The IceCube Neutrino Telescope

Kyler KuehnCenter for Cosmology and AstroParticle Physics

The Ohio State University

Novel Searches for Dark MatterCCAPP

November 17, 2008

The IceCube Collaboration

USA: Bartol Research Institute, DelawarePennsylvania State UniversityUC BerkeleyUC IrvineClark-Atlanta UniversityUniversity of AlabamaUniversity of MarylandUniversity of Wisconsin-MadisonUniversity of Wisconsin-River FallsLawrence Berkeley National LabUniversity of KansasGeorgia Institute of Technology Southern University and A&M

College, Baton RougeUniversity of Alaska, AnchorageThe Ohio State University

Sweden: Uppsala Universitet Stockholm Universitet

UK:Oxford University

Belgium: Université Libre de Bruxelles Vrije Universiteit Brussel Universiteit Gent Université de Mons-Hainaut

Germany: Universität Mainz DESY-Zeuthen Universität Dortmund Universität

Wuppertal Humboldt Universität MPI Heidelberg RWTH Aachen

New Zealand: University of

Canterbury

Netherlands: Utrecht University

Switzerland: EPFL

Japan: Chiba

University

>30 institutions, ~250 members http://icecube.wisc.edu

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Skiway

Amundsen-Scott Station

South Pole

AMANDA

Counting House

Drill Camp

IceCube

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IceCube

IceTop

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The Enhanced Hot Water Drill (EHWD)

Drill camp (5 MW hot water heater)

Hot water hoses (2)

Hose Reel

Drill head

Solar heatedFacilities

IceTop Tanks(w/ sun shield)

Drill speeds ~ 2 m/minute~40 hours to drill a hole~12 hours to deploy a stringDeploy: DOMs, pressure sensors, Std. Candle, dust logger, …

EHWD in Action

A New Astronomical Messenger

Neutrinos open a new window onto astrophysical processes in ways which no other particle can

diffuse, GRB AGN, TD

Cutoff determined by μG galactic B fieldCutoff determined by e+e- threshold for stellar IR photons

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Neutrino Detection

• Neutrino interacts with a nucleon and produces a lepton

• Lepton emits Cherenkov light as it travels through ice (in 41° cone)

• Light is detected by Digital Optical Module (DOM)

• 35 cm pressure vessel surrounding a 25 cm Photomultiplier

• 400 ns recording time• 3 channels gives a 14 bit dynamic range• 1 - 2% of DOMs fail during freeze-in• 15 year survival probability 96%

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Neutrino Event Identification

Muon from IC40 Data

Tracks Cascades

Track-Like IceCube AMANDA

Time Resolution (nsec)

2 5-7

Energy Resolution (log10E)

0.3 – 0.4 0.3 – 0.4

Field of View 2π 2π

Cascade-Like IceCube AMANDA

Time Resolution (nsec)

2 5-7

Energy Resolution (log10E)

0.18 0.18

Field of View 4π 4π

IceCube Angular Resolution < 1°

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A Wealth of Science

Point Sources

Diffuse Sources

CRs

GZK/UHE

DM: Solar WIMPs

Supernovae

AGNs, GRBs:cosmicaccelerators?

?

(see subsequent talks)

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In 2006 AMANDA was merged into IceCube.

AMANDA Datasets

Year Livetime

2000 197 d

2001 193 d

2002 204 d

2003 213 d

2004 194 d

2005 199 d

2006 187d

Total* 3.8 years

Most published physics results are from AMANDA

completed 2000 completed 1997

* Not including AMANDA B-10 (1997-1999)

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IceCube Datasets#Strings Year Run Length CR Rate rate

IC1 2005 164 days 5 Hz ~0.01/day

IC9 2006 137 days 80 Hz ~ 1.5/day

IC22 2007 319 days 550 Hz ~ 20/day

IC40 2008 ~ 1year 1400 Hz

IC80 2011 10 years 1650 Hz ~ 200/day

IC1IC9IC22IC40

+++

• IceCube can measure the “background” cosmic ray μ flux• Allows evaluation of detector simulation as well as

– Cosmic ray flux and composition around the knee– Prompt contribution to muon flux from charm production

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Cosmic Ray Flux Measurement

Atm.

