Download ppt - IRAM

Status
DETECTORS:
- We have a first baseline array (144 pixels) at 2mm. Average sensitivity: 6mK/Hz0.5 (1Hz)
Without de-correlation. In 2009 it was roughly 20mK before decorrelation.
- We have a first array at 1.25mm (Roma-Trento) to test. And others at 2mm.
- Begin of August foreseen test on first SRON array at 1.25mm
- Working to improve the 2mm IRAM-Néel 2mm array (e.g. cross-talk, thickness, HF, film)
Best pixels tested had 2.7mK/Hz0.5 (1Hz), before de-correlation.
- DECORRELATION IS PRIORITY (by eye we see a correlation)
OPTICS:
- Dual-band OK (for now no corrugated lenses and HDPE first lens)
- Polarizer should arrive this week or the next
- Still waiting one last HPE filter with the good diameter (should arrive)
- Background seems lower with the new optics (40K vs. 70K equivalent). A confirmer cet aprèm.
ELECTRONICS:
- ROACH board 64 channels version working (up to 220MHz band) (Alain DDC program)
- DDC program should work for 100 pixels
- ROACH board FFT program almost done (Loren)
- LPSC electronics will be available too for October (128 ch. but only 120MHz band)
- The NIKA FFTS Bonn box never arrived
- Andrey working on another electronics (purely commercial, 1GHz band)
For 6mK difference T on focal plane we calculate (assuming 0.35 instrument
Transmission and 130-165GHz band) 5.5·10-16 W difference per pixel (2.25x2.25mm)
DECORRELATION VERY IMPORTANT.
3-6dB deep  coupling OK
Problem. 2-3 resonances lost.
Process : IRAM (sputtering), 30nm, HR silicon, 300um thick.
Design : NICA 5a
FWHM = 28mm (??? Typical 20 ??)
S/N on the « planet » = 3000 Hz0.5
Assuming T=20K (200K of 8mm
diameter planet diluted over 28mm
beam), means
20K/3000  7mK/Hz0.5
  consistent with Sky simulator
estimation
TELESCOPE
FOCAL PLANE
TELESCOPE
LABORATORY
620 mm