EURECA  XEUS EURopean-JapanEse micro-Calorimeter Array Piet de Korte

High Energy Astrophysics in the NEXT decade June EURopean-JapanEse Calorimeter Array Project AIMS Design, build, and test of a prototype X-ray Imaging Spectrometer to demonstrate technical feasibility/readiness for a cryogenic space instrument by end 2007 Design, build, and test of a prototype X-ray Imaging Spectrometer to demonstrate technical feasibility/readiness for a cryogenic space instrument by end 2007 Use EURECA as a vehicle to establish a European/Japanese collaboration on micro-calorimeter arrays Use EURECA as a vehicle to establish a European/Japanese collaboration on micro-calorimeter arrays Open up the potential to participate in future missions, like ESA’s XEUS (>2020), NASA’s Con-X (>2020), future Japanese missions like NEXT (2015) and DIOS (2012), Italian’s Estremo (2015), Dutch NEW (2015), etc Open up the potential to participate in future missions, like ESA’s XEUS (>2020), NASA’s Con-X (>2020), future Japanese missions like NEXT (2015) and DIOS (2012), Italian’s Estremo (2015), Dutch NEW (2015), etc Acquire development funding at (multi) national level Acquire development funding at (multi) national level

High Energy Astrophysics in the NEXT decade June EURECA Overview Qualification of a DC-biased pixel in dry ADR at BESSY September 2006 Start Integration 5 x 5 array + FDM-readout Autumn 2006 Initial testing (one channel) Begin 2007 Synchrotron testing (all channels) End 2007

High Energy Astrophysics in the NEXT decade June EURECA ProjectContibutions/Partners ADR Cooler Commercial ADR (Janis)PSI (Zürich) Commercial ADR (Janis)PSI (Zürich) Flight type ADRMSSL (London) Flight type ADRMSSL (London) Detectors  SRON Si-micromaching MESA (UTwente) Si-micromaching MESA (UTwente) Development + tests TMU (Tokyo), INFN(Genua), INAF( Rome), KIP (Heidelberg) Development + tests TMU (Tokyo), INFN(Genua), INAF( Rome), KIP (Heidelberg) Mo-based bilayersIMM(Madrid), ICMA(Barcelona, Zaragossa) Mo-based bilayersIMM(Madrid), ICMA(Barcelona, Zaragossa) LC-filters  SRON Alternative routesINA + ICMA (Zaragossa) Alternative routesINA + ICMA (Zaragossa)SQUIDs Three routesPTB (Berlin), VTT (Helsinki), SII (Japan) Three routesPTB (Berlin), VTT (Helsinki), SII (Japan) Electronics  SRON LNA + FLLVTT (Helsinki), TMU + ISAS (Tokyo) LNA + FLLVTT (Helsinki), TMU + ISAS (Tokyo) AC-BIAS + C&C PSI (Zürich) AC-BIAS + C&C PSI (Zürich) Cold FLLAlcatel Alenia Space (Milano) Cold FLLAlcatel Alenia Space (Milano) Data Acquisition (BESSY)X-ray Astronomy (Leicester) Data Acquisition (BESSY)X-ray Astronomy (Leicester) Data analysis software SystemIFCA(Santander), MSSL(London), SystemIFCA(Santander), MSSL(London), Astr. Obs (Geneva) AlgorithmsX-ray Astronomy (Leicester) AlgorithmsX-ray Astronomy (Leicester)

High Energy Astrophysics in the NEXT decade June 20065EMC/GROUNDING/HARNESS/FILTERING ΔP ≈ 1 fW eq to ΔE ≈ 1 eV Sensors + electronics inside faraday cage Faraday cage consists of: Cryoperm + SC Shield Harness shield (tube) FEE-box integrated on ADR Cable harness EMC electronics rack Single point ground in FEE- box Filters at entrance FEE-box and at 4 K interconnection box Differential electronics and twisted wire-pairs to reject common mode disturbances PC’s + external equipment coupled by optical links

High Energy Astrophysics in the NEXT decade June Cold head shield geometry Cryoperm outer shield 1 4K Superconducting inner shield (Pb or SnPb plated OFHC 500mK OFHC Copper support/thermal link for inner 500mK Cold finger entrance Finger may be electrically coupled with superconductor to inner shield to reduce noise Superconducting harness shield (Pb plated OFHC 4K Radiation entrance window Superconductor shielded loom interconnection & filter 4K (Pb plated OFHC copper) Harness shield, ss304

High Energy Astrophysics in the NEXT decade June 20067FREQUENCY-DOMAIN-MULTIPLEXING CRYOSTAT 1 column or row of pixel- array shown as example FDM operation: - TESs act as AM- modulators - TESs AC-biased at frequencies f1, f2, f3, …. -Each TES equipped with LC band pass filter around carrier frequency to block wide-band noise - Summed signal read-out by one SQUID-amplifier per column

High Energy Astrophysics in the NEXT decade June FDM - Electronics AC-bias generation + Bias Current Cancellation (BCC) by DDS chips Filters consist of superconducting LC-filters at 50 mK DEMUX by ADC + digital processing in FPGA (later ASIC) Signal processing (energy extraction) in FPGA + DSP DDS chips LC- filters FPGA + DSP ADC + FPGA

High Energy Astrophysics in the NEXT decade June Summing TopologyCold Head Layout TES-ARRAY LC-filters SQUIDs Current Summing Bias Comb + capacitive coupling BCC at input Japanese Ch. Flux Summing 8-input SQUID BCC via FB

High Energy Astrophysics in the NEXT decade June Status energy resolution on single pixel NIST (2005) demonstrated for pixels optimized with regard to excess noise In set-up with proper shielding, filtering, and grounding we get reproducibly good energy resolution with as best value: ΔE = 3.4 eV at 5.9 keV; τ =100 μs for pixel with E max ≈ 10 keV 16 hours, analogue filter4 minutes, digital filter

