Differences between revisions 1 and 14 (spanning 13 versions)
⇤ ← Revision 1 as of 2016-01-12 13:13:00 →
Size: 109
Editor: NikaBolometer
Comment:
← Revision 14 as of 2016-01-14 14:42:59 → ⇥
Size: 3598
Editor: NikaBolometer
Comment:
Deletions are marked like this. Additions are marked like this.
Line 5: Line 5:
== January 2016, 12 (Tuesday)
== January 2016, 14 (Wednesday) ==

01h30. We go to the sky. Telescope staring at EL = 43 deg under tau = 0.2-0.25 and good conditions in stability.

We first measured the shift between the window and the sky (say 50K), then we have measured the shift between the window and the 300K of the cabin (say 300K UPPER limit). The box B is measuring strangely. But on the others we conclude that:

'''2mm:''' 400kHz shift for 300K so '''1.3kHz/K'''

'''1mmV (NIKEL DC):''' 650kHz for 300K so roughly '''2.2kHz/K'''

'''1mmH (NIKEL RF):''' 800KHz for 300K so '''2.7kHz/K'''

See the noise and comments below for S/N and mK/sqrt(Hz) sensitivity.



{{attachment:shiftwindsky.png||height=600}} {{attachment:shiftwind300K.png||height=600}}

'''Figure.''' Left: shifts between window (0K) and Sky tau 0.2, elevation 43 deg (say 50K ?). Right: shifts between window (0K) and 300K of the cabin.


The noise on the sky seems OK (say great) on the arrays 1 (1mm NIKEL RF) and 2 (2mm). Worse on array 3 (1mm NIKEL DC).


{{attachment:2mmnoisesky.png||height=480}} {{attachment:1mm1noisesky.png||height=480}} {{attachment:1mm3noisesky.png||height=480}}

'''Figure.''' Noise on the sky on respectively the 2mm, 1mm NIKEL_RF (array 1) and 1mm NIKEL_DC (array 3).


'''ROUGH T SENSITIVITY CALCULATION:'''

Say the noise is 2Hz/sqrt(Hz), 1.3Hz/sqrt(Hz) and 3Hz/sqrt(Hz) for the three arrays respectively. The sensitivities are thus:

'''2mm: (1.3/1300) K/sqrt(Hz) = 1 mK/sqrt(Hz) per pixel'''

'''1mmV (DC): (3/2200) K/sqrt(Hz) = 1.4 mK/sqrt(Hz) per pixel'''

'''1mmH (RF): (2/2700) K/sqrt(Hz) = 0.75 mK/sqrt(Hz) per pixel (!!!)'''


So the response is good, as calculated in laboratory, as well as the noise at the end. Still to check if these photons to whose we are so sensitive are correctly focalised.



== January 2016, 13 (Wednesday) ==

19h30. NIKA2 HAS ALL THE 20 LINES CONNECTED AND ALL WITH RESONANCES. WE ENTERED THE 3000 PIXELS ERA.

THE NOISE (with the window) seems OK. On three random lines over the three arrays I see on average 1Hz/sqrt(Hz) (2mm), 2Hz/sqrt(Hz) (1mm, NIKEL_RF) and 2.5Hz/sqrt(Hz) (1mm, NIKEL_DC). Very flat on the 2mm one, a bit less on the 1mm ones. Still no traces of the pulse tube. I think that the difference between the noise on the NIKEL_Rf and the NIKEL_DC can be explained with the modulation. The nominal 10kHz modulation on the NIKEL_RF are in reality 6.5kHz, while on the other RF source attached to the NIKEL_DC we have 9.5kHz. Or viceversa. So the RF_dIdQ is calculated a bit differently. So my conclusion is that most probably there is no real difference between the two configurations.


{{attachment:2mmnoisewindow.png||height=480}} {{attachment:1mm1noisewindow.png||height=480}} {{attachment:1mm3noisewindow.png||height=480}}

'''Figure.''' Noise with the window on respectively the 2mm, 1mm NIKEL_RF (array 1) and 1mm NIKEL_DC (array 3)


{{attachment:tracearray3.png||height=515}} {{attachment:monitor3pixels.png||height=515}}

'''Figure.''' Left: trace of the 1140 pixels of array 3; right: monitor with all the 20 boards tuned.

Next step on the sky at 2am to check resonances shape.

== January 2016, 12 (Tuesday) ==
 * Olivier, Alessandro and Florian arrived at the telescope.

