NNéelIIRAMKKIDsAArray

Grenoble (Néel, IRAM, LPSC, LAOG)Grenoble (Néel, IRAM, LPSC, LAOG)

CardiffCardiff

SRONSRON

Roma-TrentoRoma-Trento

NIKA timeline November 2008 :November 2008 :Kick-off

2009 :2009 : First antenna-doupled arrays in FebruaryFirst demonstration of LEKIDs arrays in MayFinal arrays made in September30-40 pixels, mono-band 2mm, run in October Pico VeletaSensitivity: 1.2·10-15 W/Hz0.5

Reference:

2010 :2010 : 112 x 2 pixelsSensitivity (in progress) 36·10-16 W/Hz0.5

Sensitive to only one polarisation !Dual-band: 125 170GHz et 180 270GHz

2011 (GOALS) :2011 (GOALS) : to be discussed (many options)

ElectronicsPAST / PRESENTPAST / PRESENTNIKA 2009NIKA 2009: Bonn electronics 400MHz (ADC 8 bits), FFT, max. rate 5Hz

NIKA 2009NIKA 2009: Néel box (« Loren ») 50MHz (ADC 12 bits), 32 ch., max. rate 50 Hz

NIKA 2010NIKA 2010: ROACH board (Néel box with up-down converter and USB attenuators) 230MHz (ADC 12 bits), 112 channels, rate 22 Hz

FUTUREFUTURELPSC 2011LPSC 2011 GOAL : > 256 channels modules over > 400MHz band

Fast rate (at least 20Hz are needed) First prototype funded by CNES and IN2P3

SRON 2011SRON 2011 see Andrey, but GOAL is >1GHz band, FFT (rate ?)

Noise spectrum on (good) sky

Average LEKIDs detectors noise : 2Hz / Hz0.5 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 !!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 : sensitivitydepends critically on power per KID. Taken into account for LPSC2011 electronics.Best pixel < 2 mK/Hz0.5 ( 1.1 mK/Hz0.5 if « speed read-out »)

Average 4mK/Hz0.5 4·10-16W/Hz0.5 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:

2mm2mm 1.25mm1.25mmSignal :Signal : 2-4 kHz 10 kHzNoise : Noise : 2 Hz/Hz0.5 16-20 Hz/Hz0.5

Mars flux :Mars flux : 40Jy 107Jy

S/NS/N 1000-2000 Hz0.5 500-625 Hz0.5 Sensitivity (1Hz)Sensitivity (1Hz) 20-40mJy/Hz0.5 170-210 mJy/Hz0.5 (per pixel)NEP (1Hz) estimated by sky simulator !!

IN ANY CASE IT’S MORE OR LESS WHAT WE EXPECTED BASED ON THE IN ANY CASE IT’S MORE OR LESS WHAT WE EXPECTED BASED ON THE SKY SIMULATOR RESULTS. SKY SIMULATOR RESULTS.

Exemple résultat : CygA

Exemple résultat : DR21(OH)

Spectral response (Grenoble MPI, 11/2010)

Conclusions

DETECTORSDETECTORS Clearly 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 COUNTPIXELS COUNT Much better than in 2009 (factor 4-6). Limited by the electronics. Arrays sizes will now grow according to electronics developments.

OPTICSOPTICS Same 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 FURTHER TECHNICAL RUN ? TWO SEPARATE RUNS ?A MORE « USABLE » INSTRUMENT ? WORKING ON THE BIG CAMERA ?A MORE « USABLE » INSTRUMENT ? WORKING ON THE BIG CAMERA ?HOW BIG ?HOW BIG ?

IN CASE WE GO FOR SPRING 2011 :IN CASE WE GO FOR SPRING 2011 :

CRYOSTATCRYOSTAT PULSE-TUBE (if possible)PULSE-TUBE (if possible)PIXELS PIXELS 224 per array, over a 400MHz band224 per array, over a 400MHz bandELECTRONICSELECTRONICS Baseline: LPSC2011. ROACH is backup if Baseline: LPSC2011. ROACH is backup if

LPSC is still under development. LPSC is still under development. FILTERSFILTERS from NIKA2010from NIKA2010SPLITTERSPLITTER DICHROIC (if possible)DICHROIC (if possible)DETECTORS 2mmDETECTORS 2mm Same as NIKA2010; dual-polar if dichroicSame as NIKA2010; dual-polar if dichroicDETECTORS 1mmDETECTORS 1mm Antennas or LEKIDs Antennas or LEKIDs (the best, taking into account (the best, taking into account

the number of pixels that can be actually read-out by the number of pixels that can be actually read-out by existing electronics at that time, and sensitivity)existing electronics at that time, and sensitivity)