Status of the KM3NeT Project. Oleg Kalekin Astroparticle Physics Workshop Baikal, Ulan-Ude Maksimiha

Transcription

1 Status of the KM3NeT Project Oleg Kalekin Astroparticle Physics Workshop Baikal, Ulan-Ude Maksimiha

2 The Neutrino Telescope World Map ANTARES, NEMO, NESTOR joined efforts to prepare a several km 3 -size neutrino telescope in the Mediterranean NEMO Sea KM3NeT ( O. Kalekin: KM3NeT Status, Baikal workshop,

3 The Objectives Central physics goals: Investigate neutrino point sources in energy regime TeV Complement IceCube field of view Exceed IceCube sensitivity Implementation requirements: Construction time 5 years Operation over at least 10 years without major maintenance O. Kalekin: KM3NeT Status, Baikal workshop,

4 Particle Propagation in the Universe protons E>10 19 ev (100 Mpc) Cosmic accelerator neutrinos gammas ( Mpc) protons E<10 19 ev 1 parsec (pc) = 3.26 light years (ly) O. Kalekin: KM3NeT Status, Baikal workshop,

5 How Do Neutrino Telescopes Work? Upward-going neutrinos interact in rock or sea/lake water. Emerging charged particles (in particular muons) produce Cherenkov light in water. Detection by array of photomultipliers. γ c θ c ν μ 0.7є E (TeV) 0. 6 O. Kalekin: KM3NeT Status, Baikal workshop,

6 Background Cosmic Down going atmospheric muons Up going atmospheric neutrinos p Local 40 K Bioluminescence p atm O. Kalekin: KM3NeT Status, Baikal workshop,

7 Technical Design Objective: Support 3D-array of photodetectors and connect them to shore (data, power, slow control) Optical Modules Front-end electronics & readout Readout, data acquisition, data transport Mechanical structures, backbone cable General deployment strategy Sea-bed network: cables, junction boxes Calibration devices Shore infrastructure Assembly, transport, logistics Risk analysis and quality control Design rationale: Cost-effective Reliable Producible Easy to deploy O. Kalekin: KM3NeT Status, Baikal workshop,

8 The KM3NeT Research Infrastructure (DU) O. Kalekin: KM3NeT Status, Baikal workshop,

9 Detector Building Blocks A few separated building blocks to permit an operation simultaneously with further maintenance Irregularities of DU positions for smooth angular sensitivity O. Kalekin: KM3NeT Status, Baikal workshop,

10 Seafloor network Two concepts: Primary junction box in the center of the detector Distributed primary junction boxes in a ring structure O. Kalekin: KM3NeT Status, Baikal workshop,

11 DUs: Bars, Strings, Triangles Technical design report: Flexible towers with horizontal bars Simulation indicates that local 3D arrangement of OMs increases sensitivity significantly Single- or multi-pmt OMs Slender strings with multi-pmt OMs Reduced cost per DU, similar sensitivity per Euro Strings with triangular arrangements of PMTs Evolution of ANTARES concept Single- or multi-pmt OMs Conservative fall-back solution O. Kalekin: KM3NeT Status, Baikal workshop,

12 The Slander String 20 mpmt DOMs supported by two parallel ropes Power and data cables separated from ropes; single backbone cable with breakouts to storeys Storey length = 6m Distances between DOMs = 40 m The lowest DOM at 120 m above the seabed The total height of the DU ~870 m O. Kalekin: KM3NeT Status, Baikal workshop,

13 The Flexible Tower with Horizontal Bars 20 storeys Each storey supports 6 spmt OMs in groups of 2 or 2 mpmt OMs Storeys interlinked by tensioning ropes, subsequent storeys orthogonal to each other Power and data cables separated from ropes; single backbone cable with breakouts to storeys Storey length = 6m Distance between storeys = 40 m Distance between DU base and first storey = 100m O. Kalekin: KM3NeT Status, Baikal workshop,

14 Deployment strategy Compact package Deployment Self-unfurling O. Kalekin: KM3NeT Status, Baikal workshop,

15 Deployment O. Kalekin: KM3NeT Status, Baikal workshop,

16 Slander String Deployment O. Kalekin: KM3NeT Status, Baikal workshop,

17 Deployment: surface and bottom Delta Berenike platform Cougar remotely operated Vehicle (ROV) O. Kalekin: KM3NeT Status, Baikal workshop,

