IceCubeIceCube

S Robbins

University of Wuppertal

Moriond - “Contents and Structures of the Universe”

La Thuile, Italy, March 2006

Outlook for NeutrinoDetection at the South Pole

Outlook for NeutrinoDetection at the South Pole

• Scientific Goals

• IceCube Status

• AMANDA Results

Amundsen-Scott South-Pole Station

USA (14)USA (14)Europe (15)Europe (15)

JapanJapan

New ZealandNew Zealand

• Alabama University, USA• Bartol Research Institute, Delaware, USA• Pennsylvania State University, USA• UC Berkeley, USA• UC Irvine, USA• Clark-Atlanta University, USA• University of Alaska, Anchorage, USA• Univ. of Maryland, USA

• Alabama University, USA• Bartol Research Institute, Delaware, USA• Pennsylvania State University, USA• UC Berkeley, USA• UC Irvine, USA• Clark-Atlanta University, USA• University of Alaska, Anchorage, USA• Univ. of Maryland, USA

• IAS, Princeton, USA• University of Wisconsin-Madison, USA• University of Wisconsin-River Falls, USA• LBNL, Berkeley, USA• University of Kansas, USA• Southern University and A&M College, Baton Rouge, USA

• IAS, Princeton, USA• University of Wisconsin-Madison, USA• University of Wisconsin-River Falls, USA• LBNL, Berkeley, USA• University of Kansas, USA• Southern University and A&M College, Baton Rouge, USA

• Universite Libre de Bruxelles, Belgium• Vrije Universiteit Brussel, Belgium• Université de Mons-Hainaut, Belgium• Universiteit Gent, Belgium• Humboldt Universität, Germany• Universität Mainz, Germany• DESY Zeuthen, Germany• Universität Dortmund, Germany

• Universite Libre de Bruxelles, Belgium• Vrije Universiteit Brussel, Belgium• Université de Mons-Hainaut, Belgium• Universiteit Gent, Belgium• Humboldt Universität, Germany• Universität Mainz, Germany• DESY Zeuthen, Germany• Universität Dortmund, Germany

• Universität Wuppertal, Germany• MPI Heidelberg, Germany • Uppsala University, Sweden• Stockholm University, Sweden• Imperial College, London, UK• Oxford University, UK• Utrecht University, Netherlands

• Universität Wuppertal, Germany• MPI Heidelberg, Germany • Uppsala University, Sweden• Stockholm University, Sweden• Imperial College, London, UK• Oxford University, UK• Utrecht University, Netherlands

• University of Canterbury, Christchurch, NZ• University of Canterbury, Christchurch, NZ

ANTARCTICA

The IceCube Collaboration

• Chiba University, Japan• Chiba University, Japan

Physics GoalsDetect neutrinos from the sources of cosmic-rays

Search for neutrinosfrom dark matterannihilations

Search for neutrinos from cosmological events

NewPhysics

Fermi acceleration of protons gives particle spectrum

dNp/dE~ E-2

Neutrino production at source: p+ or p+p collisions gives pions

± -> ± +

± -> e± + + e

Neutrino flavors:

e : : 1:2:0 generic sources1:1:1 after oscillations

Observing Neutrinos

IceCube

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IceTop air shower array80 pairs of ice Cherenkov tanks

IceCube (deep ice)80 strings of 60 optical modules17 m between optical modules125 m between strings1 km3 (1 Gton) detector!

AMANDA19 strings, 677 OMs totalø 200m, height 500m

~1

0-20

m

Optical module

Mean - angle is ~0.7o at 1TeV

Muon travels a large distance Interaction can be outside the detector Active volume is much larger than the detector

Proposed by Markov 1960

νμμ

X X’

W

detection principle

energy deposited in OM

time recorded on OM

Optical module

νe,τ

N X

W

e,τ

νμ,e,τ

N X

Z

νμ,e,τ

Charged-current interactions:

Neutral-current interactions:

e & detection principle

energy deposited in OM

time recorded on OM

Ice Properties• Ice not uniform in depth (e.g. dust layers)• Important to understand ice for analysis

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Mean scattering length: 25m Mean absorption length: 110m

Light Propagation• Cherenkov cone from muon tracks• Use timing information, accounting for propagation

Homogeneous ice Depth Dependent ice properties

Hot-water drilling

Hose reel Drill tower

IceTop tanks5 MW Hot water generator

AMANDA

IceCube Today

500 m

Only IceToptank

InIce string& IceTop

• 2004/2005 season– New hot water drill – First string deployed (string 21)– Four IceTop stations installed

(16 OMs)– 60 OMs in deep ice,

all 60 functioning

• 2005/2006 season– Modified drill – 8 strings deployed– 12 IceTop stations installed– 480 OMs in deep ice

and 48 OMs in IceTop

“String 21” DataFirst IceCube string, deployed January 2005

Neutrino candidate9 string

Downgoing

IceCube event

AMANDA

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IceTop air shower array80 pair of ice Cherenkov tanks

IceCube (deep ice)80 strings of 60 optical modules17 m between optical modules125 m between strings1 km3 (1 Gton) detector!

AMANDA19 strings, 677 OMs totalø 200m, height 500m

“Diffuse Limits”• Measure the neutrino energy spectrum• Search for a break in the spectrum

Some AGN models excluded at 90% CL :Szabo-Protehoe 92

Stecker, Salamon. Space Sc. Rev. 75, 1996

Protehoe. ASP Conf series, 121, 1997E2μ

(E) < 2.6·10–7 GeV cm-2 sr-1 s-1

Results from one year (2000) of data

Consistent with Atmospheric neutrino expectation

Point Source SearchNeutrino sky map:

• 2000-2003 data: 807 days livetime• 3329 neutrino events• Largest significance = 3.4 (92% chance occurrence)• No significant excess observed

• 2000-2003 data: 807 days livetime• 3329 neutrino events• Largest significance = 3.4 (92% chance occurrence)• No significant excess observed

Neutrinos from GRBs

10 min -1 hour+1 hour

1.4501.29312 (BT)B-10/A-II97-00

1.8800.6046 (New)A-II2000

1.4701.24114 (All)A-II2000

2000

2000

1999

1998

1997

Year

A-II

A-II(2 analyses)

B-10

B-10

B-10

Detector

2.1900.2424 (BNT)

1.72/2.050/00.83/0.4044 (BT)

2.2400.2096 (BT)

2.2400.2094 (BT)

2.4100.0678 (BT)

Event U.L.NObsNBG, PredNBursts

Using space and time coincidence leads to a very low background.

No observed signal

Only ~1 order of magnitude above Waxmann&Bahcall prediction

Solar WIMPs

• Neutralinos captured in the Sun• These annihilate producing quarks and leptons• And neutrinos, which we search for with IceCube

χ + χ → ν + ν (+…)

Earth

Detector

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

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

Neutralinos from the Sun

data from 2001

Sun

Limits on muon flux from Sun

IceCube Best-Case

Conclusions• 2005/6 was a successful deployment season• Now have in total 604 optical modules installed• Only ~1% failure rate• IceCube is on track for 1km3 neutrino observatory• AMANDA has taken 10 years of data• AMANDA continues to produce physics results

• No extraterrestrial neutrinos observed so far

• Stay tuned…