kalmar University, Kalmar, Sweden• Lawrence Berkeley National Laboratory, Berkeley, USA• Dept. of Physics, UC Berkeley, USA • Dept. of Physics and Astronomy, UC-Irvine, USA• Institute of Physics, University of Mainz, Mainz, Germany• University of Mons-Hainaut, Mons, Belgium• Fysikum, Stockholm University, Stockholm, Sweden• Dept. of Physics, University of Alabama, USA• Vrije Universiteit Brussel, Brussel, Belgium• Dept. Fisica, Univ. Simon Bolivar, Caracas, Venezuela• Dept. of Physics and Astronomy, Penn State University, College Station, USA• Dept. of Astronomy, Dept. of Physics, University of Wisconsin, Madison, USA• Physics Department, University of Wisconsin, River Falls, USA• Division of High Energy Physics, Uppsala University, Uppsala, Sweden• Dept. of Physics, Imperial College, London, UK

Institutions: 8 US, 10 European, 1 South American

AMANDA-II

depth

The AMANDA Detector

Super-K

• Early photons are red, late photons are blue. More photons are larger circles

• Bottom of array is toward center of earth

• Event is clearly traveling in the upward direction

AMANDA -event

Building AMANDA

Drilling Holes with Hot Water

The Optical Module

Optical Properties of Ice

Sensitivity to cascades and EHE physicsdemonstrated with in-situ sources

In-situ light sourceSimulated light source

Scatteringcoefficient(1/m)vs. depth

Detailed measurement of optical properties strong light scattering dust layers low absorption (in particular in UV !!)

TriggerLevel

After BGrejection

up horizon

A-II

B-10

dramatically increased acceptancetowards horizon

Nearly horizontal event

(experiment)

AMANDA-II

Arb

. uni

ts

Physics Reach of AMANDA-II

0

50

100

150

200

-1 -0.8 -0.6 -0.4 -0.2 0

Aeff

[ x10

3 m2]

Cos(theta)

E = 10 TeV

- Am II Trigger

- Am II Point Cuts

- 10 Am B Point Cuts

- Am II GRB Cuts

10-10

10-8

10-6

10-4

102 103 104 105 106

E2

(dN/dE ) [GeVcm

-2s

-1]

E( )GeV

- (3 )AMANDA II yr

- 10 ( 97)AMANDA B '

IceCube3 273C

Crab

AGN Core

501 (Mk =γ)

. Atm

Mk-501

Search for from TeV γ 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 /γ > 1

Sensitivity to point flux E2 F ~ 5 10-8 GeV cm-2 s-1 sr-1

Area depends on physics

0

0.1

1

10

-90 -60 -30 0 30 60 90

Φ

(cm-2sec-1

) 10x

14

( )Declination degrees

AMANDA-B10

Super Kamiokande MACRO

AMANDA-II (expected sensitivity)

Mk-501 /γ ~ 1

Point Source Limits

northern sky

southern sky

Submitted to ApJ: astro-ph/0208006

1 km

2 km

SPASE air shower array

calibration of AMANDA angular resolution and pointing !

confirms predicted angular resolution Amanda-B10 ~ 3° (due to tails, best fit by two component gaussian)

absolute pointing < 1.5°

Unique:

Analysis Checks

MC of Backgrounds Systematic Uncertainty

Atmospheric Neutrinos, 97 data

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

~ 300 events

cos()

Ahrens. et al. PRD(2002), astro-ph/0205109

• Improved coverage near horizon

• In 6o6o bin, for E-2 spectrum, and 10-8 cm-2 s-1 flux:

~ 2 signal

~1.5 background

0.40.61ES 1959+650

1.43.5SS433

0.50.7Cass. A

0.61.2Crab

0.50.75Markarian 501

0.50.75Markarian 421

(10-8 cm-2 s-1)muon (10-15 cm-2 s-1)Source\Sensitivity

Point Sources AMANDA-II

Event times scrambled for blind analysis purposes.

Equatorial coordinates: declination vs. right ascension.

~1129 events

Projected sensitivities calculated using background

levels predicted from 3 years of Am-II data on tape.

From 2000

Diffuse flux: Am-B10 limit

E2 Φ < 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

solid: experiment

dotted: atmos.

