IAU Sydney 2003-07-18

Per Olof Hulth

Particle Astronomy from

Antarctica

Per Olof Hulth

Stockholm University

IAU Sydney 2003-07-18

Per Olof Hulth

Why Particle Astronomy from Antarctica?

• Difficult logistics

• No continues access during the year

• Cold and expensive

• Long time to build up large experiment

IAU Sydney 2003-07-18

Per Olof Hulth

Antarctic platform

• 24 hours coverage of astronomical objects

• Largest ice sheet with very transparent ice

• Unique wind conditions at high altitudes

• Low magnetic field cut off for cosmic charged particles

• Possibility to combine large surface detectors with neutrino telescopes in the ice

• South Pole special with the sources at constant zenith angles

IAU Sydney 2003-07-18

Per Olof Hulth

One large common question to answer for Particle Astronomy from Antarctica

From where are the cosmic rays coming?

Medium energy Supernovas?

Super High energy

GRB? AGN? ??

LHC

Galactic?

Extra galactic?

IAU Sydney 2003-07-18

Per Olof Hulth

What are the sources of the Cosmic rays?

Galactic?Extra galactic?

Some new physics?

?Galactic?

Extra galactic?

IAU Sydney 2003-07-18

Per Olof Hulth

Cosmic ray investigations

• Determine the chemical composition and energy dependence of CR – Detect the incoming CR before interacting in the atmosphere

(Balloon flights and space flights)

– Only one particle at 1015 eV/m2 and year! Direct detection possible up to 1015 eV. Above 1015 eV using large air shower detectors at

surface. But identification of primary particle depending on simulations of the shower development.

• Detect CR sources by neutrino production at the source.

IAU Sydney 2003-07-18

Per Olof Hulth

Dark matter detection by neutrinos

Sun

Earth

Detector

IAU Sydney 2003-07-18

Per Olof Hulth

Different projects in Antarctica

• Balloon Cosmic ray detectors– CREAM– Tiger – ATIC– TRACER– Polar Patrol Balloon

(PPB)

• Surface Cosmic ray detectors – SPASE– IceTop

• Neutrino Cherenkov telescopes – AMANDA– IceCube

• Neutrino radio telescopes– Rice– Anita

IAU Sydney 2003-07-18

Per Olof Hulth

Balloons

• NASA is using McMurdo as a base for launching Balloons for altitudes up to 37km

• Long duration flights (LDF) up to three weeks• Ultra Long duration flights (ULDF) up to 100

days.

• Only 5-10 grams/cm2 of the atmosphere remains.

IAU Sydney 2003-07-18

Per Olof Hulth

Balloon Cosmic ray detectors

• ATIC 1010 - 1014 eV H - Fe

• CREAM 1012 - 5 1015 eV H - Fe

• TIGER 108 - 1010 eV Fe - Zr

• TRACER - 1014 eV O - Fe

• Polar Patrol Balloon (PPB) 1010 - 1012 eV electrons

IAU Sydney 2003-07-18

Per Olof Hulth

CREAM

CREAM

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Per Olof Hulth

19 days of scientific mission Dec 02 - Jan.03

ATIC

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Per Olof Hulth

IAU Sydney 2003-07-18

Per Olof Hulth

Tiger

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Per Olof Hulth

Polar Patrol Ballon (PPB)

Detector launched from Syowa station

See poster 2013 IAU00287 by Toii Shoji

IAU Sydney 2003-07-18

Per Olof Hulth

Messengers of Astronomy

Only neutrinos cover the whole energy range

IAU Sydney 2003-07-18

Per Olof Hulth

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

Neutrino fluxes from Cosmic ray sources

IAU Sydney 2003-07-18

Per Olof Hulth

Estimation of diffuse neutrino flux

Atm

osp

heric n

eutrin

os

W&B W&B

MPRMPR

Demands km3 size detectors!!

IAU Sydney 2003-07-18

Per Olof Hulth

Neutrino telescopes

• Needs large volumes of optical transparent material => ice sheet!

IAU Sydney 2003-07-18

Per Olof Hulth

~ 5 m

Detection of e , ,

Electromagnetic and hadronic cascadesO(km) long muon tracks

direction determination by cherenkov light timing

15 m

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Per Olof Hulth

Measured Ice properties at South Pole

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Per Olof Hulth

AMANDA

The worlds largest running neutrino telescope situated at the South Pole

Year DetectorTotal

number ofOM

1995/1996 AMANDA-B4 86

1996/1997 AMANDA-B10 302

1998/1999 AMANDA-B13 428

1999/2000 AMANDA-II 680

IAU Sydney 2003-07-18

Per Olof Hulth

South Pole

Dark sector

AMANDA

IceCube

Dome

Skiway

IAU Sydney 2003-07-18

Per Olof Hulth

QuickTime™ and aGIF decompressorare needed to see this picture.

