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News from the South Pole: Recent Results from the IceCube and AMANDA Neutrino Telescopes. Alexander Kappes UW-Madison PANIC ‘08 November 2008, Eilat (Israel). Outline. High-energy cosmic neutrino sources The IceCube and AMANDA neutrino telescopes Physics topics (recent results)
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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)
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 PANIC'08, Eilat
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 9m+nm9e+ ne+nm cosmic ray + neutrinos ? p + p(g) → p0 + X cosmic ray + photons PANIC'08, Eilat
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 PANIC'08, Eilat
2007-2008: 18 Strings 2450m 1450m Currently deployed: 40 Strings 80 IceTop tanks 3 more seasons planned 2006-2007:13 Strings 2005-2006: 8 Strings 2004-2005 : 1 String 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 PANIC'08, Eilat
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 ν PANIC'08, Eilat
Pointing accuracy: the Moon shadow in IceCube 40-strings • Moon shadow observed in first 3 months of IC40 data • Validates pointing capabilities: Angular resolution: • IceCube 22 < 1.5° • IceCube 80 < 1° Preliminary true moon mean fromfake moons difference PANIC'08, Eilat
Significance 2000-2006 AMANDA point source search • Unbinned likelihood method using energy information • Final 7 year AMANDA (3.8 yr livetime) analysis • 95% of RA-randomized skymaps have maximum significance > 3.38 σ→Not significant Max Significance δ=54o, α=11.4h 3.38σ PANIC'08, Eilat
Significance 2000-2006 AMANDA point source search • Unbinned likelihood method using energy information • Final 7 year AMANDA (3.8 yr livetime) analysis • 95% of RA-randomized skymaps have maximum significance > 3.38 σ→Not significant Max Significance δ=54o, α=11.4h 3.38σ 3yr max significance: 3.73σ 1.5σ 5yr max significance: 3.74σ 2.8σ PANIC'08, Eilat
Search for point sources with IceCube 22-strings • Unbinned likelihood method using energy information • Hottest spot found at r.a. 153º , dec. 11º • pre-trial p-value: 7×10-7 (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. preliminary PANIC'08, Eilat
Current neutrino flux limits / sensitivities AMANDA 3.8 years IceCube 22 IceCube 80 PANIC'08, Eilat
Analysis of “naked eye” GRB 080319B • March 19, 06:12:49 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) PANIC'08, Eilat
Analysis of “naked eye” GRB 080319B • March 19, 06:12:49 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) PANIC'08, Eilat
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 • Outlook:IceCube 80 will be able to seeWB GRB flux within few years preliminary Discovery potential for average WB bursts ~30% chance PANIC'08, Eilat
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 ! PANIC'08, Eilat
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 PANIC'08, Eilat
Backup PANIC'08, Eilat
Effective muon neutrino area PANIC'08, Eilat
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) PANIC'08, Eilat
A Priori Source List for IC22 Obj. Name ra(deg) dec(deg) p-value (pre-trial) ------------- ------- ------ -------- MGRO_J2019+37 (304.830 , 36.830) : 0.251 MGRO_J1908+06 (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_1915+105 (288.798 , 10.946) : ----- XTE_J1118+480 (169.545 , 48.037) : 0.082 GRO_J0422+32 ( 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_1959+650 (299.999 , 65.149) : 0.071 1ES_2344+514 (356.770 , 51.705) : ----- H_1426+428 (217.136 , 42.672) : ----- 1ES_0229+200 ( 38.202 , 20.287) : ----- BL_Lac (330.680 , 42.278) : 0.368 S5_0716+71 (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_0528+134 ( 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 1959+650. Not significant after trial factor of 28 sources in list.
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)