XIX European Cosmic Ray Symposium Firenze (Italy) Neutrino Astronomy and Cosmic Rays at the South Pole Latest results from AMANDA and perspectives for IceCube Paolo Desiati University of Wisconsin – Madison

Bartol Research Inst, Univ of Delaware, USA Pennsylvania State University, USA University of Wisconsin-Madison, USA University of Wisconsin-River Falls, USA LBNL, Berkeley, USA UC Berkeley, USA UC Irvine, USA Bartol Research Inst, Univ of Delaware, USA Pennsylvania State University, USA University of Wisconsin-Madison, USA University of Wisconsin-River Falls, USA LBNL, Berkeley, USA UC Berkeley, USA UC Irvine, USA Univ. of Alabama, USA Clark-Atlanta University, USA Univ. of Maryland, USA IAS, Princeton, USA University of Kansas, USA Southern Univ. and A&M College, Baton Rouge Univ. of Alabama, USA Clark-Atlanta University, USA Univ. of Maryland, USA IAS, Princeton, USA University of Kansas, USA Southern Univ. and A&M College, Baton Rouge Universidad Simon Bolivar, Caracas,Venezuela Université Libre de Bruxelles, Belgium Vrije Universiteit Brussel, Belgium Université de Mons-Hainaut, Belgium Universität Mainz, Germany DESY-Zeuthen, Germany Universität Wuppertal, Germany Université Libre de Bruxelles, Belgium Vrije Universiteit Brussel, Belgium Université de Mons-Hainaut, Belgium Universität Mainz, Germany DESY-Zeuthen, Germany Universität Wuppertal, Germany Uppsala Universitet, Sweden Stockholm universitet, Sweden Kalmar Universitet, Sweden Imperial College, London, UK University of Oxford, UK Utrecht University, Utrecht, NL Uppsala Universitet, Sweden Stockholm universitet, Sweden Kalmar Universitet, Sweden Imperial College, London, UK University of Oxford, UK Utrecht University, Utrecht, NL Chiba University, Japan University of Canterbury, Christchurch, New Zealand University of Canterbury, Christchurch, New Zealand Who are we ?

Amundsen-Scott South Pole Station South Pole Dome Summer camp AMANDA road to work 1500 m 2000 m [not to scale] Where are we ?

PMT noise: ~1 kHz AMANDA-B10 (inner core of AMANDA-II) 10 strings 302 OMs Data years: Optical Module “Up-going” (from Northern sky) “Down-going” (from Southern sky) AMANDA-II 19 strings 677 OMs Trigger rate: 80 Hz Data years: >=2000 PMT looking downward

AMANDA IceCube IceTop IceCube 80 strings 60 OMs/string 17 m vertical spacing 125 m between strings IceTop 160 tanks frozen-water tanks 2 OMs / tank First year deployment (Jan 2005) 4 IceCube strings (240 OMs) 8 IceTop Tanks (16 OMs) 10” Hamamatsu R m IceTop Tank deployed in 2004

Event detection in the ice O(km) long  tracks ~15 m cascades Longer absorption length → larger effective volume AMANDA-II  tracks pointing error : 1.5º - 2.5º σ [log 10 (E/TeV)] : coverage : 2  Cascades (particle showers) pointing error : 30º - 40º σ [log 10 (E/TeV)] : coverage : 4  cosmic rays (+SPASE) combined pointing err : < 0.5º σ [log 10 (E/TeV)] : Nucl. Inst. Meth. A 524, 169 (2004) event reconstruction by Cherenkov light timing South Pole ice:ice the most transparent natural medium ? a neutrino telescope    0.65 o  (E /TeV) (3TeV<E <100TeV)  ab s > ~ nm  sca > ~ nm

ν astronomy : physics goals Bottom-Up scenario cosmic accelerator p + (p or  )    + X  e,  + X Protons which escape are bent => cosmic rays Photons which escape are absorbed above 50 TeV Neutrinos escapeNeutrinos a neutrino telescope good pointing resolution good acceptance AMANDA IceCube Array requires ~ km 3 scale

ν astronomy : background Background rejection Cosmic ray μ main background Protons which escape are bent => cosmic rays Photons which escape are absorbed above 50 TeV Neutrinos escape Up/DownEnergy Source direction Arrival time Count rates Atmospheric ν × Diffuse ν, Cascades, UHE events ×× Point sources: AGN, WIMPs ××× GRB ×××× Supernovae × Preliminary

