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Daily Reports (2026/10/6-13, NIKA2 run 81, Cryo run 93)

Observers on-site: Rémi, Giorgos, Mairi, Miren

AoD: Ioannis

Operators: Pedro, Sergio

Please fill the Table with the Ar1,2,3 focus values as follows. At best, make one table per day.

• Focus sequences
  Scan nr	Target	Ar2	Ar1	Ar3	Polarized?	Notes
  20261007s25-29	Mars	1.85 mm	1.71 mm	1.70 mm	no	with run92.ini and old DAFs
  20261007s33-37	Mars	1.76 mm	1.63 mm	1.59 mm	no	with run92.ini and old DAFs
  20261007s43-47	1156+295	2 mm	1.75 mm	1.75 mm	no	with run92.ini and old DAFs
  20261007s48-52	1156+295	2.2 mm	1.75 mm	1.8 mm	no	with run92.ini and old DAFs
  20261007s53-57	1156+295	2.05 mm	1.78 mm	1.8 mm	no	with run92.ini and old DAFs
  20261007s58-62	1156+295	2.3 mm	1.85 mm	1.83 mm	no	with run92.ini and old DAFs
  20261007s65-69	1641+399	2.35 mm	1.7 mm	1.74 mm	no	with run92.ini and old DAFs
  20261007s70-74	1641+399	1.9 mm	1.75 mm	1.75 mm	no	with run92.ini and old DAFs
  20261007s75-79	1641+399	1.9 mm	1.69 mm	1.71 mm	no	with run92.ini and old DAFs
  20261007s80-84	1641+399	2.22 mm	1.93 mm	1.96 mm	no	with run92.ini and old DAFs, with the original focus script (0.4 mm steps)
  20261007s97-101	1641+399	2mm	1.5mm	1.52mm	no	with run92.ini and old DAFs, with the original focus script (0.4 mm steps), a2 not well constrained
  20261007s162-166	2200+420	1.05 mm	0.7 mm	0.71 mm	no	with run92.ini and old DAFs

  Focus sequences
  Scan nr	Target	Ar2	Ar1	Ar3	Polarized?	Notes
  20261008s1-5	Uranus	1.36 mm	1.09 mm	1.09 mm	no	with run92.ini and old DAFs
  20261008s11-15	Uranus	1.55 mm	1.09 mm	1.10 mm	no	with run92.ini and old DAFs. Starting on A1 value. Not great at 2mm. Using peak values
  20261008s16-20	Uranus	1.55 mm	1.18 mm	1.18 mm	no	with run92.ini and old DAFs. Starting on A2 value. Using peak values
  20261008s25-29	Uranus	1.51 mm	1.09 mm	1.11 mm	no	with run92.ini and old DAFs. Starting on A1 value. Using peak values
  20261008s31-35	Uranus	1.41 mm	1.14 mm	1.14 mm	no	with run92.ini and old DAFs. Starting on A2 value. Using peak values
  20261008s40-44	Uranus	1.47 mm	1.09 mm	1.08 mm	no	with run92.ini and old DAFs. Starting on A1 value. Using peak values
  20261008s45-49	Uranus	1.51 mm	1.17 mm	1.17 mm	no	with run92.ini and old DAFs. Starting on A2 value. Using peak values
  20261008s56-60	Uranus	1.32 mm	1.11 mm	1.11 mm	no	with run92.ini and old DAFs. Starting close to A2 value. Using peak values
  20261008s67-71	Uranus	1.43 mm	1.05 mm	1.06 mm	no	with run92.ini and old DAFs. Starting close to A1 value. Using peak values
  20261008s67-71	0316+413	1.34 mm	0.99 mm	0.99 mm	no	with run92.ini and old DAFs. Starting close to A1 value. Using peak values
  20261008s75-79	Uranus	1.43 mm	1.05 mm	1.06 mm	no	with run92.ini and old DAFs. Starting close to A1 value. Using peak values

