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Neutrino Astronomy. @ South Pole. AMANDA & IceCube. Why Neutrino ?. High energy photons are absorbed beyond ~ 150Mpc g HE g LE e - e + HE n s are unique to probe HE processes in the vicinity of cosmic accelerators HE Cosmic Rays and n s may have the same origin.
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Neutrino Astronomy @ South Pole AMANDA & IceCube
Why Neutrino ? • High energy photons are absorbed beyond ~ 150Mpc • gHE gLEe-e+ • HE ns are unique to probe HE processes in the vicinity • of cosmic accelerators • HE Cosmic Rays and ns may have the same origin
Cosmic Neutrino Factories Most models assume a central black-hole and accretion disk. Particle acceleration occurs either near the black hole or in the jet p + p() p0 + p + ... ggnmm nm ne e
nm + N m+ X Detection Principle neutrino Astrophysical Sources muon Neutrino interacts in ice surrounding the detector Muon track is reconstructed by mapping the Cherenkov photon times recorded by the Optical Modules
AMANDA Detector @ South Pole Antarctica • 677 OMs • on 19 strings • since Jan 2000
AMANDA Event Signatures:Muons CC muon neutrino Interaction track nm + N m +X
1 km 0.02 0.1 0.5 Scattering coefficient (1/m) vs. depth 2 km 1 km deep and shallow ice for future IceCube IceCube
Source\Sensitivity muon (10-15 cm-2 s-1) n(10-8 cm-2 s-1) Markarian 421 1.8 1.1 Markarian 501 1.8 1.1 Crab 2.7 1.3 Cass. A 1.6 1.2 SS433 5.9 2.4 Cyg. X-3 1.7 1.1 Point Sources Amanda II (2000) 1129 events • Improved coverage near horizon • Sensitivities calculated using background levels predicted from data • close to “/~ 1 sensitivity” for some sources Event times scrambled for blind analysis purposes. PRELIMINARY
IceTop AMANDA • 1 station on top of each IceCube string • 2 ice tanks per station • 2 DOMs in each tank • IceTop will detect Air Showers • of energies 1014 eV to 1018 eV South Pole Skiway • 4800 PMT • Instrumented volume: 1 km3 (1Gt) • 80 Strings • IceCube is designed to detect neutrinos of all flavors at energies from 107 eV to 1020 eV 1400 m IceCube 2400 m
Construction: 11/2004-01/2010 Grid North 100 m AMANDA South Pole SPASE-2 Dome IceCube Skiway
Self-triggers on each pulse Captures waveforms Time-stamps each pulse Digitizes waveforms Performs feature extraction Buffers data Responds to Surface DAQ Set PMT HV, threshold, etc Digital Optical Module - (DOM) DOM 33 cm
IceCube String Main Cable 60 optical sensors DOM Base with HV 1400 m generator Electrical feedthrough for power + data OM Spacing: 17 m Photomultiplier DOM Board Gel Glass pressure String sphere. Rated to 10000 psi. Outer diameter: 13" 2400 m
Two functions veto and calibration cosmic-ray physics Energy range: ~3 x 1014 -- 1018 eV few to thousands of muons per event Measure: Shower size at surface High energy muon component in ice Large solid angle One IceTop station per hole ~ 0.5 sr for C-R physics with “contained” trajectories Larger aperture as veto IceTop Coincident events
µ-event in IceCube300 atmospheric neutrinos per day AMANDAII IceCube: -> Larger telescope -> Superior detector 1 km