High Energy Astrophysics in the NEXT decade June TES-array – 5x5 bulk-micromachining arrays operational with 5.3 eV keV TiAu Therm. Cu-abs. (stem) Bulk-micromachining Cu/Bi-absorbers No mushroom yet 5.3 eV

High Energy Astrophysics in the NEXT decade June Recent 32 x 32 pixel Array

High Energy Astrophysics in the NEXT decade June TES with Steepness/excess noise control

High Energy Astrophysics in the NEXT decade June NEW ABSORBER – TES COUPLING

High Energy Astrophysics in the NEXT decade June LC-filters - Capacitors based on 20 nm thick Al 2 O 3 -dielectric with - Capacitors based on 20 nm thick Al 2 O 3 -dielectric with C = 4.3 nF/mm2 (expected Q = ) - Inductors on Nb-based washer coils Test-chip with LC-filters for 3,4,6,8 MHz with 100 nH coils Q = 7 MHz R s = 8.7 m Ω Al-bond-wire (4K) and critical current limited (50 μA)

High Energy Astrophysics in the NEXT decade June TES READ-OUT BY SQUID AMPLIFIER SQUID requirements i n < 6 nA/√Hz for L in < few nH Dyn.Range > 10 6 √Hz SQUID response highly a-linear feedback required for linearization and dynamic range improvement (flux-locked-loop/FLL)

High Energy Astrophysics in the NEXT decade June SUPERCONDUCTING SQUID AMPLIFIERS VTT input SQUID Ø N = 0.12 μØ 0 4K L in ≈ 1nH I n = 3.5 pA/√Hz T N = 8 – 12 K (2 nd SQUID- array required) PTB 16-SQUID array Ø N = 0.12 μØ 0 0.3K L in ≈ 3 nH I N = 2.8 pA/√Hz T N = 20 K (LNA just possible) SII 8-input SQUID Ø N = 0.13 μØ 0 4.2K (2nd SII SQUID- array planned)

High Energy Astrophysics in the NEXT decade June Status laboratory confirmation of FDM Tests on TES as detector and mixer: AC-bias experiment at 50 kHz with keV energy resolution AC-bias experiment at 50 kHz with keV energy resolution At 250 kHz 4.8 eV baseline and keV At 250 kHz 4.8 eV baseline and keV AC-bias I-V measurements at 500 kHz to study potential switch-off behavior. For low enough series resistance (LC- filters with high Q) no switch off problems and good relation with DC-curves AC-bias I-V measurements at 500 kHz to study potential switch-off behavior. For low enough series resistance (LC- filters with high Q) no switch off problems and good relation with DC-curves AC-coupling of bias (no shunt resistor) works fine AC-coupling of bias (no shunt resistor) works fine Fully analogue FDM electronics (AC-bias sources, Mixers and de-mixers, FLL-chain, etc) - operational up to 500 kHz - electronic resolution of SQUID, FLL electronics, bias sources and mixers/de-mixers, for detector biased in normal state is 2 eV keV New measurements going on in fully digital de-mux system and well shielded cryostat to prove that ΔE DC = ΔE AC

High Energy Astrophysics in the NEXT decade June AC-bias card AC-bias fed per column 8 DDS-chips power 8 pixels 8 DDS-chips give BCC for 8 pixels AC-bias DDS chips BCC DDS chips Backplane interfaceACTEL FPGAHK Baseband filter, amplifier RS485

High Energy Astrophysics in the NEXT decade June Summary and Conclusions EURECA well under way with Preliminary Design Review in Jan Start integration 1 st channel in ADR by end-2006 EURECA well under way with Preliminary Design Review in Jan Start integration 1 st channel in ADR by end-2006 Integration of single TES-pixel with DC-electronics in dry ADR started with aim to perform BESSY-calibrations in 2 nd week of September 2006 Integration of single TES-pixel with DC-electronics in dry ADR started with aim to perform BESSY-calibrations in 2 nd week of September x 5 detector-arrays available with ΔE = keV. 32 x 32 arrays available as well 5 x 5 detector-arrays available with ΔE = keV. 32 x 32 arrays available as well FDM with standard FLL-electronics will only multiplex about 10 pixels per SQUID-channel with XEUS requirements (E max =10 keV, ΔE = 2 eV, and τ = 100 μs) (30 with Con-X requirement) FDM with standard FLL-electronics will only multiplex about 10 pixels per SQUID-channel with XEUS requirements (E max =10 keV, ΔE = 2 eV, and τ = 100 μs) (30 with Con-X requirement) Coarse/Fine amplifier topology, Base-band feedback, or a combinations should offer appreciably better performance. (about 4 x more pixels). It is planned to start working on this by 2007 in parallel to mainstream EURECA Coarse/Fine amplifier topology, Base-band feedback, or a combinations should offer appreciably better performance. (about 4 x more pixels). It is planned to start working on this by 2007 in parallel to mainstream EURECA SQUIDs close to the requirements are available. But further optimization is still required/possible SQUIDs close to the requirements are available. But further optimization is still required/possible ASIC developments for Space (power reduction) is starting ASIC developments for Space (power reduction) is starting

High Energy Astrophysics in the NEXT decade June Coarse/Fine Amplifier Topology (Feed-forward) Fine amplifier measures noise, non- linearity of coarse amplifier + system offsets Factor 10 increase in Dyn. Range requires < 10% channel tuning. For 8 ns delay (ampl. + cable) this limits system to 2 MHz Cold feed-forward enables 10 MHz bandwidth (control gain of both channels!) Will be studied in parallel with EURECA for XEUS