High energy neutrino astronomy with the ANTARES Cherenkov telescope P.Vernin CEA/Irfu/SPP On behalf of the ANTARES collaboration IWARA 2009 Conference Maresias, Sao Paulo, Brazil, 4-8/10/2009 i r f u saclay
The history of the sky survey The PHOTON since the origins Extension to the non visible since tens of years (Radio, IR, UV, X and gamma) Satellites tens of GeV Large arrays tens of TeV Multi-wavelenth PHOTON astronomy Paulo, Brazil 2
Cosmic ray spectrum 25 J Paulo, Brazil 3
High energy neutrinos The neutrino as an alternative solution Multi-wavelength and multi-messenger studies Exploration of the most remote regions of the Universe Not absorbed (weak cross section) Electrically neutral: not deflected by magnetic fields But at least a km 3 is necessary! Paulo, Brazil 4
Neutrino is a UniqueMessenger Three possible messengers: photons, protons, neutrinos absorption cut-off mean free path -rays: + 2.7k >10 14 ev 10 Mpc proton: p + 2.7k 0 + X >5.10 19 ev 50 Mpc neutrinos: + 1.95K Z+X >4.10 22 ev (40 Gpc) galactic magnetic deflection (B=2 G, Z=1, L=1kpc) =12 o deg @ 10 19 ev Paulo, Brazil 5
The mechanism Synchrotron radiation followed by Compton scattering HE electron LE Paulo, Brazil 6
The mechanism Synchrotron radiation followed by photo-production HE electron LE Paulo, Brazil 7
The mechanism Synchrotron radiation followed by photo-production HE electron LE L L Paulo, Brazil 8
Scientific issues Astrophysics Quasars Active galaxy nucleus (AGN) Gamma ray bursts (GRB) Microquasars Pulsars SNR Topological defects + other exotics Particle physics and Cosmology DM indirect search Neutrino oscillations Paulo, Brazil 9
Difficult detection Very weak cross section Huge detector km 3 Very high atmospheric muon flux shielded detector Underground or submarine Paulo, Brazil 10
Detection techniques HE induced muon produced in the surrounding medium by HE neutrino Upward-going neutrinos only (2 ) Mass = R S (R 2.5 km water equivalent @ 1 TeV; 10 km @10 TeV) HE muons produced inside the detector by HE neutrino interactions (4 ) Requires a very large detector (IceCube or KM3NeT) VHE e interaction inside the detector (4 ) Detection of cascades Paulo, Brazil 11
Induced muons p The cherenkov light is detected by the PMTs detector c=43 The muon generates the Cherenkov light The neutrinos interact With the surrounding matter Correlation time-position direction of the muon Precision on the position: 10cm Paulo, Brazil 12 Precision on time: 1ns
The advantages Target mass energy R increases with the neutrino Interaction cross section increases with the neutrino energy Detection efficiency increases with the muon energy and therefore with the neutrino energy Enrichment of the high energy neutrinos Paulo, Brazil 13
Physics background Atmospheric showers atmospheric muons 10 9 events/year Atmospheric neutrinos 3000/year d /d cm -2 s -1 sr -1 Atm. muons 2400 m depth, E > 1 TeV 10 6 Atm. cos Paulo, Brazil 14
The neutrino telescopes ANTARES La-Seyne-sur-Mer, France BAIKAL: Baikal lake, Siberia NEMO Catania, Italy NESTOR : Pylos, Greece DUMAND, Hawaii (cancelled 1995) P.Vernin, AMANDA, IWARA 2009, IceCube Mresias, Sao Paulo, Brazil 15 South Pole
The ANTARES Collaboration NIKHEF, Amsterdam KVI Groningen NIOZ Texel ITEP,Moscow University of Erlangen IFIC, Valencia UPV, Valencia CPPM, Marseille DSM/IRFU/CEA, Saclay APC Paris IPHC (IReS), Strasbourg Univ. de H.-A., Mulhouse IFREMER, Toulon/Brest C.O.M. Marseille LAM, Marseille GeoAzur Villefranche University/INFN of Bari University/INFN of Bologna University/INFN of Catania LNS Catania University/INFN of Pisa University/INFN of Rome ISS, Bucarest P.Vernin, IWARA 2009, University/INFN Mresias, Sao of Genova Paulo, Brazil 16
The Antares station Submarine cable -2475m La Seyne sur Mer Onshore station Michel Pacha institute Paulo, Brazil 17
The control room Paulo, Brazil 18
The ANTARES detector 2500m depth Storey 350 m 45 14.5 m Cable to shore 100 m Junction Box ~60 m vincenzo flaminio Link cable Paulo, Brazil 19
Background light Example: 3 OMs of 1 floor over 2 minutes 35-40 khz from K40 and dark current About 20 khz from bacteria (?) Occasional bursts, related to sea current Paulo, Brazil 20
Number of Triggers 5 lines (2007) 19.10 6 μ 10 or more lines (2008) 65.10 6 μ CABLE REPAIR Total : 240 days = 80% of calendar Selected :167d = 70% of total Total : 243 days = 83% of calendar Selected :173d = 71% of total Paulo, Brazil 21
Zenith angular distribution June 2007 Dec 2008 neutrinos 5+10+12 lines 341 active days 1062 upward neutrino candidates upgoing downgoing Paulo, Brazil 22
Search for point-like sources Upper limits obtained with 2007 data (5 lines, 140 day lifetime), compared with 1 year of complete detector (12 lines) and other experiments Analysis of 12-line data is ongoing Paulo, Brazil 23
5 lines (2007): Depth vs. Intensity 2,5km 6km Paulo, Brazil 24 Work on reducing systematics is ongoing
Transients with ANTARES Triggered searches (alerts from satellites: Integral, Swift, Fermi) Low backgrounds due to direction and time coincidences Dump all L0 data in 2min window around trigger (i.e. no trigger losses) Special track reconstruction using known direction Neutrino multiplets in time optical follow-up (Tarot in France and at La Silla) Full sky 24h/24 search Sliding time window around events Fast online reconstruction optical follow up to identify source Gravitational waves and neutrinos (Virgo + Ligo + Antares) Drafting a MoU in progress Paulo, Brazil 25
Conclusions An eye is now open on the HE neutrinos coming from the South sky (where the centre of our galaxy is), in complement to Ice Cube looking to the North sky. Both detectors are presently improving their sensitivity limit, until the detection of the first cosmic source of high energy neutrinos? ANTARES made the proof that it was possible to built a deep sea large scale neutrino detector, with an angular resolution better than with the ice. This open the way to a really big detector: KM3NeT Paulo, Brazil 26
KM3NeT A research facility in the Mediterranean Sea A next generation neutrino telescope (at the km-scale) Cabled observatory for Earth and Marine sciences + + + 38 institutes from 10 European countries Paulo, Brazil 27