6 th Cracow Epiphany Conference http amanda uci

6 th Cracow Epiphany Conference http: //amanda. uci. edu http: //icecube. wisc. edu The AMANDA – Ice. Cube telescopes & Dark Matter searches B. Baret on behalf of the Ice. Cube collaboration Vrije Universiteit Brussel, Belgium bruny. baret@vub. ac. be B. Baret Vrije Univertsiteit Brussel

Physics Motivations and Goals Attractive astronomical messengers: • Transparent Universe (≠g) • Travel in straight line (≠p) • Produced in hadronic accelerators ? Study of: Sources: AGNs, SNRs, GRBs. . . -physics (atmospheric production): Oscillations, cross-sections. . “new” physics: WIMPS, decoherence, monopoles. . . AMANDA Ice. Cube B. Baret Vrije Univertsiteit Brussel

The Ice. Cube collaboration USA: Bartol Research Institute, Delaware Univ. of Alabama Pennsylvania State University UC Berkeley UC Irvine Clark-Atlanta University Univ. of Maryland IAS, Princeton University of Wisconsin-Madison University of Wisconsin-River Falls LBNL, Berkeley University of Kansas Southern University and A&M College, Baton Rouge Sweden: Uppsala Universitet Stockholm Universitet UK: Imperial College, London Oxford University Netherlands: Utrecht University Germany: Universität Mainz DESY-Zeuthen Universität Dortmund Universität Wuppertal Humboldt Universität, Berlin Belgium: Université Libre de Bruxelles Vrije Universiteit Brussel Universiteit Gent Université de Mons-Hainaut Japan: Chiba University New Zealand: University of Canterbury B. Baret Vrije Univertsiteit Brussel

Where are we ? Ice. Cube Amanda North Here! (South pole) Amundsen-Scott South Pole Station Technically North also B. Baret Vrije Univertsiteit Brussel

Detection principle O(km) long tracks South Pole Ice properties (@400 nm): Scattering: ~20 m Pointing res. ( ~2° , casc. ~35°) Absorption: ~110 m Effective volume O(10 m) cascades e, t atm. E. T. Background (x E. T. events/year): atmospheric O(109) atmospheric O(103) p B. Baret Vrije Univertsiteit Brussel

Layout Amanda: Ø=200 m, h=500 m (0. 02 km³) Amanda B-10: 302 Optical Modules (OMs) on 10 strings (9799) Amanda II: 677 OMs on 19 strings (00 ->) Ice. Cube: 1 km x 1 km² instrumented volume 4800 Digital Optical Modules (DOMs) on 80 strings Ice. Top(air shower array): 1 km² instrumented area 160 surface water tanks with 2 DOMs each B. Baret Vrije Univertsiteit Brussel

Ice. Cube Deployment Hot water drilling: 2450 m deep straight within 1 m 35 -40 hrs per hole January 2005: First string deployed 60 DOMs installed (and working!) B. Baret Deployment: 2 more strings up to now Expected completion in 2 Vrije Univertsiteit Brussel

Ice. Cube First Events! Down going Ice. Top tanks Ice. Top – Ice. Cube String 21 B. Baret Vrije Univertsiteit Brussel

Sensitivity and limits Diffuse search E-2 flux hypothesis νe (cascades B 10 1 yr) νμ (A-II 4 yr) Steady point sources sensitivity: all-flavor limits νe+νμ+ντ (UHE B 10 1 yr) νe+νμ+ντ (cascades A-II 1 yr) νe+νμ+ντ (UHE A-II 1 yr) WB bound Icecube (1 yr) average flux upper limit [cm-2 s-1] νμ (B 10 1 yr) * AMANDA-B 10 AMANDA-II Ice. Cube 1/2 year Limit Sensitivity sin B. Baret Vrije Univertsiteit Brussel

Point sources Sky map (00'-03') 3329 Significance maps real sky scrambled sky no source No point source detected so far. . . B. Baret Vrije Univertsiteit Brussel

Neutralino as dark matter candidate Cosmological observations m ~ 0. 30 b ~ 0. 05 � $ dark, non-baryonic matter Minimal Supersymmetric Standard Model PR conserved LSP stable = neutralino = interacts weakly Ge. V-Te. V mass stable B. Baret = dark matter? ? ? Vrije Univertsiteit Brussel

Neutralino capture by Sun and Earth Sun – direct capture from galactic DM halo Earth – capture by gravitational diffusion and weak scattering B. Baret Vrije Univertsiteit Brussel

Which WIMP signal Neutralino-induced neutrinos qq l+l- W, Z, H “up” Atmospheric background atm. : absorbed by the Earth compare on/off source angular regions B. Baret “down” Vrije Univertsiteit Brussel

Data and Monte Carlo used Data 1997 -1999: 5. 0 x 109 events 2001: 8. 7 x 108 events 536. 6 days eff. livetime 143. 7 days eff. livetime Monte Carlo neutralino: 50 Ge. V < M < 5000 Ge. V [DARKSUSY] hard (W+W-) and soft (bb) ann. channel 90° < < 113° (Sun) ~ 180° (Earth) atm. : [CORSIKA] atm. : [ NUSIM ] Sun: 32 days Earth: 128 days 600 Ge. V < Ep < 1011 Ge. V 0° < p < 90° Sun: 2. 104 evts 10 Ge. V < E < 108 Ge. V B. Baret Earth: 2. 108 evts 80° < < 180° Vrije Univertsiteit Brussel

Rejection of signal & background Earth 1997 -1999 (paper in preparation) B. Baret Sun 2001 (submitted to Astrop. Phys. ) Vrije Univertsiteit Brussel

No excess of neutralinoinduced neutrinos Earth 1997 -1999 (paper in preparation) Sun 2001 (submitted to Astrop. Phys. ) signal region B. Baret Vrije Univertsiteit Brussel

Muon flux limits – Earth ’ 97 -’ 99 Improvements (wrt. ’ 97) separate filter for each neutralino mod more statistics PAPER IN PREPARATION B. Baret Outlook 2001 -2003 data set improved reconstructions new trigger lowers Ethresh Vrije Univertsiteit Brussel

AMANDA results submitted for publication Muon flux limits - Sun 2001 1 st AMANDA solar neutralino results 200 m diameter enables robust reconstruction of horizontal tracks Outlook 2000 -2003 data set improved reconstructions new trigger lowers Ethresh B. Baret Vrije Univertsiteit Brussel

Conclusion & outlook AMANDA & Ice. Cube: Amanda provided very useful information (ice, drilling, detection strategy, bkgd, . . . ) providing tighter and tighter constraints on models Ice. Cube all flavour detection, ~30 x more sensitive almost guaranteed discoveries Is being deployed and takes data WIMPs search: No statistically significant excess of neutralino-induced neutrinos from the center of the Earth or the Sun observed Upper limits on the muon flux competitive with other indirect searches Additional data are being analysed with improved techniques B. Baret Vrije Univertsiteit Brussel

B. Baret Vrije Univertsiteit Brussel

Technically Amanda Ice. Cube Optical Module Digital Optical Module 10” PMT +Main Board +flasher 8” PMT Trigger, Digitization, HV Surface single p. e. time res. ~4 -8 ns 32 µs range noise: ~1 k. Hz Digitized Waveform B. Baret Vrije Univertsiteit Brussel DOM time res. <2 ns 400 ns and 6. 4µs range 3 gains noise ~700 Hz

Plan. . . Season planning: Nov. : preparation Dec. : construction Jan. : construction Feb. : commissioning This austral summer : 8 to 12 strings deployed By 2010 : 1 km³ instrumented B. Baret Vrije Univertsiteit Brussel