News from the South Pole: Recent Results from the IceCube and AMANDA Neutrino Telescopes

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News from the South Pole Recent Results from
the IceCube andAMANDA Neutrino Telescopes

• Alexander Kappes
• UW-Madison
• PANIC 08
• November 2008, Eilat (Israel)

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Outline

• High-energy cosmic neutrino sources
• The IceCube and AMANDA neutrino telescopes
• Physics topics (recent results)
• Moon shadow
• Steady point-like sources
• Gamma ray bursts
• Dark Matter (WIMPs) ? Talk by Catherine De
  Clercq
• Exotic physics ? Talk by John Kelley

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Cosmic sources of high-energy neutrinos
Supernova remnants(Cas A)
Cosmic ray accelerator
Gamma-ray bursts(GRB 080319B, Swift)

• Target
• photon field
• molecular cloud
• interstellar medium

p p(g) ? p X 9 m nm
9 e ne nm cosmic ray
neutrinos
?
p p(g) ? p0 X cosmic ray photons
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Principle of neutrino detection

• infrequently, a cosmic neutrino crashes into an
  atom in the ice and produces a nuclear reaction
• muon travels kilometers in the ice

muon
nuclearreaction

• blue (Cherenkov) light produced
• optical sensors capture (and map) the light

nm
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The IceCube and AMANDA neutrino telescopes
IceTop

• Air shower detector
• 160 ice-tanks in surface array
• Threshold 300 TeV

AMANDA (1995-2000) 19 Strings 677 Modules
InIce

• 80 Strings each with
• 60 Optical Modules
• 17 m between Modules
• 125 m between Strings

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Backgrounds Atmospheric muons neutrinos

• Significantly higher sensitivity for up-going n
• High-purity (atmospheric) up-going neutrino
  sample after cuts

Data-MC comparison
Cosmic neutrinos typicallyhave harder spectra
(E-2)
Up-going n-induced muons
Down-going atm. muons
Backgrounds - Downgoing µ - Atmospheric ?
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Pointing accuracy the Moon shadow in IceCube
40-strings
Preliminary

• Moon shadow observed in first 3 months of IC40
  data
• Validates pointing capabilities Angular
  resolution
• IceCube 22 lt 1.5
• IceCube 80 lt 1

true moon
mean fromfake moons
difference
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2000-2006 AMANDA point source search
Max Significance
d54o, a11.4h 3.38s

• Unbinned likelihood method using energy
  information
• Final 7 year AMANDA (3.8 yr livetime) analysis
• 95 of RA-randomized skymaps have maximum
  significance gt 3.38 s ? Not significant

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2000-2006 AMANDA point source search
Max Significance
d54o, a11.4h 3.38s

• Unbinned likelihood method using energy
  information
• Final 7 year AMANDA (3.8 yr livetime) analysis
• 95 of RA-randomized skymaps have maximum
  significance gt 3.38 s ? Not significant

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Search for point sources with IceCube 22-strings
preliminary

• Unbinned likelihood method using energy
  information
• Hottest spot found at r.a. 153º , dec. 11º
• pre-trial p-value 710-7 (4.8 sigma)
• Accounting for all trials, p-value for analysis
  is 1.34 (2.2 sigma).
• At this significance level, consistent with
  fluctuation of background.

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Current neutrino flux limits / sensitivities
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Analysis of naked eye GRB 080319B

• March 19, 061249 UTC (duration 70 s)
• Position RA 217.9º, Dec 36.3º
• Brightest (optical) GRB ever observed z 0.94
  (DA 1.6 Gpc, light travel time 7.5 Gyr)
• Expect 0.1 events in IceCube 9-strings(Fireball
  model, G 300)

Pi-of-the-Sky (optical)
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Analysis of naked eye GRB 080319B

• March 19, 061249 UTC (duration 70 s)
• Position RA 217.9º, Dec 36.3º
• Brightest (optical) GRB ever observed z 0.94
  (DA 1.6 Gpc, light travel time 7.5 Gyr)
• Expect 0.1 events in IceCube 9-strings(Fireball
  model, G 300)
• Unbinned likelihood methodyields 0 signal events
  
• Expect O(1) event in IceCube 80from similar
  burst!

