N I K A Grenoble (Néel, IRAM, LPSC, LAOG) Cardiff SRON Roma-Trento Néel IRAM KIDs Array Grenoble (Néel, IRAM, LPSC, LAOG) Cardiff SRON Roma-Trento

NIKA timeline November 2008 : November 2008 :Kick-off 2009 : 2009 : First antenna-doupled arrays in February First demonstration of LEKIDs arrays in May Final arrays made in September pixels, mono-band 2mm, run in October Pico Veleta Sensitivity: 1.2· W/Hz 0.5 Reference: 2010 : 2010 : 112 x 2 pixels Sensitivity (in progress) 3  6· W/Hz 0.5 Sensitive to only one polarisation ! Dual-band: 125  170GHz et 180  270GHz 2011 (GOALS) : 2011 (GOALS) :to be discussed (many options)

Electronics PAST / PRESENT NIKA 2009 NIKA 2009: Bonn electronics 400MHz (ADC 8 bits), FFT, max. rate 5Hz NIKA 2009 NIKA 2009: Néel box (« Loren ») 50MHz (ADC 12 bits), 32 ch., max. rate 50 Hz NIKA 2010 NIKA 2010: ROACH board (Néel box with up-down converter and USB attenuators) 230MHz (ADC 12 bits), 112 channels, rate 22 HzFUTURE LPSC 2011 LPSC 2011GOAL : > 256 channels modules over > 400MHz band Fast rate (at least 20Hz are needed) First prototype funded by CNES and IN2P3 SRON 2011 SRON 2011 see Andrey, but GOAL is >1GHz band, FFT (rate ?)

Noise spectrum on (good) sky Average LEKIDs detectors noise : 2Hz / Hz 0.5 at 1Hz (stable during the run

Misterious 50s-period noise Appearing from time to time, lasting for a few hours and then disappearing. 100Hz steps !!! Detectots noise is less than 10Hz p-p !!

50s noise again

A HUGE insect in the cabin

EMIR chopper ON/OFF

B-field jumps on antenna-coupled array

B-field jumps on LEKIDs

Laboratory (sky-simulator) performances Problem confirmed on the telescope. Can be explained by the electronics : sensitivity depends critically on power per KID. Taken into account for LPSC2011 electronics. Best pixel < 2 mK/Hz 0.5 (  1.1 mK/Hz 0.5 if « speed read-out ») Average 4mK/Hz 0.5   4· W/Hz 0.5 per pixel

Very rough estimation of S/N Please take it as very raw. Then other effects might limit the noise on real maps. The average « very raw » S/N on Mars is: 2mm1.25mm Signal : Signal : 2-4 kHz 10 kHz Noise : Noise : 2 Hz/Hz Hz/Hz 0.5 Mars flux : Mars flux : 40Jy107Jy S/N S/N  Hz 0.5  Hz 0.5 Sensitivity (1Hz) Sensitivity (1Hz)  20-40mJy/Hz 0.5  mJy/Hz 0.5 (per pixel) NEP (1Hz)  estimated by sky simulator !! IN ANY CASE IT’S MORE OR LESS WHAT WE EXPECTED BASED ON THE SKY SIMULATOR RESULTS.

Exemple résultat : CygA

Exemple résultat : DR21(OH)

Spectral response (Grenoble MPI, 11/2010)

Conclusions DETECTORS DETECTORSClearly better than 2009 at 2mm. A factor of 4 very raw S/N estimation. Still to be confirmed on real maps (B fields ??). Best LEKIDs pixels tested on sky simulator already almost OK. Average performances of the array to be improved: - dual-polarisation meanders (LEKIDs). Better for cross-talk too. - AR coating (LEKIDs and antennas) - electronics (same power on all pixels) - read-out on « maximum speed » (but less dynamics) - if all that not enough: TiN (or similar) for higher response - …. Andrey ? Jochem ? PIXELS COUNT PIXELS COUNTMuch better than in 2009 (factor 4-6). Limited by the electronics. Arrays sizes will now grow according to electronics developments. OPTICS OPTICSSame cryostat/filters is OK up to 3arc-min field-of-view. Use a real dichroic for splitting (factor of  2 in power).

Plans for 2011 A FURTHER TECHNICAL RUN ? TWO SEPARATE RUNS ? A MORE « USABLE » INSTRUMENT ? WORKING ON THE BIG CAMERA ? HOW BIG ? IN CASE WE GO FOR SPRING 2011 : CRYOSTAT  PULSE-TUBE (if possible) PIXELS  224 per array, over a 400MHz band ELECTRONICS  Baseline: LPSC2011. ROACH is backup if LPSC is still under development. FILTERS  from NIKA2010 SPLITTER  DICHROIC (if possible) DETECTORS 2mm  Same as NIKA2010; dual-polar if dichroic DETECTORS 1mm  Antennas or LEKIDs (the best, taking into account the number of pixels that can be actually read-out by existing electronics at that time, and sensitivity)