1st draft, to be subm. to Astr.Part.Phys.

10 km

AMANDA-II

High EnergyNeutrino

Micro-Black Hole

EHE (E 1016 eV) Search

• Main background: muon “bundles”

– Comparable NPMT but smaller Nγ

• Calibrate with in-situ N2 laser

• Still evaluating systematic uncertainties

EHE events very bright; many PMTs detect multiple photons

At EHE energies, expectonly events near horizon

R 10 km

Preliminary Limit

vert

ical

Diffuse upDiffuse down

3 months B10

AMANDA-II expected

Diffuse fluxes: theoretical bounds and experimental limits

atmo

sph

eric Neu

trino

s

W&B W&B

MPRMPR

DUMAND test string

FREJUS

NT-200+

AMANDA-II

IceCube (~2012)

NT-200

AMANDA-B10

MACRO

down

Big Question:Where do prompt muons from

CHARM come in?

GRB Analysis

• Search strategies1. Short duration (T90 < 1 s), composite2. All duration, composite3. All duration, maximize on single burst sensitivity

x

x

energy

x

x

x

up/down time

xPoint Sources: AGN,WIMPs

Diffuse ,

EHE events

Atmospheric

xx xxGRBs

source direction

GRB Analysis (‘97) - 88 BATSE bursts

1 hour 1 hour16 s

BKG - off time BKG - off timeon time

T90 of GRB burstBackground cuts can beloosened considerably high signal efficiency

Composite

AMANDA-II GRB Analysis (‘00) AMANDA-II GRB Analysis (‘00)

Check stability and maximize sensitivity for desired BG rejection

58 bursts (triggered and non-triggered)Feb-May 2000

Stability

RA-DEC

AMANDA-II GRB Analysis (‘00) AMANDA-II GRB Analysis (‘00)

Compute probability to get observed events froim random fluctuation

10-2

10-1

100

0 0.5 1 1.5 2

Occurance Fraction

-log(P)

Random Fluctuation of BG No evidence for

neutrino emission by any GRB

GRBs

Occ

urre

nce

Fra

ctio

n

AMANDA-II GRB Analysis (‘00) AMANDA-II GRB Analysis (‘00)

The effective area of AMANDA-II is enormous, nearly 0.06km2

For W-B flux, the most probable

detected energy is ~105 GeV

Aef

f(km

2 )

Log(EGeV)

WIMP annihilation in sunWIMP annihilation in sun

Freese, ’86; Krauss, Srednicki & Wilczek, ’86Gaisser, Steigman & Tilav, ’86

Silk, Olive and Srednicki, ’85Gaisser, Steigman & Tilav, ’86

Sun

Earth

Detector

velocitydistribution

scatt

capture

annihilation

interactions

int. int.

Limits on WIMP annihilation in Earth

WIMP annihilationat Earth’s center

MSSM/DarkSUSY

AMANDA

Earth

astro-ph/0202370, to appear in PRD

(Area approximate)

soft

hard

• Disfavored by recent direct

searches

2002 real time analysis

event June 6

Daily transmission ~ 1 GB via satelliteFull data to tape (available next polar summer)

Monitoring shifts in home labs

From 02/03:Iridium connection for supernova alarm

MPR[1.5]

W&B

20% Amanda II cascade limit (Y2K)

nγ<1

nγ>>1

0.50Prompt charm

(RQPM)

0.15e (CC), e+ (NC)

Predicted events in 100% of 2000 data

Atmospheric ’s

3.2Φ+

= 10-6 E-2 GeV

cm-2 s-1

5.5Φe+e

= 10-6 E-2 GeV

cm-2 s-1

Predicted events in 100% of 2000 data

Astrophysical ’s

Cascade limits

AMANDA begins to challenge model predictions, Prel. diffuse limit is below “weak” theoretical boundDiscovery potential

Preliminary results from AMANDA-II GRB, Atmospheric NeutrinosPoint sources: soon

Trans-GZK events revived interest in EeV physicsExcellent sensitivity to EeV neutrinos

Promising future:Real-time data analysisNew DAQ with full waveform readout>2 more years of AMANDA-II data on tapeThere is a great deal more to do!

Summary and Outlook