KM 3 Neutrino Telescope European deep-sea research infrastructure DANS – symposium Maarten de Jong

 p travel time bending cosmic rays astronomy absorption space travel Astro-Particle Physics

Energy spectrum of cosmic rays E [eV/particle] flux [(m 2 sr s GeV) -1 ] per km 2 / year 1 per m 2 / second plateau 1.5 eV = kg 1 m LHC

Cosmic particle accelerator? radio images April 1993 – June 1998 V ~ km/s charged particle SN1993J – M81 V interstellar matter time

Which particles? electronsprotons N  p   p neutrinos muons astronomy cosmic rays Synchroton radiation inverse Compton scattering e e

p ++ p ++ ambient light 00 n   Neutrino telescope: – origin cosmic rays – creation & composition of relativistic jets – mechanism of cosmic acceleration black hole

“CERN in the sky” Neutrino astronomy

1960 Markov’s idea:  range of muon  detect Cherenkov light  transparency of water Use sea water as target/detector

How? muon wavefron t ~few km ~100 m muon travels with speed of light (300,000 km/s) → ns – km neutrino interaction

Antares prototype completed May M€

position → time → 100 ms data filter 2  s offline reconstruction 1 Mb/s determination of muon direction 1 GB/s track optical background ~ 100 kHz ~5 neutrinos / day “All-data-to-shore” concept

rate [Hz] cos  neutrinos! Neutrinos? muon  d(  ) Earth

2 May :29

30 March :10

Neutrino sky map 2° Limits on neutrino fluxes, world’s best for some specific sources. part of sky invisible to Antares PSF

KM3NeT Next generation neutrino telescope 200 ‒ 250 M€

Architecture light detection data transmission data filter filtered data neutrino detector shore station analysis operation start stop 100 km ≥ 2.5 km > 1000 km

31 x 3” PMT concentrator ring increase of photocathode area by 20‒40% Optical module

6 m Mechanical cable connection Data cable storage Mechanical cable storage Frame Optical module Mechanical holder Storey 1Digital Optical Module=Dom 2Dom’s on 1 bar=Dom-bar 20Dom-bar’s on 1 tower=Dom tower

sudden Eddie currents Temperature Earth & Sea sciences France observatory food supply Bioluminescence short lived (rare) events dominate deep-sea life permanent observatory time profile

KM3NeT deep-sea infrastructure  10 km 3 ‒> 400,000 PMTs, hydrophones, ACDP, seismometers, etc. ‒< 100 kW, 100 GB/s  two main electro-optical cables ‒100 km, DC, 1 cupper conductor + sea return  network ‒passive, point-to-point optical fiber with amplification ‒new Ethernet standard Precision-Time-Protocol (”White Rabbit”)  operation ‒24h/day, 365 days/year ‒10 years without maintenance

10kHzx400,000=4GHz 310kHzx13,000=4GHz 0.5kHzx1=500Hz neutrinos10 -3 Hz point source10 -7 Hz signal / noise

data filter time Ethernet switch off-shore on shore CPU data flow

data filter time Ethernet switch off-shore on shore CPU data flow

data filter time Ethernet switch off-shore on shore CPU data flow

Data issues  operation of infrastructure – real-time computing computer farm (‘Tier 0’) – control data, QA/QC information, etc. database (Oracle)  offline analysis – distributed data processing Grid/batch computing  Monte Carlo simulations – photon tracking CPU intensive GPU (80 x faster than CPU)  data analyses – ROOT histograms, n-tuples, trees, introspection, etc. high performance I/O

Summary & outlook  Neutrino astronomy is an emerging field at the intersection of particle physics and traditional astronomy ‒several neutrino detectors operational world wide, in Europe, Antares prototype completed in 2008  Deep-sea is actively explored for large research infrastructures – construction of KM3NeT is planned for the coming years – synergy between different sciences – interesting data challenges