Atm.

Astrophysical Cosmic Ray

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IC9 Diffuse Analysis

• Preliminary sensitivity: E-2 dN/dE < 1.4 x 10-7 GeV/cm2/s/sr

• Roughly comparable to limit from AMANDA combined 4-year limit

Most stringent AMANDA limits:≤ 106 GeV - E-2 dN/dE < 9 x 10-8 [Ap.J 675, 1014, (2008)]> 106 GeV - E-2 dN/dE < 7.4 x 10-8 [Phys. Rev. D 76, 042008 (2007)]

E-3.7 E-2

• Search for excess of unresolved neutrinos from astrophysical sources

• Use energy based variables (NCh) to separate astrophysical from atmospheric

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Point Source Search

• Search for excess of astrophysical neutrinos from a common direction over the background of atmospheric neutrinos from the Northern hemisphere

Atm.

Atm.

Detector(Years)

Energy(TeV)

Live Time(days)

AMANDA B-10(1997-1999)

1 - 1000 623

AMANDA-II(2000-2004)

1.6 - 2600 1001

AMANDA-II(2000-2006)

1.6 -2600 1387

IceCube 22(2007)

5 - 5000 270

IceCube 22 + AMANDA

0.1 - 10 1657*

* Livetime varies for specific scenarios

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• 26 a priori source locations

• 60% of random datasets had a sigma higher than 3.35 - no excess seen

IceCube Point Source Searches

C. Finley et al. arXiv:0711.0353 [astro-ph] p.107-110

•  Unbinned likelihood + energy information•  Hottest spot at r.a.153º, dec.11º •  p‐value (pre-trials): 7×10‐7 (4.8σ)•  p‐value (post-trials) 1.34% (2.2σ) •  Consistent with background fluctuation

IC22

IC9

A Distant GRB

CGRO

IceCube

AMANDA

γ, ν

ν

IPN Satellites(Fermi, Swift, HETE, ...)

GRB timing/localization informationfrom correlations among satellites

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Cascade(Trig & Roll)

Cascade(Rolling)

search

WB

03W

B03

MN

06M

N06

R03bR03b

R03aR03a

R03b: Supranova modelWB03: Waxman-Bahcall modelR03a: Choked Burst modelMN06: Murase Nagataki model

GRBs in AMANDA & IceCube

• AMANDA search

• Over 400 GRBs in Northern Hemisphere

– Cascade search• Triggered search for 73

GRBs in both hemispheres• Rolling search for 2001-

2003

• IceCube– 93 SWIFT bursts during IC22– GRB080319B: brightest

(optical) burst ever• ~0.1 events predicted in

IC22 using fireball model• ~1 event predicted for

equivalent burst in IC80

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Future Plans• Deep Core (see subsequent talks)

– Greatly enhances IceCube sensitivity to lower energy ’s

• Lower mass solar WIMPs

• Atmospheric neutrinos

– Six new strings• 60 high QE DOMs in clear ice

• First string deployed 08/09,

• Remaining strings deployed 09/10

• Multi-messenger astronomy– Correlations with ROTSE, AGILE,

MAGIC, and LIGO

• New Technologies– 3 Prototype digital radio strings

deployed with IceCube strings– 4 Hydrophones deployed above

IceCube

Veryclearice

Dust concentration

D. Cowen, Neutrino 2008

Optional Slides

IceT

op C

ount

ing

Rat

e (H

z)

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Solar Physics

• IceTop is sensitive to ~GeV particles emitted by the Sun during outburst

• Monitor IceTop tanks rates– Can extract energy spectrum in

1 - 10 GeV region

• Paper in preparation

Dec. 13, 2006 Solar outburst seen by international monitoring network

Real Moon Dummy Moons

Obs. Exp. (°) (°)

(°)

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CR Moon Shadow• Select well reconstructed tracks and

look in angular bins

• See a 4 deficit in the direction of the moon in 3 mos. of IC40 data

• Independent method of calibrating IceCube’s angular resolution

Flux Limits for Point Sources