Similarly, if any beam maps (total power) are taken:

• Beam maps (99 sub-scans)
  Scan Nr	Target	Focus	Notes
  20261007s30	Mars	1.71 mm (Ar1)	run93, new sweep
  20261007s39	Mars	1.63 mm (Ar1)	run93, new sweep
  20261007s181	0316+413	0.8 mm (Ar1)	run93, new sweep, pointing on ???
  20261008s8	0316+413	1.1 mm (Ar1)	run93, new sweep, pointing on Ar1
  20261008s23	Uranus	1.18 mm (Ar1)	run93, new sweep, pointing on Ar1
  20261008s38	Uranus	1.14 mm (Ar1)	run93, new sweep, pointing on Ar1
  20261008s52	Uranus	1.51 mm (Ar2)	run93, new sweep, pointing on Ar2
  20261008s63	Uranus	1.11 mm (Ar1)	run93, new sweep, pointing on Ar1
  20261008s90	Uranus	1.05 mm (Ar1)	run93, new sweep, pointing on Ar2

Please keep track of sweep changes: it makes our life easier when building the DAFs/Kidpars.

• Changes of sweep
  Sweep	Scan Nr	Time	Notes
  OLD	up to 20261007s29		for pointing & focus
  NEW	20261007s30		beammap
  OLD	20261007s31-38		for pointing & focus
  NEW	20261007s39		beammap
  OLD	20261007s42-		for pointing & focus
  NEW	20261007s180-		beammap
  OLD	20261007s182		for pointing & focus
  NEW	20261008s7-		beammap
  OLD	20261008s9		for pointing & focus
  NEW	20261008s22-		beammap
  OLD	20261008s24		for pointing & focus
  NEW	20261008s37-		beammap
  OLD	20261008s39		for pointing & focus
  NEW	20261008s51-		beammap
  OLD	20261008s55		for pointing & focus
  NEW	20261008s62-		beammap
  OLD	20261008s65		for pointing & focus
  NEW	20261008s89-		beammap
  OLD	20261008s91		for pointing & focus
  NEW	20261008s97-		beammap

Pool-Account usage: Accounting of observing times

• Calibration observations like pointing, focus, and calib_1scan (the latter in case of NIKA2-Pol only, aimed at characterizing the instrumental polarization) which are conducted before and during project observations are part of the project time. Note that all proposals include such overheads in the time and sensitivity estimates. This holds for total power and polarimetry observations.

• Other calibration observations which are important for all projects like beam maps, skydips, or calib_1scan for absolute flux calibration may be accounted under the pool account (nikaX-YY, where X = s,w and YY = year).

• When conditions are unstable and it is unclear whether project observations make sense at all, calibrations may be accounted to the pool account.

October 6th, 2026, Tuesday

10:30-15:30 : 3/4 observers arrived at the telescope. Rémi planned to arrive later today. Weather horrible. Maintenance ongoing.

Antenna parked all day, clouds, wind, and rain.

October 7th, 2026, Wednesday

07:00LT: pointing and focus tests with old sweep (run92). Difference between Ar2 and Ar1 ~0.35 mm. Difference between Ar3 and Ar1 practically 0.

10:00 - 11:30LT: new sweep by M. Calvo. We now have new run93.ini files.

11:45LT Miren and Ioanns : starting NIKA2 observations to get beammaps for the new sweep. Back to run92 for pointing and focus on Mars. DAQ started, lost KIDs Ar1/Ar2/Ar3: 129/6/14; traces look fine. Opacity between 0.3 - 0.5. Peak-to-peak in Ar2 +/- 4-5 Jy/beam. Focus differences: Ar1 - Ar2 = -0.14 mm, Ar1 - Ar3 = 0.01 mm.

12:45LT: moving to run93 for beammaps. Lost KIDs Ar1/Ar2/Ar3: 21/8/30. To be understood if box I is lost or not. Beammap (20261007s30) focused on Ar1.

