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Neutrino astronomy with AMANDA and IceCube. Per Olof Hulth Stockholm University hulth@physto.se. Short summary of neutrinos for pedestrians. There are three different “families” of leptons Electron neutrino ( e ) and the electron (e - ) Muon neutrino ( ) and the muon ( - )
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Neutrino astronomywithAMANDA and IceCube Per Olof Hulth Stockholm University hulth@physto.se
Short summary of neutrinos for pedestrians • There are three different “families” of leptons • Electron neutrino (e) and the electron (e-) • Muon neutrino () and the muon (-) • Tau neutrino () and the tau (-) • The neutrinos penetrates huge amount of matter without being absorbed • E.g. a 1 MeV neutrino from the sun has an absorption length of 20 light years in lead!! Per Olof Hulth Stockholm university
Some neutrino numbers • The Sun sends every second out 200.000.000.000.000.000.000.000.000.000.000.000.000 (2*1038) neutrinos • At Earth we receive about 40.000.000.000 neutrinos/cm2/second • From Big Bang we have 330 000 000 neutrinos/m3 (Energi 0.0004 eV) but only half a proton • 340 000 000 neutrinos are creataed in our body every day (40K) Per Olof Hulth Stockholm university
Neutrinos from Supernova • When a star explodes 99% of the energy is emitted in neutrinos • A star exploded 1054. Today the Crab nebula Per Olof Hulth Stockholm university
Gamma astronomy Space is nottransparent for High Energy Photons! R. Svensson Zdziarski AA.Ap.J.349:415-28(1990) Kneiski TM, Mannerheim K, Hartmann D.Ap.J. Submitted 2000) Per Olof Hulth Stockholm university
Three open questions in Astrophysics • What is the missing dark matter in the Universe? • What is the origin of the Highest Energy Cosmic rays? • What is powering the Gamma Ray Bursts (GRB)? Per Olof Hulth Stockholm university
You need 20 times more matter to keep the system together than what is observed DARK MATTER !!!! Per Olof Hulth Stockholm university
Most popular model • New type of matter (WIMPs) • Supersymmetric particles from Big Bang • Neutralinos. Per Olof Hulth Stockholm university
WIMPs from Sun/Earth Dark Matter search Look for excess of neutrinos from centre of the Earth and the Sun!! Per Olof Hulth Stockholm university
Cosmic rays proton mesoner muons About 100 muons/m2sek Per Olof Hulth Stockholm university
Cosmic rays Energies up to 50 Joules! What is the process creating these particles??? Per Olof Hulth Stockholm university
A possible candidate for a source for cosmic rays Per Olof Hulth Stockholm university
Gamma Ray Bursts Source 9 Billion light years away! The sources of GRBs on cosmologic distances! The most “violent” objects in the Universe Per Olof Hulth Stockholm university
Gamma Ray Bursts • Could be danger to be too close… Per Olof Hulth Stockholm university
Messengers of Astronomy Only neutrinos cover the whole energy range Per Olof Hulth Stockholm university
Neutrino production If protons are accelerated we expect about equal amount of gammas and neutrino!! Per Olof Hulth Stockholm university
Classes of Models log(E2 Flux) pp core AGN p blazar jet Top-Bottom model Various recent models for transient sources GRB (W&B) 3 6 9 log(E/GeV) TeV PeV EeV Per Olof Hulth Stockholm university
Neutrino astronomy so far • Only two neutrino sources in space has been observed. • The solar neutrinos (Nobel price 2002) • Neutrinos from SN1987 in the Large Magellanic Cloud (180 000 light years) • Energy of neutrinos only 1-30 MeV Per Olof Hulth Stockholm university
Neutrino physics (again) • We have three types of neutrinos: • Electron neutrino ne • Muon neutrino nm • Tau neutrinon nt E.g. Neutron decay : neutron -> proton + e- + ne Per Olof Hulth Stockholm university
Neutrino interaction < 1 degree The muon can travel several km in e.g. ice Per Olof Hulth Stockholm university
Cherenkov radiation A charged particle moving with the speed of light in the medium will generate a shock wave of light q cosq = 1/(nb) b = v/c, n= refraction index Per Olof Hulth Stockholm university
The AMANDA telescope at the South Pole • Why the South Pole? • A 3000 meter thick glaciar • A scientific base with all infra structure • No fishes and no 40K Per Olof Hulth Stockholm university
AMANDA Per Olof Hulth Stockholm university
South Pole Per Olof Hulth Stockholm university
Per Olof Hulth Stockholm university Joakim Edsjö SU
Per Olof Hulth Stockholm university Joakim Edsjö SU
myon neutrino Per Olof Hulth Stockholm university
106 muons from cosmic rays/muon from neutrinos !!!! myon Select only muons from below!!!! neutrino Per Olof Hulth Stockholm university
Hot water heaters -50 m -55 C -25 C -2400 m Per Olof Hulth Stockholm university
Per Olof Hulth Stockholm university Joakim Edsjö SU
-840 m Per Olof Hulth Stockholm university