AMANDA-II event 2000

• AMANDA observes about 3-4 atmospheric neutrinos/day in a atmospheric muon background 106 times larger.

IAU Sydney 2003-07-18

Per Olof Hulth

AMANDA - deployment

IAU Sydney 2003-07-18

Per Olof Hulth

Atmospheric muons in AMANDA-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

IAU Sydney 2003-07-18

Per Olof Hulth

Atmospheric 's in AMANDA-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 usedto study excess due to cosmic ‘s

IAU Sydney 2003-07-18

Per Olof Hulth

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

PRELIMINARY

Point source search in AMANDA II

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

sky subdivided into 300 bins (~7°x7°) no clustering observed

above horizon:mostly fake events

IAU Sydney 2003-07-18

Per Olof Hulth

IceCube

1400 m

2400 m

AMANDA

South Pole

IceTop

Skiway• 80 Strings• 4800 PMT • Instrumented volume:

1 km3 (1 Gt)• IceCube is designed to

detect neutrinos of all flavors at energies from 107 eV (SN) to 1020 eV

IAU Sydney 2003-07-18

Per Olof Hulth

Status of IceCube

• 15 $M approved for Fy02 • 25 $M for FY03• 295 $M in presidents budget for FY04 (should

cover the full detector plus 4 years of running)• New hot water drill to be sent to South Pole 03/04• Up to 6 IceCube strings to be deployed 04/05 (and

then up to 16 strings per year)

IAU Sydney 2003-07-18

Per Olof Hulth

IceCube:Top View

AMANDA

SPASE-2South Pole

Dome

Skiway

100 m

Grid North

Counting House

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Per Olof Hulth

Finished DOM Ready to Pack and Test

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Per Olof Hulth

Eµ=10 TeV Eµ=6 PeV

Simulated -events in IceCube

Measure muon energy at the detector by counting the number of fired PMTs.

IAU Sydney 2003-07-18

Per Olof Hulth

Mediterranean (ocean) Antares, Nestor, 1 km3 ...

South Pole (ice)AMANDA, ICECUBE

dots: distribution of gamma ray bursts (GRBs)

galactic center in middle

E < 100 TeV

Complementarity (point sources):

IAU Sydney 2003-07-18

Per Olof Hulth

SPASESPASE is an air shower detector at the South Pole for showers above

5 *1013 eV.

SPASE measure the electromagnetic component of the shower

AMANDA the muon component!

Unique combination!!

IAU Sydney 2003-07-18

Per Olof Hulth

AMANDA-SPASE

•Plot muons vs. electrons

•Transformed axes correspond to mass and energy

Protons

Iron

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Per Olof Hulth

IceTop - IceCube

• Particle astrophysics– using surface/under-ice coincidences as a novel

probe of primary cosmic-ray spectrum to 1018 eV

• Calibration – with tagged muons

• Veto – of certain backgrounds for signals

IAU Sydney 2003-07-18

Per Olof Hulth

EeV Detection in IceCube with shower veto

This background for EeV events can be vetoed by detecting the fringe of the coincident horizontal air shower in an array of water Cherenkov detectors (cf. Ave et al., PRL 85 (2000) 2244, analysis of Haverah Park)

Penetrating muon bundle in shower core

Incident cosmic-ray nucleus

Threshold ~ 1017 eV to veto this background

IAU Sydney 2003-07-18

Per Olof Hulth

Radio detectors

Very high energy cascades emits Cherenkov radiation in radio wave length

Larger attenuation length than optical -> larger volumes

But higher energy threshold (> 10 PeV)

IAU Sydney 2003-07-18

Per Olof Hulth

Antennas deployed down to a few hundred meters in the AMANDA holes.

Testing since 1996

Preparing an application for a

larger RICE together with IceCube

RICE South Pole

IAU Sydney 2003-07-18

Per Olof Hulth

Flight in 2006

ANITA

(Antarctic Impulsive Transient Array)

IAU Sydney 2003-07-18

Per Olof Hulth

Summary

• Antarctica as a very successful platform for particle astronomy!