13h25LT: back to run92 for pointing and focus before another beammap. Lost KIDs Ar1/Ar2/Ar3: 140/7/15. Moving back to run93 for beammaps. Beammap (20261007s39) focused on Ar1.

14h30LT Miren and Mairi: focus tests with run92. Using the original focus script (with 0.4 mm step) starting from scan 20261007s80.

16h55LT: we try a mini pointing session making use of the sources in the PCCS catalogue provided by S. Berta (we have had to remove the "G" from the names in the end... 13 characters otherwise...) Opacity is ~ 0.35 (tau225 GHz), but a lot of clouds. We can not point, p2p fluctuations @Ar2 of +/- 20 Jy/beam.

19h00LT: We resume. Sky is stable (<5 Jy/beam) and tau around 0.3.

Summary:

October 8th, 2026, Thursday

00:30LT Miren: Stable (=/-2 Jy/beam) and good opacity (~ 0.25). Better beammaps are needed. We move to 0316+413 for first beammaps, waiting Uranus to be high.

01:00 - 07:00 LT, Rémi : stable weather, clear sky and opacity ~ 0.25 for the entire shift.

• 2 beam maps on 0316+413 with focus and pointing optimized for A1, plus several pointing and focus
• 2 beam maps on Uranus with focus and pointing optimized for A1, plus several pointing and focus
• 1 beam map on Uranus with focus and pointing optimized for A2, plus several pointing and focus
• 1 skydip (using the new sweep): scan 20261008s53
• 1 beam map on Uranus with focus and pointing optimized for A1, plus several pointing and focus

• Remarks:

  • 1) the focus offset difference between A1/3 and A2 is about 0.3. However, the A2 (FWHM_x x FWHM_y)^1/2 is alway >21" and the beam is elongated: at best we have ~20"x25". The shape is not the same as the one we use to have. Issue with the current DAFs? The dichroic? Lateral focus (but this should also affect A1/3)? Other? 2) The best focus can vary by up to 0.1mm for A1/3 depending if we start from the current A1/3 or A2 value: systematic positive shift when starting with A2 value.

07:00 - 13:00 LT, Giorgos :

• finish the beammap of Remi's shift and back to old sweep
• IM: After a short chat in the morning with SB, realized that the beam maps should be pointed on Ar2 (as we do with the science observations). I tried to optimize for Ar1 (both focus and pointing), which was not the best practice (sorry!). So, the ones taken during the night with pointing on Ar1 might not be useful. There is one from the Rémi's shift that could be used (20261008s52, see beam maps table above) and I take another two with the proper setup (poi corr on Ar2, focus corr on Ar1) in the morning (20261008s90 and 20261008s98), starting at an elevation of about 35 degrees. Data processing for new DAFs are in progress by SB.
• start test scans of project 092-26. Opacity increasing. Ar2 beam very elongated.

13:00 - 19:00 LT, Mairi : Taking over shift from Giorgos. Continuing test scans for project 092-26. One repetition completed (s112 and 113). Unstable sky (+/-10Jy/beam), waiting to see if improves before continuing.

19:00 - 01:00 LP, Ioannis :

18:00 SB. I've been processing the beam maps taken during the last night/morning with good weather and on Uranus and 0316+413. The result is good for Ar1. Ar3 is still downloading and I will then process it later tonight. And about Ar2... oh well, the beam is confirmed to be very elongated, even when supposedly "on focus". The position angle (PA) of the beam ellipse is rotating in AzEl, I guess as a function of Elevation. To give you an idea, here I include the sequence of Ar2 beam maps f.o.v., in the hope that this will help the instrument/hardware experts to figure out what is happening.

October 9th, 2026, Friday

October 10th, 2026, Saturday

October 11th, 2026, Sunday

October 12th, 2026, Monday

October 13th, 2026, Tuesday