The new boards installed and connected

Array 1 (1mm - IN-OUT 5-12): NIKEL_RF (192.168.1.150)

Array 2 (2mm - IN-OUT 1-4): NIKEL_USB (192.168.1.221-24)

Array 3 (1mm - IN-OUT 13/20): NIKEL_DC (192.168.1.170)

Back to the NIKA2 run 3 main page

Contents

  1. January 2016, 14 (Wednesday)
  2. January 2016, 13 (Wednesday)
  3. January 2016, 12 (Tuesday)

January 2016, 14 (Wednesday)

01h30. We go to the sky. Telescope staring at EL = 43 deg under tau = 0.2-0.25 and good conditions in stability.

We first measured the shift between the window and the sky (say 50K), then we have measured the shift between the window and the 300K of the cabin (say 300K UPPER limit). The box B is measuring strangely. But on the others we conclude that:

2mm: 400kHz shift for 300K so 1.3kHz/K

1mmV (NIKEL DC): 650kHz for 300K so roughly 2.2kHz/K

1mmH (NIKEL RF): 800KHz for 300K so 2.7kHz/K

See the noise and comments below for S/N and mK/sqrt(Hz) sensitivity.

shiftwindsky.png shiftwind300K.png

Figure. Left: shifts between window (0K) and Sky tau 0.2, elevation 43 deg (say 50K ?). Right: shifts between window (0K) and 300K of the cabin.

The noise on the sky seems OK (say great) on the arrays 1 (1mm NIKEL RF) and 2 (2mm). Worse on array 3 (1mm NIKEL DC).

2mmnoisesky.png 1mm1noisesky.png 1mm3noisesky.png

Figure. Noise on the sky on respectively the 2mm, 1mm NIKEL_RF (array 1) and 1mm NIKEL_DC (array 3).

ROUGH T SENSITIVITY CALCULATION:

Say the noise is 2Hz/sqrt(Hz), 1.3Hz/sqrt(Hz) and 3Hz/sqrt(Hz) for the three arrays respectively. The sensitivities are thus:

2mm: (1.3/1300) K/sqrt(Hz) = 1 mK/sqrt(Hz) per pixel

1mmV (DC): (3/2200) K/sqrt(Hz) = 1.4 mK/sqrt(Hz) per pixel

1mmH (RF): (2/2700) K/sqrt(Hz) = 0.75 mK/sqrt(Hz) per pixel (!!!)

So the response is good, as calculated in laboratory, as well as the noise at the end. Still to check if these photons to whose we are so sensitive are correctly focalised.

January 2016, 13 (Wednesday)

19h30. NIKA2 HAS ALL THE 20 LINES CONNECTED AND ALL WITH RESONANCES. WE ENTERED THE 3000 PIXELS ERA.

THE NOISE (with the window) seems OK. On three random lines over the three arrays I see on average 1Hz/sqrt(Hz) (2mm), 2Hz/sqrt(Hz) (1mm, NIKEL_RF) and 2.5Hz/sqrt(Hz) (1mm, NIKEL_DC). Very flat on the 2mm one, a bit less on the 1mm ones. Still no traces of the pulse tube. I think that the difference between the noise on the NIKEL_Rf and the NIKEL_DC can be explained with the modulation. The nominal 10kHz modulation on the NIKEL_RF are in reality 6.5kHz, while on the other RF source attached to the NIKEL_DC we have 9.5kHz. Or viceversa. So the RF_dIdQ is calculated a bit differently. So my conclusion is that most probably there is no real difference between the two configurations.

2mmnoisewindow.png 1mm1noisewindow.png 1mm3noisewindow.png

Figure. Noise with the window on respectively the 2mm, 1mm NIKEL_RF (array 1) and 1mm NIKEL_DC (array 3)

tracearray3.png monitor3pixels.png

Figure. Left: trace of the 1140 pixels of array 3; right: monitor with all the 20 boards tuned.

Next step on the sky at 2am to check resonances shape.

January 2016, 12 (Tuesday)

  • Olivier, Alessandro and Florian arrived at the telescope.

The new boards installed and connected

Array 1 (1mm - IN-OUT 5-12): NIKEL_RF (192.168.1.150)

Array 2 (2mm - IN-OUT 1-4): NIKEL_USB (192.168.1.221-24)

Array 3 (1mm - IN-OUT 13/20): NIKEL_DC (192.168.1.170)

DailyReportsNika2Run3 (last edited 2016-03-24 23:05:28 by NikaBolometer)