210 likes | 227 Views
ryogenic are vent earch with uperconducting hermometers. C R E S S T. Present and Future Cryogenic Dark Matter Search in Europe. EURECA. EURECA. Wolfgang Rau, Technische Universität München. CRESST Max-Planck-Institut for physics (Munich) Technical University Munich
E N D
ryogenic are vent earch with uperconducting hermometers C R E S S T Present and Future Cryogenic Dark Matter Search inEurope EURECA EURECA Wolfgang Rau, Technische Universität München
CRESST • Max-Planck-Institut for physics (Munich) • Technical University Munich • University of Oxford • Laboratori Nazionali del Gran Sasso • University of Tübingen • University of Warwick • EDELWEISS • CEA-Saclay DAPNIA/DRECAM • CRTBT Grenoble • CSNSM Orsay • FZK/Univ. Karlsruhe • IAP Paris • IPN Lyon • Laboratoire Souterrain de Modane EURECA + CERN + MPIK (Heidelberg) + ... Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
ILIASIntegrated Large Infrastructures for Astroparticle Science • Financed by EU • Infrastructure for astroparticle physics in Europe (not complete, but a good start) • Contains different structures: • Networks (Dark Matter, Double Beta, Underground Science, Gravitational Waves, Theory) • Joint Research Activities (Double Beta, LowBackground, Gravitational Waves) • Transnational Access (Underground laboratories) • 12 Countries, 20 Contractors / ~140 Institutes, > 1000 scientists • Forum for discussion of future plans in Europe Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
Overview • EDELWEISS • Technique • Status • Next Future • CRESST • Technique • Status • Next Future • EURECA • Idea • Plans • Status Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
W-TES: (Tc = 6-10 mK) W 68 mm² Au heater Al contact Heater for stabilization (DC) and calibration (test pulses) CRESST – Technique • Target: CaWO4 • Cylindrical, /h: 4 cm • Mass: 300 g • Light output: ~ 1 % (g’s) • Light detector • 30 30 0.4 mm Si • Thresholds • Phonons: 2 keV • Light: 20 eV • ~2 keVee • Discrimination: 12 keV Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
Light energy Reflector CaWO4 Recoil energy CRESST – Technique Quenching • Nuclear recoil less light than electron recoil! • Different light yield for different nuclei (O, Ca, W)? • Two experiments to measure Quenching (so far room temp.): • Neutron scattering • Ion beam • Both indicate: less light for heavy nuclei Additional support from data -band -band • a-band between g- and n-band • recoiling nuclei from a-decay (O) n-band W-band Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
Gran Sasso 3600 m w.e. CRESST – Technique Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
Run 28, Daisy Run 28, Julia (bad light resolution) Light yield Light yield Energy in Phonon Channel [keV] Energy in Phonon Channel [keV] CRESST – Status Spring 2004: 2 months run with 2 detectors sensitivity limited by neutrons if high QF applies for WIMP recoils: results comparable to EDELWEISS (10-6 pb) Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
66 SQUIDs on He-flange CRESST – Status Shielded cryostat Since April 2004: upgrade • Install neutron moderator (30-50 cm PE, 11 t); µ-veto • Increase number of readout channels (4 66) • Enlarge target mass (600 g 10 kg) PE neutron moderator Plastic scintill. m-veto Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
CRESST – Next Future • Finish major work by beginning of 2005 • Restart with few detectors • Install new detector holder late spring • Increase target mass to 10 kg within 2005 • Situation in Gran Sasso not clear (major construction work expected – influence on CRESST so far unknown) Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
Ionization: Inner disk / outer ring (“guard”) with a-Si / a-Ge EDELWEISS - Technique Target: cyl. Germanium crystal, 320 g 7.0 cm, height 20 mm (beveled) Thermal: NTD (~ 20 mK) Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EDELWEISS - Technique Thresholds Heat: 0.4 – 2 keV Ionization: 1.1 – 1.5 keV Analysis Ion. trigger: 20 – 30 keV Phon. trig.: 15 keV Resolution Heat: 0.6 – 2 keV @ 10 keV 2 – 4 keV @ 122 keV Ion.: 2 – 3 keV @ 122 keV Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EDELWEISS - Status 2003 Data (3 new detectors) • Ion. trigger • 20 kg d • Thr: • 20/30 keV • 3 events • Phonon trigger • 22 kg d • Thr: • 15 keV • 18 events • 1 coinc. (n-n) 2000 – 2003: 62 kg d, 40 events (only 3 for 30–100 keV) Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EDELWEISS - Status NbSi sensors for athermal phonons NbSi meander Outer electrode • NbSi: metal-isolator transition (high R) • 2 surfaces covered (ionization + heat sensors) • Two-component signal: • Thermal (energy) • Athermal (surface discrimination) • Successful test with 200 g modules in EW I: • 90 % rejection • 50 % efficiency Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EDELWEISS – Next Future Edelweiss II @ Modane (4800 m w.e.) • Aim for sensitivity improvement 100 • Installation started 04/04 – expected to finish summer 05 • 1st phase: 21 NTD detectors (320 g), 7 NbSi detectors (400 g) Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
Improved shielding • 20 cm lead • 50 cm PE • Muon veto EDELWEISS – Next Future • Large new cryostat • low activity • inverse geometry • up to 120 detectors Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EURECA uropean nderground are vent search with alorimeter rray E U R E C A Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EURECA – Idea • Next generation DM search to explore most of SUSY parameter space • Cryogenic experiments very promising • Target mass in the 1 ton range • Different targets (WIMP signature) • Collect European competence Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EURECA – Plans • Discriminating cryogenic detector to reach a sensitivity 10-10 pb for coherent interaction • Better sensitivity for spin-dependent interaction • Design study to investigate requirements and technical challenges: • Detector development (larger modules, better discrimination, other targets) • Optimal shielding strategies • Background reduction (handling/cleaning) and modeling (Monte Carlo simulations) • Cryogenics, electronics, cabling, DAQ Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
ILIAS ILIAS EURECA – Plans Structured in Working groups: • Detector Development • Low Radioactivity • Neutron Background, µ-veto and Shielding • Cryogenics • Cabling • DAQ • Underground site issues Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04
EURECA – Status • Letter of Intent to ApPEC summer 2004 • Start proposal process September 2004 • Present Proposal to ApPEC January 2005 • Present Proposal to Funding Agencies • Start work 2005/06 ??? Wolfgang Rau, TUM Future Direct Detection, Chicago 12/04