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Neutrino Astronomy at the South Pole. David Boersma UW Madison “New Views of the Universe” Chicago, 10 December 2005. Cosmic Ray Spectrum. Berezinsky et al, 1985 Gaisser, Stanev, 1985. High Energy neutrinos. Beam-dump model: p 0 g -astronomy p ± n -astronomy.
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Neutrino Astronomy at the South Pole David Boersma UW Madison “New Views of the Universe” Chicago, 10 December 2005
Cosmic Ray Spectrum David Boersma @ New Views of the Universe
Berezinsky et al, 1985 Gaisser, Stanev, 1985 High Energy neutrinos Beam-dump model: p0g-astronomy p±n-astronomy Neglecting g absorption (uncertain) ng Targets: p or ambient g David Boersma @ New Views of the Universe
Neutrino Detection μ νμ W X X’ μ νμ Angle(νμ,μ) ≈ 1° (at E=1TeV) Detected energy deposit by muon gives lower limit for energy of neutrino David Boersma @ New Views of the Universe
νe,τ e,τ W X X’ νμ,e,τ μ,e,τ Z X X’ Neutrino Detection David Boersma @ New Views of the Universe
Optical properties of ice @SP Average optical ice parameters: AMANDA/IceCube ANTARES labs ~ 110 m @ 400 nm labs ~ 60 m @ 470 nm lsca ~ 20 m @ 400 nm lsca ~ 300 m @ 400 nm David Boersma @ New Views of the Universe
ANTARTICA Amundsen-Scott South Pole Station IceCube South Pole Dome road to work AMANDA Summer camp 1500 m Population: Austral Summer: ~240 people Austral Winter: ~60 people David Boersma @ New Views of the Universe 2000 m [not to scale]
IceCube Collaboration • Bartol Research Institute, Delaware, USA • Pennsylvania State University, USA • UC Berkeley, USA • UC Irvine, USA • Clark-Atlanta University, USA • University of Maryland, USA • IAS, Princeton, USA • University of Wisconsin, Madison, USA • University of Wisconsin, River Falls, USA • LBNL, Berkeley, USA • University of Kansas, USA • Southern University and A&M College, Baton Rouge, USA USA (12) Europe (13) Japan New Zealand ANTARCTICA • Universite Libre de Bruxelles, Belgium • Vrije Universiteit Brussel, Belgium • Université de Gent, Belgium • Université de Mons-Hainaut, Belgium • Universität Mainz, Germany • DESY-Zeuthen, Germany • Universität Dortmund, Germany • Universität Wuppertal, Germany • Uppsala university, Sweden • Stockholm university, Sweden • Imperial College, London, UK • Oxford university, UK • Utrecht University, Netherlands • Chiba University, Japan • University of Canterbury, Christchurch, New Zealand David Boersma @ New Views of the Universe
AMANDA AMANDA-A (1996) AMANDA-B10 (1997-1999) • 302 OMs on 10 strings • Ø 120m, 500m tall • DAQ: TDC/ADC (surface) AMANDA-II (2000 – 200x) • 677 OMs on 19 strings • Ø 200m, 500m tall • Trigger rate 80 Hz • Since 2003: TWR David Boersma @ New Views of the Universe
AMANDA-II μ tracks pointing error : 1.5º - 2.5º σ[log10(Eμ/TeV)]: 0.3 - 0.4 coverage: 2π Cascades (particle showers) pointing error: 30º - 40º σ[log10(Ec/TeV)]: 0.1 - 0.2 coverage: 4π cosmic rays (+SPASE) combined pointing err : < 0.5ºσ[log10(Ep/TeV)]: 0.06 - 0.1 Nucl. Inst. Meth. A 524, 169 (2004) energy deposited in OM time recorded on OM David Boersma @ New Views of the Universe
AMANDA research topics • Steady sources of neutrinos • Point sources (AGNi) • Diffuse flux (with muons) • Diffuse flux (with cascades) • Atmosphere (cosmic rays) • Gravitationally trapped WIMPs • Magnetic monopoles • Search for sources with time variability • GRBs • Supernovae • Flaring AGNi David Boersma @ New Views of the Universe
Point source search Combined data from 2000-2003 (livetime 807 days) 3329 (upward going) neutrino events Highest excess: 3.4 sigma (chance probability: 92%) Crab nebula: 10 events, <Nbg>=5.4 (chance probability with 33 source candidates: 64%) David Boersma @ New Views of the Universe
Atmospheric Muons & Neutrinos E deposited≈ Nch Get Eν and Eμ through unfolding David Boersma @ New Views of the Universe
Diffuse flux David Boersma @ New Views of the Universe
The first km3 detector: IceCube 60/OM string 17 m vertical distance Strings in vertices of 125 m-side triangles David Boersma @ New Views of the Universe
LED flasher board main board PMT base 25 cm PMT 33 cm Benthosphere David Boersma @ New Views of the Universe
IceCube construction Jan 2005: 1 string (60 DOMs) + 4/8 tanks/ stations deployed 2005/6 Plan (starting now!) 10-12 strings 24/12 tanks/stations Full detector: 2010 David Boersma @ New Views of the Universe
High Energy muons Eμ= 6 PeV David Boersma @ New Views of the Universe
ContainedHigh Energy Shower E = 375 TeV David Boersma @ New Views of the Universe
High Energy Tau(double bang) E ≈ 10 PeV David Boersma @ New Views of the Universe
Ice is a quiet detection medium (compare: expected ~60kHz per OM in ANTARES) David Boersma @ New Views of the Universe
First IceTop-IceCube coincidence event David Boersma @ New Views of the Universe
Conclusions & Outlook • AMANDA showed the feasibility of High Energy Neutrino astronomy with ice as the detection medium. • IceCube will be the coolest neutrino telescope on Earth. • Maybe extended with acoustic detectors (extension to EHE) David Boersma @ New Views of the Universe
Extra Material • WIMPs • IceTop • GRB • Deployment • Flasher David Boersma @ New Views of the Universe
WIMPs from the Sun c ν χ + χ W+ + W-ν + ν David Boersma @ New Views of the Universe l
WIMP limits David Boersma @ New Views of the Universe
IceTop David Boersma @ New Views of the Universe
IceCube’s First String: January 28, 2005 27.1, 10:08: Reached maximum depth of 2517 m 28.1, 7:00: preparations for string installation start 9:15: Started installation of the first DOM 22:36: last DOM installed 12 min/DOM 22:48: Start drop 29.1, 1:31: String secured at depth of 2450.80 20:40: First communication to DOM David Boersma @ New Views of the Universe
All 60 DOMs David Boersma @ New Views of the Universe