AMANDA Per Olof Hulth Stockholm university
AMANDA Event Signatures:Muons DATA CC muon neutrino interactions Muon tracks Per Olof Hulth Stockholm university nm + N m + X
Point Sources Amanda II (2000) Skyplot is scrambled in event time for blind analysis, Plot has been released, and results will be available soon. Examples for a few candidates will be given. Equatorial coordinates: declination vs. right ascension. Per Olof Hulth Stockholm university
-45 0 45 90 -90 AMANDA B10 and A-II: some limits and projected sensitivity 10-13 m cm-2 s-1 AMANDA B10 average Sensitivity for sel. soruces Super-Kamiokande To appear in ApJ: astro-ph/0208006 10-14 A-II, limit on SS433 A-II, sensitivity on SS433 MACRO 10-15 SS433* A-II, limit on Mrk 501 A-II projected sensitivity Combined 97-02 Mrk501 (HEGRA 97, n/g=1) Declination (deg) Per Olof Hulth Stockholm university
Amanda Analysis activities • AMANDA-B10 1997 analysis at the end • AMANDA-B10 1999 analysis started • AMANDA-II 2000 filtering done, first analyses started • AMANDA-II 2001 online filtering continuously done In order to do a “blind analysis” only 20% of the data is used for tuning cuts Per Olof Hulth Stockholm university
IceCube!! IceCube has been designed as a discovery instrument with improved: telescope area detection volume energy measurement of secondary muons and electromagnetic showers identification of neutrino flavor angular resolution Per Olof Hulth Stockholm university
The IceCube Collaboration • 11 European, 1 Japanese, 1 South American and 11 US Institutions • (many of them are also AMANDA member institutions) • Bartol Research Institute, University of Delaware, Newark, USA • BUGH Wuppertal, Germany • Universite Libre de Bruxelles, Brussels, Belgium • Dept. of Physics, Chiba University, Japan • CTSPS, Clark-Atlanta University, Atlanta USA • DESY-Zeuthen, Zeuthen, Germany • Imperial College, London, UK • Institute for Advanced Study, Princeton, USA • Dept. of Technology, Kalmar University, Kalmar, Sweden • Lawrence Berkeley National Laboratory, Berkeley, USA • Dept. of Physics, Southern University and A\&M College, Baton Rouge, LA, USA • Dept. of Physics, UC Berkeley, USA • Institute of Physics, University of Mainz, Mainz, Germany • Dept. of Physics, University of Maryland, USA • University of Mons-Hainaut, Mons, Belgium • Dept. of Physics, Pennsylvania State University, University Park, PA, USA • Dept. of Physics, Simon Bolivar University, Caracas, Venezuela • Dept. of Astronomy, Dept. of Physics, SSEC, University of Wisconsin, Madison, USA • Physics Dept., University of Wisconsin, River Falls, USA • Division of High Energy Physics, Uppsala University, Uppsala, Sweden • Fysikum, Stockholm University, Stockholm, Sweden • Dept. of Physics, University of Alabama, Tuscaloosa, USA • Vrije Universiteit Brussel, Brussel, Belgium • Utrecht, Holland (since 29th of October 2002) Per Olof Hulth Stockholm university
Grid North 100 m AMANDA South Pole SPASE-2 Dome Skiway IceCube:Top View 80 strings 60 modules/string Volume 1 km3 Depth 1400-2400 m Counting House Per Olof Hulth Stockholm university
IceTop AMANDA South Pole IceCube Skiway 80 Strings 4800 PMT 1400 m 2400 m Per Olof Hulth Stockholm university
- flavors and energy ranges Filled area: particle id, angle, energy Shaded area: energy and angle. Per Olof Hulth Stockholm university
µ-events in IceCube Eµ=6 PeV Eµ=10 TeV AMANDA-II 1 km Measure energy by counting the number of fired PMT. (This is a very simple but robust method) Per Olof Hulth Stockholm university
1 pp core AGN (Nellen) 2 p core AGN Stecker & Salomon) 3 p „maximum model“ (Mannheim et al.) 4 p blazar jets (Mannh) 5 p AGN (Rachen & Biermann) 6 pp AGN (Mannheim) 7 GRB (Waxman & Bahcall) 8 TD (Sigl) Diffuse Fluxes: Predictions and Limits Mannheim & Learned, 2000 Macro Baikal Amanda IceCube Per Olof Hulth Stockholm university
Compare to Mrk 501 gamma rays Field of view: Continuous 2 p sr (northern sky) AMANDA B10 prelim. limit Sensitivity of 3 years of IceCube Per Olof Hulth Stockholm university
Neutrinos from Gamma Ray Bursts Test signal: 1000 GRB a la Waxman/Bahcall 1999 Expected no. of events: 11 upgoing muon events Expected background: 0.05 events Sensitivity (1000 bursts): 0.2 dN/dE (Waxman/Bahcall 99) Only 200 GRB needed to detect/rule out WB99 flux Per Olof Hulth Stockholm university
Cascade event ne + N --> e- + X The length of the actual cascade, ≈ 10 m, is small compared to the spacing of sensors 1 PeV ≈ 500 m diameter Fully active calorimeter with linear energy resolution Sensitivity for diffused flux about the same as for muons E = 375 TeV Per Olof Hulth Stockholm university
“Double Bang” t + N --> t- + X t + X • E << 1 PeV: Single cascade • (2 cascades coincide) • E ≈ 1 PeV: Double bang • E >> 1 PeV: Second cascade + tau track Per Olof Hulth Stockholm university