ANTARES Status report Experiment overview Status of construction Status of operation Status of physics analyses Presentation at ICATPP07. Oct 8, Como, Italy Dmitry Zaborov (ITEP, Moscow, Russia) on behalf of the ANTARES collaboration Oct 8, 2007D. Zaborov. ANTARES status report2 23 Institutes from 7 European countries 40 km submarine cable -2475m ANTARES shore station Collaboration & experiment location Oct 8, 2007D. Zaborov. ANTARES status report3 Detection principle 43 Sea floor p 10 4 atm p, 10 7 atm Reconstruction of trajectory (~ ) from timing and position of PMT hits interaction Cherenkov light from 3D PMT array cosm Oct 8, 2007D. Zaborov. ANTARES status report4 Detector layout ~70 m 12 lines (900 PMTs) 25 storeys / line 3 PMTs/storey 350 m 100 m 14.5 m Junction box Readout cables 40 km to shore Horizontal layout Sea bed ~ m a storey Oct 8, 2007D. Zaborov. ANTARES status report5 A few remarks on detector performance Sensitivity to - and - (via -> decay) neutrino using muon tracks High angular resolution (0.3 at 10 TeV) Effective area close to 0.1 km 2 in TeV range (with 12 Lines) Sensitivity to all neutrino types using showers High energy resolution (~25%) Significant sensitivity in sub-TeV range search for dark matter (neutralino) neutrino oscillations point-like sources Sky coverage complementary to AMANDA/IceCube Looking through the Earth Mostly Southern sky is visible Field of view follows Earth rotation Most of our Galaxy within field of view (Galactic center, intermediate-mass black holes, ) Oct 8, 2007D. Zaborov. ANTARES status report6 Basic detection and calibration elements Hydrophone: acoustic positioning Optical Module: 10 PMT in 17 glass sphere photon detection Local Control Module (in Ti container): Front-end ASIC, Clock, DAQ/SC, compass/roll/pitch Optical Beacon with blue LEDs: timing calibration Oct 8, 2007D. Zaborov. ANTARES status report7 Detector Line deployment Oct 8, 2007D. Zaborov. ANTARES status report8 Submarine cable connection Oct 8, 2007D. Zaborov. ANTARES status report9 Current status L11 L9 L10 L12 L7 L8 L6 L4 L2 L3 L5 L1 IL07 seismometer 100 m N Junction box Submarine cable to shore 4250 N 610E 5 detector lines operational (since January 29 th ) (Oct. 2007) 4 lines + instrumentation line are awaiting connection 3 lines to be deployed Oct 8, 2007D. Zaborov. ANTARES status report10 Construction schedule Linedeploymentconnection IL 07Done (18/07/07) Dec 07 Line 6Done (15/03/07) Dec 07 Line 7Done (04/04/07) Dec 07 Line 8Done (07/07/07) Dec 07 Line 9Done (26/07/07) Dec 07 (Jan 08) Line 10Nov 07Dec 07 (Jan 08) Line 11Mar 08 Line 12Mar 08 * Source: ANTARES schedule v070910, ANTARES-L, collaboration meetings Oct 8, 2007D. Zaborov. ANTARES status report11 Instrumentation Line IL07 New six-storey instrumentation line (MILOM had 3 storeys) Includes modified MILOM instruments: 2 ADCPs (Acoustic Doppler Current Profilers), shooting up & down 2 CT (Conductivity-Temperature) probes with water pump 2 CSTAR devices with improved sensitivity & horizontal mechanical mounting (measure optical properties of the water) Sound Velocimeter Seismometer with direct Ethernet link Includes several new instruments: 2 Sensitive cameras + IR flash looking at an Optical Module O 2 probe Includes 3 acoustic detection storeys equipped with 6 hydrophones each SV O2O2 Oct 8, 2007D. Zaborov. ANTARES status report12 In situ calibration with Potassium-40 (recently invented) 40 K 40 Ca e - ( decay) Cherenkov Coincidence plot Peak offset Rate of correlated coincidences High precision (~5%) monitoring of OM efficiencies LED Beacon calibration confirmed 13.4 Hz MC prediction 13+/-4 Hz Mean 0 RMS 0.7 ns *no charge calibration used No dependence on bioluminescent activity has been observed - this confirms the single photon character of bioluminescent emission Oct 8, 2007D. Zaborov. ANTARES status report13 Data collected with 5 Lines (Oct 1, 2007) Active time 190 days # muon triggers Average baseline rate 65 kHz # muon triggers: burst fraction < 20% Data taking efficiency (time not spent on calibration, between runs, etc) in Apr Aug > 85 % # neutrinos> 150 * Line 3 is connected since Jan 27, Lines 4 & 5 since Jan 29, 2007 