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NIKA November 2012 S2

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2012-11-15

Cryostat Temperature: 150 +/- 0.02 mK (regulated with power 50uW), looks to be a better compromise between 2mm array and 1mm array optimal temperature.
Arrays status tonight: 126 pixels 2mm - good noise; 90 pixels 1mm noise 2x optimal (limited number of pixels and excess noise due to cold amplifier saturation --> -62dBm per KID instead of -50dBm).

Nasmyth offsets : 0, 0

Set pointing : 0, 0

Set Focus : -2.40 mm

Quick description of the session: Test the Pako sequences, data flows, and generation of IMBFITS. Start observing procedures described in ListOfAstroTarget2012N5.
At 20h40 UT: the sky was stable enough to check the alignment radiometrically by measuring the background on the sky and finding the minimum (spill over the primary) by moving M5; conclusion: we were slightly misaligned previously, with the new position of M5 we gained ~2K on the background.

Scan	UT	Source	Command	Az	El	Pointing X, Y, Focus	Tau	Comment
60	16h17	Mars	Track	207	23		0.2
61	16h30	Mars	OTF_geomfast	209	22		0.22	420"x 220" (step 6") in 36 subscans x 14 s = 9+3 ~= 12 min
62	16h47	Neptune	Track	144	33		0.20
63	16h49	Neptune	OTF_geomfast	145	34		0.20
64	17h05	Neptune	OTF_2x2	149	35		0.20
65	17h23	DIY-Tip	DIY-Tip				0.20	Hans test of Sky dip with tune
66	17h	DIY	DIY				0.20	Hans test of tune
67	17h	DIY-Tip	DIY-Tip				0.20	Hans test of Sky dip with tune
68	17h51	Uranus	Track	120	35		0.10
70	17h58	Uranus	OTF_geometry	121	36		0.12	stopped because there were tunnings durin the scan
71	18h02	Uranus	OTF_geometry	122	37		0.12	300"x 220" (step 4") in 56 subscans x 20 s = 19+3 ~= 22 min.
72	18h35	Uranus	OTF_geometry	122	37		0.12	redo because telescope stuck at middle of scan 71
73	18h39	Uranus	OTF_geometry	122	37		0.12	telescope stopped again, impossible to move it, AS investigate
74	19h15	Uranus	OTF_geometry	122	37		0.12	AS solved the problem
75	19h25	Uranus	OTF_geom_below70degEl	145	49		0.12	try a fast geom 35"/s, 420" large Az base, 4" El step
76	19h40	Uranus	OTF_geom_below70degEl	145	49		0.11	same as above
77	20h	Uranus	Cross	160	52		0.12	Cross scan to determine Nastmyth pointing offset
78	20h30	Uranus	OTF_2x2	169	53		0.12	small OTF to accumulate statistics while Nicolas work on the cross
	20h40							Optimize radio alignment moving M5 micrometric screws, minimize background => gain 2K
79	20h56	Uranus	Cross	160	52		0.12	found -3 3 offset on scan 77, but redo with 0 0 since M5 has moved
80	21h07	Uranus	Cross	160	52		0.12	with pointing offset3 3 to check Nicolas calculation
81	21h11	Uranus	Cross	160	52		0.12	redo same, high sky noise on previous scan
82	21h19	Uranus	Cross	160	52		0.12	do a 2nd one to check stability
83	21h27	Uranus	Cross	160	52		0.12	set pointing 6 6
84	21h27	Uranus	Cross	160	52		0.12	set pointing 8.64 10.67 => pixel 453 2mm should be at center => it works
85	21h37	Uranus	Focus 2	160	52		0.12	test a focus (procedure to reduce it not ready, but needed for the test)
86	21h47	0316+413 = 3C84	Track	69	65		0.12	start accumulate stat on pointing
87	21h50	0316+413 = 3C84	Cross	69	65		0.12	remark: focus not reduced but had 17" FWHM on 2mm crosses => should be correct for 1st iteration on pointing
88	21h53	0528+134	Track	38	116		0.1
89	21h56	0528+134	Cross	38	116		0.1
90	21h58	0528+134	Cross	38	116		0.1	redo: source too weak on 1st cross profile
91	22h00	0235+164	Track	65	140		0.1
92	22h03	0235+164	Cross	65	140		0.1
93	22h05	2251+158 = 3C454.3	Track	250	48		0.07
94	22h14	2251+158 = 3C454.3	Cross	250	48		0.07	acquisition crashed
95	22h17	2251+158 = 3C454.3	Cross	250	48		0.07	redo
96	22h20	Uranus	Track	215	48		0.07	Goal: redo an OTF geometry since we moved M5
97	22h23	Uranus	Cross	215	48		0.07	take the occasion to use as pointing
98	22h26	Uranus	Focus	215	48		0.07	take the occasion to have a 2nd focus scan for Nicolas
99	22h28	Uranus	OTF_geom_below70degEl	215	48		0.07	geometry
100	22h44	Uranus	OTF_geom_below70degEl	222	45		0.07	geometry