ν astronomy : background Atmospheric  background & calibration beam First energy spectrum > 10 TeV Blobel regularized unfolding Protons which escape are bent => cosmic rays Photons which escape are absorbed above 50 TeV Neutrinos escape Preliminary Expected high energy  flux … in this talk  telescope capability search of high energy  from extra-terrestrial steady point sources Cosmic Ray measurements

telescope : point source search Detection of  from discrete steady bright or close sources (AGN, …) cosmic ray  background rejection good pointing resolution bin search optimization versus a given signal (  E -2 ) detector pointing resolution bin search radius  effective area AMANDA-B103° ↑ -5.8° → 5°  5° (min) 10°  10° (max) ~0.01 km TeV AMANDA-II1.5° ↑ -2.7° → 3.6°  3.6° (min) 8.8°  8.8° (max) ~0.025 km 2 10 TeV) IceCube~0.7° (> 10 TeV) (> 10 TeV ~ 1° ~ 0.8 km 2 (> 10 TeV) ~1.2 km 2 (> 100 TeV) AMANDA-B10  0 o  0 o  0 o  0 o  effective area 1 m 2  AMANDA-II  declination  0 o   90 o  ↑  2

telescope : point source search Average upper limit = sensitivity (δ>0°) (integrated above 10 GeV, E -2 signal) (*) optimized for E -2, -3 signal 1997 : Ap.J. 583, 1040 (2003) 2000 : PRL 92, (2004) IceCube IceCube : Astrop Phys 20, 507 (2004) average flux upper limit [cm -2 s -1 ] sin  AMANDA-B10 AMANDA-II Sensitivity independent of direction *  lim  0.68·10 -8 cm -2 s -1 average flux upper limit [cm -2 s -1 ] sin  AMANDA-B10 AMANDA-II IceCube 1/2 year * Preliminary  declination  0 o   90 o 

telescope : point source search from northern hemisphere 3438  expected from atmosphere Preliminary Search for clustering in northern hemisphere compare significance of local fluctuation to atmospheric  expectations un-binned statistical analysis no significant excess ~92% Maximum significance 3.4  compatible with atmospheric  also search for neutrinos from unresolved sourcesalso search for neutrinos from unresolved sources

Cosmic rays spectrum

1 km 2 km Cosmic rays spectrum SPASE-AMANDA  combined angular resolution ~ 0.5 o  absolute pointing calibration < 1 o  S(30)  N e particle density at 30m from core  K50   energy lost in AMANDA (E  >500GeV )  N  lateral distr func at 50m from core K50,S(30)  (N , N e )  (Energy, Mass) SPASE as muon survey of AMANDA SPASE-2 + AMANDA ~1/7000 km 2 sr for coincident tracks IceTop + IceCube 1/3 km 2 sr for coincident tracks IceTopIceTop-IceCube VETO  All downward events E  > 300 TeV with trajectories inside IceTop  Larger events falling outside CALIBRATION  of angular response and with tagged  Expect ~100 tagged air showers/day with multi- TeV m’s in IceCube IceTop as muon survey of IceCubez S(30) K50

Cosmic rays composition spectra steeper because of smaller fluctuations at higher energies mean values shifted by fluctuations error in mass determination knee are South Pole IceTop/IceCube energy extension e.g SPASE e.g. KASCADE eV AMANDA-B10 Normalize to direct measurements = 2 (JACEE/RUNJOB)JACEE/RUNJOB SPASE-AMANDA Primary energy resolution ~ 0.07 in log 10 (E prim ) CR composition measured in PeV IceTop-IceCube Covers sub-PeV to EeV energies Improve energy resolution

Cosmic rays composition In press Astroparticle Physics mass-independent high resolution primary energy measurement probing relative change of muonic energy to electromagnetic energy in the shower method robust against systematic uncertainties data are consistent with an increase of cosmic ray mass composition at the knee, between 500 TeV and 5 PeV. Direct measurements

Summary AMANDA-II is collecting data and increasing statistics. Has reached good sensitivity as neutrino telescope (point sources search) SPASE-2/AMANDA-B10 indicates increase of CR mass knee AMANDA-II is improving other results by tightening constraints on models : Neutrinos from SN Neutrinos from WIMP annihilations (Earth and Sun) Search for neutrinos in coincidence with GRB’s Search for neutrinos    e  from unresolved diffuse sources Search for UHE/EHE extra-galactic neutrinos CR spectrum and composition IceCube/IceTop will significantly improve astrophysics in energy range and resolution IceCube will be a powerful all-flavor neutrino detector (particle physics)particle physics IceTop will open the CR measurements up to ~ EeV with high resolution AMANDA will overlap the lower energy tail of IceCube sensitivity