18 DOMs: single-pmt, multi-pmt TDR: spmt classical : 8-inch PMT with increased quantum efficiency (instead of 10 inch) 13-inch glass sphere (instead of 17 inch); no valve (requires vacuum assembly); no mu-metal shielding mpmt: 31 3-inch PMTs in 17-inch glass sphere Single photon counting improvement Directional sensitivity Reduction of mechanical structure O. Kalekin: KM3NeT Status, Baikal workshop,

19 mpmt DOM A B 31 3-inch PMTs in 17-inch glass sphere (cathode area~ 3x10 PMTs) 19 in lower, 12 in upper hemisphere D C C X Suspended by compressible foam core PMT 31 PMT bases (total ~140 mw) (D) Front-end electronics (B,C) Al cooling shield and stem (A) Single penetrator 2mm optical gel (ANTARES-type) O. Kalekin: KM3NeT Status, Baikal workshop,

20 mpmt DOM X O. Kalekin: KM3NeT Status, Baikal workshop,

21 Three-inch+ PMTs ET Enterprises: 100 new D783FKLA PMTs delivered Larger diameter PMT under development X Hamamatsu: 50 modified R6233mod PMTs delivered 3 new 80mm diameter R12199 PMTs delivered, 200 odered (delivery July-December 2012) MELZ (Moscow): a few new 82mm diameter will be delivered soon New Chinese PMT manufacturer: delivery of a few PMTs in December 2012 utilizing Photonis expertise O. Kalekin: KM3NeT Status, Baikal workshop,

22 Reflectors Increase of the photon detection efficiency by ~30% X Aluminum ring for PMTs with lens like input window Glass lens with a reflective layer on its side for hemispherical PMTs O. Kalekin: KM3NeT Status, Baikal workshop,

23 Amplitude Front-End Electronics: Time-over-Threshold From the analogue signal to time stamped digital data: t 1 t 2 t 3 t 4 t 5 t 6 Time Threshold 1 Threshold 2 Threshold 3 Analogue signal Front End ASIC Digital data System on Chip (SoC) Ethernet TCP/IP data link Shore Scott chip FPGA+processor O. Kalekin: KM3NeT Status, Baikal workshop,

24 Same Readout for Single- and Multi-PMT OMs N thresholds for 1 PMT Mem 1 Mem 2 FIFO + ZS SoC Scott N/k thresholds for k PMTs Mem 1 Mem 2 FIFO + SZ SoC Scott O. Kalekin: KM3NeT Status, Baikal workshop,

25 Data Network All data to shore: Full information on each hit satisfying local condition (threshold) sent to shore Overall data rate ~ 25 Gbyte/s Data transport: Optical point-to-point connection shore-om Optical network using DWDM and multiplexing Served by lasers on shore Allows also for time calibration of transmission delays Deep-sea components: Fibres, modulators, mux/demux, optical amplifiers (all standard and passive) O. Kalekin: KM3NeT Status, Baikal workshop,

26 Data Network JB junction box MM master module REAM reflective electro absorption modulator S1, S2 switches DWDM dense wavelength division multiplexing O. Kalekin: KM3NeT Status, Baikal workshop,

27 Next Steps and Timeline Next steps: Prototyping and site selection Timeline: O. Kalekin: KM3NeT Status, Baikal workshop,

28 Budget for prototyping 40 million Euro available from France, Italy, The Netherlands, and Romania. Italian groups proceed first with the backup solution Towers with bars and large PMTs then join the main line Slander Strings with mpmt DOMs O. Kalekin: KM3NeT Status, Baikal workshop,

29 Candidate Sites Locations of the three pilot projects: ANTARES: Toulon NEMO: Capo Passero NESTOR: Pylos Long-term site characterisation measurements performed Site decision requires scientific, technological and political input O. Kalekin: KM3NeT Status, Baikal workshop,

30 Thank you O. Kalekin: KM3NeT Status, Baikal workshop,

31 Backup slides O. Kalekin: KM3NeT Status, Baikal workshop,

32 Detector Building Blocks Bars: 127 DUs, distance 180/150 m 2 km O. Kalekin: KM3NeT Status, Baikal workshop,

33 Angular resolution O. Kalekin: KM3NeT Status, Baikal workshop,

34 Diffuse flux sensitivity O. Kalekin: KM3NeT Status, Baikal workshop,

35 Sensitivity to point sources O. Kalekin: KM3NeT Status, Baikal workshop,