Pi-of-the-Sky (optical)
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Gamma-ray bursts with IceCube 22-strings

• Currently analyzing data from41 bursts (Swift,
  AGILE others)
• Individual modeling of burstsaccording to GRB
  fireball model
• Expected events
• average Waxman-Bahcall 0.7
• individual GRB spectra 0.5
• OutlookIceCube 80 will be able to seeWB GRB
  flux within few years

Discovery potential for average WB bursts
30 chance
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Conclusions and Outlook

• IceCube halfway completed (40 strings),
  completion planned for 2011
• Verification of pointing accuracy via observation
  of Moon shadow
• Search for point-like sources over the whole sky
• Final AMANDA 7 year (3.8 years livetime) analysis
• IceCube 22-string analysis
• no significant access above background observed
• Search for neutrinos from gamma-ray bursts
• Individual analysis of naked eye GRB 080319B?
  no signal events found
• Analysis results for 41 bursts with IceCube
  22-strings coming soon
• With the nearing completion of the first
  km3-scale detector, IceCube,neutrino astronomy
  enters into a new era

Exciting times lie ahead !
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The IceCube collaboration
The IceCube collaboration

• Uppsala University
• Stockholm University

University of Oxford

• Universität Mainz
• Humboldt Univ., Berlin
• DESY, Zeuthen
• Universität Dortmund
• Universität Wuppertal
• MPI Heidelberg
• RWTH Aachen

University Utrecht

• Univ Alabama, Tuscaloosa
• Univ Alaska, Anchorage
• UC Berkeley
• UC Irvine
• Clark-Atlanta University
• U Delaware / Bartol Research Inst
• Georgia Tech
• University of Kansas
• Lawrence Berkeley National Lab
• University of Maryland
• The Ohio State University
• Pennsylvania State University
• University of Wisconsin-Madison
• University of Wisconsin-RiverFalls
• Southern University, Baton Rouge

Chiba University

• Universite Libre de Bruxelles
• Vrije Universiteit Brussel
• Université de Mons-Hainaut
• Universiteit Gent
• EPFL, Lausanne

Univ. of Canterbury, Christchurch
32 Institutions, 250 members
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• Backup

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Effective muon neutrino area
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Separation of atmospheric and cosmic neutrinos

• Atmospheric neutrinos irreducible
  background(60,000 per year in IceCube with 80
  strings)
• Cosmic neutrinos typically have harder spectra
  (E-2)(detected events peak at higher energies)

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A Priori Source List for IC22
Obj. Name ra(deg) dec(deg)
p-value (pre-trial) ------------- -------
------ -------- MGRO_J201937
(304.830 , 36.830) 0.251 MGRO_J190806
(287.270 , 6.280) -----
Cyg_OB2 (308.083 , 41.510) -----
SS_433 (287.957 , 4.983) 0.317
Cyg_X-1 (299.591 , 35.202) -----
LS_I_61_303 ( 40.132 , 61.229) -----
GRS_1915105 (288.798 , 10.946) -----
XTE_J1118480 (169.545 , 48.037) 0.082
GRO_J042232 ( 65.428 , 32.907) -----
Geminga ( 98.476 , 17.770) -----
Crab_Nebula ( 83.633 , 22.014) -----
Cas_A (350.850 , 58.815)
----- Mrk_421 (166.114 , 38.209)
----- Mrk_501 (253.468 , 39.760)
----- 1ES_1959650 (299.999 , 65.149)
0.071 1ES_2344514 (356.770 , 51.705)
----- H_1426428 (217.136 ,
42.672) ----- 1ES_0229200 ( 38.202
, 20.287) ----- BL_Lac
(330.680 , 42.278) 0.368 S5_071671
(110.473 , 71.343) 0.309
3C66A ( 35.665 , 43.035) 0.313
3C_454.3 (343.491 , 16.148) -----
4C_38.41 (248.815 , 38.135) -----
PKS_0528134 ( 82.735 , 13.532) -----
3C_273 (187.278 , 2.052) 0.369
M87 (187.706 , 12.391) -----
NGC_1275 ( 49.951 , 41.512) 0.213
Cyg_A (299.868 , 40.734)
----- (only excesses reported, otherwise given
as ---)
Lowest p-value (0.07) is for 1ES 1959650. Not
significant after trial factor of 28 sources in
list.
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All Flavor GRB Limits from AMANDA II

• Limits from triggered searches assume 700 bursts
  per year
• 420 GBs investigated
• AMANDA starts to excludeflux models!
• Cascade search in IceCubemuch more
  competitive(factor 70 in instrumented vol.)
  Eff. volume (cascades) grows faster than eff.
  area (muon)!

Cascade searches (trig roll)
only rolling
Muonsearches (only trig)