“The South Pole thank you

Polar ice optical properties Measurements: ►in-situ light sources ►atmospheric muons Average optical ice parameters: abs ~ nm sca ~ nm att ~ nm Scattering bubbles dust Absorption dust ice back

Mediterranean sea optical properties Average optical ice parameters: abs ~ nm sca ~ nm att ~ nm back abs att Average values 2850÷3250 m

AMANDA : neutrino limits diffuse (B10) cascades /3 UHE/3 Unfolded (last bin) constraint models Upper limits on diffuse ET neutrino fluxes Atmospheric ν energy spectrum Cascade analysis Ultra High Energy ν search back Antares 1 yr IceCube 1 yr

AMANDA :  Aeff AMANDA-B10 AMANDA-II back

AMANDA : K50 The entire high energy (> 500 GeV) muon bundle is measured over a large volume The light output from all muons is sampled over 500 m length and 150 m laterally K50 is the measure of muon energy lost in a large volume back

AMANDA : K50 normalization back Apanasenko et al., Astrop. Phys. 16, 13 (2001)

CR composition: fluctuations back SPASE/IceTop KASCADE(-Grande)

CR composition: fluctuations back J. Van Buren Diploma Thesis Karlsruhe, 2002

back IceTop : EAS detection Small showers (2-10 TeV) associated with the dominant  background in the deep detector are detected as 2-tank coincidences at a station. Detection efficiency ~ 5% provides large sample to study this background Showers triggering 4 stations give ~300 TeV threshold for EAS array Large showers with E ~ PeV will clarify transition from galactic to extra-galactic cosmic rays.

IceTop back Rates of contained coincident events 125 m grid, km 2 air shower array at 690 g/cm 2 E threshold ~ 300 TeV for > 4 stations in coincidence Useful rate up to ~ EeV Total rate 1-2 kHz Median E primary = 3.5 TeV Small showers trigger station if within ~30 m Direct tag for few % of muon background (~50 Hz out of 1-2 kHz)

IceTop : EeV detection back  Penetrating muon bundle in shower core Incident cosmic-ray nucleus Threshold ~ eV to veto this background Potential to reject this background for EeV neutrinos by detecting the fringe of coincident horizontal air shower in an array of water Cherenkov detectors (cf. Ave et al., PRL 85 (2000) 2244, analysis of Haverah Park)

Neutrino flavor identification back Neutrino flavor Log(ENERGY/eV) e e   supernovae Full flavor ID Showers vs tracks AMANDA flavor ID IceCube flavor ID, direction, energy IceCube triggered, partial reconstruction Tau Neutrinos: Regeneration: earth quasi- transparent to  Enhanced  & cascade flux due to secondary , e to the end

IceCube :  Aeff & resolution Galactic center back

NEMO :  Aeff & resolution back Up-going muons with E -1 spectrum 60 kHz background Reconstruction + Quality Cuts Nemo20m 140 (5832 OM) Lattice (5600 OM) From Neutrino 2004 talk by P. Piattelli

IceCube : simulated  track events back E µ =6 PeV, 1000 hitsE µ =10 TeV, 90 hits

IceCube : sensitivities Diffuse   sensitivityPoint source   sensitivity back

IceCube : DOM Mainboard back 2xATWD FPGA Memories HV Board Interface CPLD FPGA (Excalibur/Altera) reads out the ATWD handles communications time stamps waveforms system time stamp resolution 7 ns wrt master clock FPGA (Excalibur/Altera) reads out the ATWD handles communications time stamps waveforms system time stamp resolution 7 ns wrt master clock oscillator (Corning Frequency Ctl) running at 20 MHz maintains df/f < 2x four-channel ATWDs Analog Transient Waveform Digitizers low-power ASICs recording at 300 MHz over first 0.5ms signal complexity at the start of event 2 four-channel ATWDs Analog Transient Waveform Digitizers low-power ASICs recording at 300 MHz over first 0.5ms signal complexity at the start of event Dynamic range  200 p.e./15 ns  2000 p.e./5 ms energy measurement (TeV – PeV) Dead time < 1% fast ADC recording at 40 MHz over 5 ms event duration in ice back