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