Diff for "PrepRun7" - www.iram.es Main Wiki

Differences between revisions 32 and 52 (spanning 20 versions)

November 11th 2013, Alain Benoit, Martino Calvo and Andrea Catalano come to the 30m to install, cool down and testing the NIKA prototype.

12-13 November 2013: cryostat and Read-Out positioning in the cabin, cooling down, HWP Modulator installation at the pupil (120mm from the entrance lens of the cryostat).

14 November 2013: OTF geometries on Mars and Uranus. Check of the focal plane geometry. First light of NIKA prototype with polarisation facilities. In the afternoon tests on the power on the pixels check its uniformity on the 2 arrays.

15 November 2013: Cryostat back to 300K: 3He-4He mix recovery, heating trap. Polarisation facilities dismantling. Back to Granada.

STATUS

Cryostat Temperature: 150mK (set by temperature control).

Arrays: 130 (129 good) pixels 2mm - about 1Hz/sqrtHz noise (sky with tau about 0); 201 (about 185 good) pixels 1mm - about 5Hz/sqrtHz noise (sky with tau about 0); The tests for the optimal power where conducted with the window closed with some alu foil -> not great in term of stability, could add some 1/f. Touching the foil made a clear signal (at least on the 1mm). The final values for the different DAC gains can be seen in this image:

Figures: Settings of the 2 arrays. In red, NIKEL1 = 1mm, in blue NIKEL2 = 2mm.

Modulation frequency: 8kHz 1mm, 5kHz 2mm

OBSERVATIONS Log

Opacity is measured with the taumeter at 225 GHz

p2cor : 0

p7cor : 0

initial Focus : -2.40 mm

Scan	UT	Source	Command	Az	El	Pointing X, Y, Focus	Tau225	Comment
15	04h39	Mars	Track			0 , 0 , -2.4	0.15
16	04h45	Mars	OTF_Geometry			0 , 0 , -2.4	0.15	First map for choosing the reference pixels
17-21	04h58-05h04	Mars	Focus_Liss			0, 0, -2.4	0.15
22	05h05	Mars	Focus			0, 0, -2.4	0.15
23	05h47	Mars	OTF_Geometry			0, 0, -2.4	0.15	Tuning working during the map
211-218	21h34-21h57	Uranus	Track 300 300	55	190	0, 0, -2.4	0.00001
220-224	22h01-22h08	Uranus	Focus_Liss			0, 0, -2.4	0.00001	optimal focus probably over the range
225	22h10	Uranus	Cross			0, 0, -2.4	0.00001
226-230	22h12-22h18	Uranus	Focus_Liss			0, 0, -1	0.00001	set pointing Az=-12.8 El=3.8 set focus = -1.5
231	22h24	Uranus	OTF_Geometry			-12.8, 3.8, -1.5	0.00001
232	22h49	Uranus	OTF_Geometry			-12.8, 3.8, -1.5	0.00001	HWP+Pol (Geometry probably lost)
241-245	23h34-23h47	others observing	various					HWP+Pol+Cryostat in the cabin environment

FIRST RESULTS

Figures: Focal Plane Geometry derived using scan 16: we chose the following reference pixels: 491 for 2mm array, 5 for 1mm array.

Figures: 1mm array from scan 231.

Figures: 2mm array from scan 231.

Figures: Entire (top) and zoomed (bottom) Timeline of the scan 232 on Uranus in configuration NIKA + HWP-Pol

Further results on polarisation measurements will come soon.......

-  ⇤ ← Revision 32 as of 2013-11-15 05:11:08 → 
  Size: 3055
  Editor: NikaBolometer
  Comment:
+   ← Revision 52 as of 2013-11-15 09:16:46 → ⇥
  Size: 4250
  Editor: NikaBolometer
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 7:
-'''12-13 November 2013''': cooling down, HWP Modulator installation at the pupil (120mm from the entrance lens of the cryostat)
+'''12-13 November 2013''': cryostat and Read-Out positioning in the cabin, cooling down, HWP Modulator installation at the pupil (120mm from the entrance lens of the cryostat).
 Line 9:
-'''14 November 2013''': OTF geometries on Mars and Uranus. Check of the focal plane geometry. First light of NIKA prototype with polarisation facilities.
+'''14 November 2013''': OTF geometries on Mars and Uranus. Check of the focal plane geometry. First light of NIKA prototype with polarisation facilities. In the afternoon tests on the power on the pixels check its uniformity on the 2 arrays.
 Line 18:
-'''Arrays status''':  128 pixels 2mm - <1Hz/sqrtHz noise; 201 pixels 1mm about 10Hz/sqrtHz noise
+'''Arrays''':  
130 (129 good) pixels 2mm - about 1Hz/sqrtHz noise (sky with tau about 0); 
201 (about 185 good) pixels 1mm - about 5Hz/sqrtHz noise (sky with tau about 0);
The tests for the optimal power where conducted with the window closed with some alu foil -> not great in term of stability, could add some 1/f. Touching the foil made a clear signal (at least on the 1mm).
The final values for the different DAC gains can be seen in this image:
-Line 20:
+Line 24:
-'''Modulation frequency''': 8kHz 1mm, 4kHz 2mm
+{{attachment:DACgains.png||width=800}}

''Figures: Settings of the 2 arrays. In red, NIKEL1 = 1mm, in blue NIKEL2 = 2mm.''

'''Modulation frequency''': 8kHz 1mm, 5kHz 2mm
-Line 26:
+Line 34:
-Opacity is measurd with the taumeter at 225 GHz
+Opacity is measured with the taumeter at 225 GHz
-Line 46:
+Line 54:
-||  232      ||   22h49  || Uranus      || OTF_Geometry  ||        ||        ||       -12.8, 3.8,  -1.5        ||   0.00001         || HWP+Pol  ||
||  241-245      ||   23h34-23h47  || other observing      || various  ||        ||        ||      ||          || HWP+Pol+Cryostat in the cabin environment   ||
+||  232      ||   22h49  || Uranus      || OTF_Geometry  ||        ||        ||       -12.8, 3.8,  -1.5        ||   0.00001         || HWP+Pol (Geometry probably lost) ||
||  241-245      ||   23h34-23h47  || others observing      || various  ||        ||        ||      ||          || HWP+Pol+Cryostat in the cabin environment   ||
-Line 55:
+Line 63:
-''Figures: NIKA installed again.''
+''Figures: Focal Plane Geometry derived using scan 16: we chose the following reference pixels: 491 for 2mm array, 5 for 1mm array.''


{{attachment:1mm.png||width=900,height=550}}

''Figures: 1mm array from scan 231.''

{{attachment:2mm.png||width=900,height=550}}

''Figures: 2mm array from scan 231.''


{{attachment:pol1.png||width=600}}
{{attachment:pol2.png||width=600}}

''Figures: Entire (top) and zoomed (bottom) Timeline of the scan 232 on Uranus in configuration NIKA + HWP-Pol''

'''Further results on polarisation measurements will come soon.......'''