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NIKA (Néel IRAM KID Array) First light at the 30-m IRAM dish. NIKA collaboration: Institut Néel - Grenoble AIG - Cardiff SRON - Utrecht and Groningen Max Planck Institute - Bonn IRAM - Grenoble - La Sapienza – Roma + IRST - Trento - LPSC - Grenoble. T base = 60mK.
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NIKA (Néel IRAM KID Array) First light at the 30-m IRAM dish • NIKA collaboration: • Institut Néel - Grenoble • AIG - Cardiff • SRON - Utrecht and Groningen • Max Planck Institute - Bonn • IRAM - Grenoble • - La Sapienza – Roma + IRST - Trento • - LPSC - Grenoble A. Monfardini, IAP 30/07/2010
T base = 60mK Horizontal Dilution Cryostat Designed and fabricated in Grenoble A. Monfardini, IAP 30/07/2010
NIKA installed – 19/10/2009 To IRAMsecondary mirror … through this hole NIKA interface optics Cryostat (on anti-vibration table) Credit: L. Swenson A. Monfardini, IAP 30/07/2010
Designed and fabricated in Grenoble (Néel and PTA). NIKA: 30 pixels LEKIDs array Operating at 130-170GHz • Data-sheet: • - 40nm Al • - fR = 1.50 - 1.55 GHz • - Qc 30,000 • 3dB deep resonances • (large scatter) • Read-out : Grenoble • FPGA electronics Polarisation sensitive Average optical NEP (1Hz) on telescope : 10-15 W/Hz0.5 Real conditions, UNDER > 10pW/pixel loading. ... actually better considering that we only have 1 polarisation A. Monfardini, IAP 30/07/2010
NIKA 2009: Mars transits (raw data) A. Monfardini, IAP 30/07/2010
BL1418+546 (1.2 Jy) Visible already in the first scan, also on single pixels maps. Good S/N A. Monfardini, IAP 30/07/2010
Extended sources : M87 Credit: F.X. Desert More details on the NIKA run : arxiv/1004.2209 (A&A, in press) A. Monfardini, IAP 30/07/2010
SKY noise ( f-2.1) Detectors noise ( f-0.55) Noise Spectrum (on-sky, during observations) Sky noise (correlated) dominates below 0.4 Hz (average sky conditions) Part of detectors noise is correlated (common mode gain variations) A. Monfardini, IAP 30/07/2010
NIKA 2010: larger and more sensitive • Reduced the phase noise by • playing with the design • Improved the optical response • by reducing the film thickness • Improved lithography quality • and made larger arrays • Optics is OK in lab • (well separated beams) • EM cross-talk shuffling the • resonances. Work in progress. IN OUT Best pixels in 2010 (June). Optical NEP (1 Hz) 2·10-16 W/Hz0.5 Best array so far (last week). Average optical NEP 6·10-16 W/Hz0.5 A. Monfardini, IAP 30/07/2010
Bands : 1.25 – 2.05 mm Pixels : 144 x 2 F/1.9 Field-of-view : 1.5 arc-min It’s READY ! First complete test (Sky Simulator) next week with : - Néel: mechanics, cryostat, lenses (HDPE) - Cardiff: (filters, optical splitter) - 2mm (IRAM/Néel) and 1.25mm (Roma/Trento) arrays NIKA 2010: dual-band too Pre-scheduled for the end of October on the 30-m telescope. A. Monfardini, IAP 30/07/2010
Cosmics: first « fast MUX » measurement We could triangulate the interaction position (300m error for 2.2mm pixels). X-rays 6 keV photons interacting in the substrate are seen clearly (S/N >> 10). A REAL PROBLEM FOR SPACE/SENSITIVE APPLICATIONS For more details : L.J. Swenson et al., APPLIED PHYSICS LETTERS 96, 263511 (2010) A. Monfardini, IAP 30/07/2010
Status : - Demonstrated in lab up to 160 pixels multiplexed on a single line (Grenoble setup and Bonn MPI electronics). Electronics constantly in progress. - Best pixels exhibit NEP 2·10-16 W/Hz0.5under 10pW loading per pixel Sensitivity improvements for Bpol : - Reducing the background translates directly in NEP reduction - New materials (e.g. very promising TiN, see arxiv/1003.5584) - Horns or not horns ? So far filled arrays ... Horns to be studied in case. - Challenging but not impossible (requires a coherent R&D FR-UK-IT) Cosmics (a real issue !) : - KIDs are Sensitive to a-thermal (Cooper pair breaking) substrate phonons - Not sensitive to thermal phonons ≠ bolometers - Rate on 2mm pixels (and > 10-16 W sensitivity) > 0.1Hz at sea level ! - Faster than bolometers (...but not enough). High Q, long qp slow resonator - BIG questions are now: - a-thermal phonons mean free path in thin membranes ??? - solid membrane OK (easy) or need spider-like structures (more difficult) ?? Electronics : - Not a huge problem I think for up to 1000 pixels. Medium term goal is a MUX factor of 103. ADCs improvements might allow 104 in long term. Conclusions in view of BPol A. Monfardini, IAP 30/07/2010
THANKS A. Monfardini, IAP 30/07/2010
BONN (Max Planck Institut) FFTS (2009) – not available for NIKA 2010 Useful Bandwidth: 400 MHz Max. readout rate: 5 Hz FFT points: up to 32k Tones spacing: down to 12.2 kHz Max number of channels tested: 160 Grenoble (LPSC and Néel) FPGA READOUT(2010) Useful Bandwidth: 125 MHz Max. readout rate: 2 MHz Max. number of channels 128 Tones spacing: down to 1Hz OPEN SOURCE READOUT(2010) Useful Bandwidth: 250 MHz Max. readout rate: > 2 MHz Max. number of channels for now up to 96 Tones spacing: down to 1Hz Collaboration : UCSB, Berkeley, Caltech-JPL, NIST, Goddard, Grenoble, UK Existing MUX Read-Outs A. Monfardini, IAP 30/07/2010
Tool to find resonances - BEFORE A. Monfardini, IAP 30/07/2010
Tool to find resonances - AFTER A. Monfardini, IAP 30/07/2010