IceCube and AMANDA: Neutrino Astronomy at the South Pole Brennan Hughey February 22nd, 2007

Questions High Energy Neutrino Astronomy Can Help Address Cosmic ray acceleration sites?Cosmic ray acceleration sites? –TeV gamma-ray sources? –Gamma-ray bursts? “GZK” cutoff?“GZK” cutoff? Dark matter? Supersymmetry?Dark matter? Supersymmetry? What’s out there that we haven’t even conceived of yet?What’s out there that we haven’t even conceived of yet?

Neutrino interacts with particle in ice Secondary particles emit Cherenkov radiation which is detected by optical modules

Dark sector AMANDA IceCube Skiway South Pole Station Geographic South Pole

Backgrounds Preliminary AMANDA 2000 Downgoing Atmospheric Muons - Several million events per day - Cascade events separated by topology - Muon events separated by direction (therefore constrained to northern sky) Atmospheric neutrinos - Can penetrate Earth - Distinguished from Astrophysical neutrinos by energy spectrum - Useful as a calibration tool Downgoing events from Atmosphere Upgoing events through Earth

PMT noise: ~1 kHz AMANDA-B10 (inner core of AMANDA-II) 10 strings 302 OMs Data years: Optical Module AMANDA-II 19 strings 677 OMs Trigger rate: 80 Hz Data years: The AMANDA Detector Antarctic Muon And Neutrino Detector Array

Example Analysis: GRBs Most violent explosions in universe: ~10 51 ergs Durations from milliseconds to thousands of seconds In bimodal distribution Occur isotropically in space – extragalactic in origin Beamed emission – reduces energy requirement per burst but increases total number of bursts

Neutrinos from GRBs  + p →  + →  + →  + +  → e + + e +  +  Prompt Emission [1,2,3] Afterglow Emission [4] Precursor Emission [5] Models of summed neutrino emission from one year of bursts High energy neutrinos produced in relativistic jets [1] E. Waxman and J. Bahcall, Phys. Rev. Lett. 80, [2] K. Murase and S. Nagataki, Physical Review D 73, [3] S. Razzaque, P. Meszaros and E. Waxman Phys. Rev. Lett. 90, [4] S. Razzaque, P. Meszaros and E. Waxman Physical Review D, 68, [5] E. Waxman and J. Bahcall, Astrophysics Journal 541,

10 min Blinded Window -1 hour +1 hour AMANDA GRB Searches Background is measured off-time at location of burst 10 minute window is kept blinded, but time examined for neutrino signal is T 90 +U 90 +1s. Searches performed in coincidence with 312 BATSE and 91 IPN bursts Separate cascade channel search performed with 73 BATSE bursts Precursor search performed for Untriggered search performed in Individual burst modeling for GRB & GRB980703A

Flux Limits (Limits show 90% energy ranges) Preliminary

significance map AMANDA II data from (1001 live days) 4282 from northern hemisphere No significant excess observed Highest excess: 17 events on a background of 5.8 events Time scrambled Data Point Source Search

Diffuse Limits

Other AMANDA Analyses Supernova monitoring Ultra-High Energy searches Galactic plane search Cosmic ray composition (with SPASE) Dark matter (WIMP) Searches Magnetic Monopoles Searches for exotic physics (Lorentz invariance etc) AMANDA-II AMANDA-B10 IceCube 30 kpc

IceTop InIce Air shower detector Threshold ~ 300 TeV planned 80 strings of 60 optical modules 17m between modules 125m string separation 1km 3 instrumented volume : 1 string : 8 strings AMANDA 19 strings 677 modules Completion by : 13 strings deployed IceCube First data in 2005 first upgoing muon: July 18, 2005 Altogether: 22 strings 52 surface tanks

Ice-top CoincidenceNeutrino CandidateEnergetic Downgoing Muon

Drilling and Deployment

Conclusions AMANDA currently has best limits on fluxes of high energy neutrinos AMANDA continues to take data and will operate as a sub-array within IceCube IceCube is more than 1/4 complete and construction is on track IceCube will have an effective area two orders of magnitude larger than AMANDA – Discovery instrument

Backup

 signature  signature eV (10 TeV) ~90 hits 6x10 15 eV (6 PeV) ~1000 hits Multi-PeV   +N  +...  ± (300 m!)   +hadrons AMANDA Event Signatures in IceCube

in AMANDA in IceCube Simulated 2×10 19 eV neutrino event

Hose reel Drill tower IceTop tanks

Photomultiplier tube Mu metal magnetic shield Glass sphere PMT base Mainboard

Measurements: in-situ light sources atmospheric muons Dust Logger Average optical ice parameters : abs ~ nm sca ~ nm Scattering Absorption optical WATER parameters : abs ~ nm sca ~ nm

Better Pointing Resolution Larger Effective Area Muon-neutrino CC interactions Half-sky coverage Better Energy Resolution Better Background Rejection All Flavor Detection Full-sky coverage Two Detection Channels Muon ChannelCascade Channel

Neutralino-induced neutrinos qq  l + l -   W, Z, H “downgoing” “upgoing” Searches for WIMPS with AMANDA Weakly Interacting Massive Particles - Leading dark matter candidate - Collect in center of sun and Earth - May produce > 10 GeV neutrinos through WIMP-antiWIMP annihilation

Limits on muon flux from EarthLimits on muon flux from Sun Solar and Earth WIMP Limits

Bursts of low-energy (MeV) ν e from SN simultaneous increase of all PMT count rates (~10s) Since 2003: AMANDA supernova system includes all AMANDA-II channels Recent online analysis software upgrades –can detect 90% of SN within 9.4 kpc Part of SuperNova Early Warning System (with Super-K, SNO, LVD, …) AMANDA-II AMANDA-B10 IceCube 30 kpc Supernova Search

event selection optimized for both dN/dE ~ E -2 and E -3 spectra source nr. of events (5 years) expected background (5 years) flux upper limit  90% (E >10 GeV) [10 -8 cm -2 s -1 ] Markarian M ES SS Cygnus X Cygnus X Crab Nebula C2738(1yr)4.72(1yr)0.99 No significant excess observed Search for neutrinos from interesting sky spots crab Mk421 Mk501 M87 Cyg-X3 1ES1959 Cyg-X1 SS433 3C273

SPASE/AMANDA 12° SPASE AMANDA x= m y= m z= m South Pole Air Shower Experiment Uses surface air shower array in coincidence with AMANDA as a muon detector in order to determine Composition and energy of cosmic rays

IceCube and AMANDA collaborations merged, March 2005 AMANDA/IceCube Collaboration USA: Bartol Research Institute, Delaware Pennsylvania State University UC Berkeley UC Irvine Clark-Atlanta University University of Maryland University of Wisconsin-Madison University of Wisconsin-River Falls Lawrence Berkeley National Lab. University of Kansas Southern University and A&M College, Baton Rouge University of Alaska, Anchorage Sweden: Uppsala Universitet Stockholm Universitet UK: Oxford University Netherlands: Utrecht 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 zu Berlin MPI Heidelberg RWTH Aachen Japan: Chiba university New Zealand: University of Canterbury