Physics data taking with 5 Lines started the same day Oct 8, 2007D. Zaborov. ANTARES status report14 An example of muon bundle event Downgoing muon seen with one Line height hit time Oct 8, 2007D. Zaborov. ANTARES status report15 A neutrino candidate event (5 lines) =35 o Oct 8, 2007D. Zaborov. ANTARES status report16 First results Neutrino candidates Atmospheric muons downgoing upgoing Subset of Line 1-5 data (4.3 M events) Quality cut for upgoing tracks No alignment used Reconstructed nadir angle (very preliminary) Oct 8, 2007D. Zaborov. ANTARES status report17 Ongoing analyses Muon flux is being measured (and compared to Monte Carlo calculations): Using trigger rate Need precise knowledge of absolute OM efficiency and background-induced trigger rate Number of reconstructed tracks Need high level of control over systematic uncertainties of the reconstruction algorithms (NEW) coincidence correlation analysis Use correlated coincidences in adjacent detector storeys (typical signature of physics events) Access to low energy muon flux, depth dependence(!), angular information (fraction of vertical muons) Smaller dependence on OM efficiencies Angular distribution is under study Different reconstruction approaches are being tried Oct 8, 2007D. Zaborov. ANTARES status report18 Ongoing analyses (continued) Atmospheric neutrino flux Relies on thorough understanding of reconstruction efficiency Neutrino sky mapping & search for point-like sources Ongoing, see presentation by Fransisco Salesa Setting limits on diffuse flux Using showers GRB neutrino Analyzing data for 100 GRB alerts Galactic center trigger First directional trigger in ANTARES (operating since July) Dark matter Neutralino annihilation in the Sun - start looking for Other sources - relies on point source search Exotics Monopoles, nuclearites and more Oct 8, 2007D. Zaborov. ANTARES status report19 Outlook Five detector lines are operating in the sea the largest neutrino detector in the Northern hemisphere. Four more lines + new instrumentation line have been deployed and are awaiting connection. The last three are prepared. Data taking is ongoing with nearly nominal efficiency. Background conditions are affordable. Data sample is growing by 10 6 muon triggers every week. The concept and the design of the experiment are proved. Detector calibration can be performed with the required precision. Upward-going neutrinos can be separated from atmospheric muons. Physics analysis is advancing. Atmospheric muons and neutrinos are measured. The experiment is already fully functional and keeps delivering data. Need to finish construction and accumulate more data. Oct 8, 2007D. Zaborov. ANTARES status report20 Spare slides Oct 8, 2007D. Zaborov. ANTARES status report21 Sea features vs. detector features Optical background from 40 K decays and bioluminescence Stable component 40 kHz Variable component Bursts Optical modules organized in triples for easier triggering and track finding (the hardest part of reconstruction) XOn/XOff mechanism Prevent sending burst data to shore Smart triggers (optional) Use time relations between floors Small light scattering Forward-peaked scattering Small spread in hit arrival time (good time residuals) High timing precision ( 1 ns) Limited by transit time spread of PMTs, dispersion of light velocity, and calibration accuracy Provides high angular resolution to the telescope Floating geometry Monitor actual positions of detector elements Acoustic positioning, tiltmeters, compasses Oct 8, 2007D. Zaborov. ANTARES status report22 Data acquisition, Clock & Trigger All-data-to-shore DAQ High bandwidth fiber-optic network (1 GBit /sec/ Line, DWDM) Designed to withstand heavy bioluminescence Fiber-optic clock system Synchronize electronics modules with precise GPS clock on shore Deliver commands Onshore trigger Pure software Runs on dedicated PC farm Allows for highly efficient customized triggers Many triggers can be run in parallel (just need CPU power) GRB trigger Start on satellite GRB alert Save all data within sufficiently long snapshot (cache in memory) Analyze offline Directional triggers Galactic center Sun Any other potential source