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Daily Reports (2026/01/13-20, NIKA2 run 78, Cryo run 90)

Observers on-site: Ste B, Cheng Yu, Rubén Fedriani, Paul Law, Andrea Bracco

Astronomer on Duty: Ioannis Myserlis
Pool Manager: Angel Bongiovanni

Operators: Joaquín Santiago (day) and Gloria Liñan (night)

Organization of shifts:
03:00-09:00 UT: Stefano Berta
09:00:15:00 UT: Cheng Yu and Rubén Fedriani
15:00-21:00 UT: Paul Law
21:00-03:00 UT: Andrea Bracco

Important

Focus offsets shall be measured on Ar1
Pointing offsets shall be measured on Ar2

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 ; nikaw-25 in this case).

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

Focus and Beam maps accounting

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

• Focus sequences (NOTE: Ar2 is very noisy and this might influence the A2 focus value)
  Scans nr.	Target	Ar2	Ar1	Ar3	Pol?	Notes
  20260115s2-6	3C273	0.30	uhm	out	no	started at 1.0 mm; Ar1 only marginally covered by the focus range -> re-do
  7-11	3C273	out	1.31	1.54	no	started at 1.4 mm;
  42-46	1757-240	out	1.22	1.41	no	started at 1.6 mm;
  53-57	MWC349	0.48	1.47	out	no	started at 1.22 mm
  70-74	2251+158	out	1.42	1.62	yes	started at 1.47 mm
  104-108	Neptune	out	1.30	1.50	yes	started at 1.42 mm
  20260117s3-7	1757-240	out	2.02	2.22	no	started at 2.1 mm (de-icing stopped 1h ago)
  ...?
  41-45	Uranus	0.77	1.4	1.58	yes	started at 1.8 mm
  58-62	Uranus	out	1.06	1.28	yes	started at 1.4 mm
  64-68	Uranus	0.23	1.05	1.30	yes	started at 1.0 mm
  80-84	Uranus	0.62	out	out	yes	started at 0.9 mm -> re-do
  85-89	Uranus	out	1.62	1.85	yes	started 1.9 mm, outside temperature dropped to -12 C
  100-104	Uranus	0.73	1.65	1.94	yes	started 1.62 mm, Ar2 flux only
  114-118	Uranus	out	1.45	1.66	yes	started 1.65 mm
  20260118s16-20	3C286	out	1.05	1.32	yes	started 1.45mm
  32-36	3C279	out	1.03	1.22	no	started at 1.3 mm
  41-45	3C279	0.1	out	out	no	started at 0.3 mm (focusing Ar2 for beam map)
  49-53	3C279	out	1.01	1.21	no	started at 1.3 mm, Ar2 FWHM only
  70-74	1757-240	out	0.94	1.15	no	started at 1.5 mm
  80-84	1757-240	out	1.3	1.55	no	started at 2.2 mm, Ar1 FWHM only
  91-95	2251+158	0.40	1.41	1.73	yes	started at 1.3mm
  114-118	Neptune	out	out	1.0	yes	started at 1.6 mm -> re-do
  119-123	Neptune	out	0.76	0.95	yes	started at 1.0 mm
  167-171	Uranus	out	0.78	1.15	no	started at 0.76mm
  20260119s3-7	Uranus	0.04	0.89	1.11	yes	started at 0.78mm
  32-36	3C279	0.21	1.05	1.29	no	started at 1.1 mm Ar2 FWHM only and marginal
  41-45	3C279	0.05	out	out	no	started at 0.3 mm (looking for Ar2 focus for beam map); Ar2 flux only; broad Ar2 beam
  48-52	3C279	out	1.05	1.27	no	started at 1.3 mm
  61-65	1757-240	-0.21	0.85	1.07	no	started at 1.05 mm; Ar2 FWHM only
  70-74	1757-240	0.05	1.00	1.21	no	started at 0.85 mm; Ar3 FWHM only
  82-86	2251+158	0.21	1.23	1.47	yes	started at 1.3 mm, Ar2 FWHM only
  138-142	Uranus	out	0.86	1.10	yes	started at 1.6 mm; Ar1 FWHM only

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

• Beam maps
  Scan Nr	Target	Focus	TP (99 subscans) or Pol (95 subscans)	Notes
  20260118s38	3C279	1.03 (Ar1)	TP (99)	Focus optimized for Ar1 (i.e. standard choice in the S25 and W25 semesters)
  40	3C279	1.22 (Ar3)	TP (99)	Focus optimized for Ar3 [Ar1 Box I is KO]
  47	3C279	0.10 (Ar2)	TP (99)	Focus optimized for Ar2
  20260119s38	3C279	1.05 (Ar1)	TP (99)	Focus optimized for Ar1
  40	3C279	1.29 (Ar3)	TP (99)	Focus optimized for Ar3
  47	3C279	0.05 (Ar2)	TP (99)	Focus optimized for Ar2; be aware of broad Ar2 beam in the focus sequence; wind?

Tuesday, 13th January 2026

9:30-14:30 UT: Maintenance time. The team arrived at the telescope, only Andrea is missing.

14:30-00:00 UT: Stopped due to high wind, fog and snow. In the afternoon we had a training session on NIKA2 observations with on-site observers.

Wednesday, 14th January 2026

00:00-9:00 UT: Still stopped. Snowing in the morning.

09:00-13:00 UT still stopped for wind and thick clouds

12:30-14:15 UT: Sky clears up a bit so we start with EMIR backup observations of project 150-25 at ~13:00 UT. This is the only project available for observations right now, even if it <15 deg away from the Sun, keeping in mind that E150 is not working. Anyway, after 1 hr the weather is getting bad again (pwv >= 10mm) and we park the telescope once more.

14:15-20:00 UT: Telescope stopped. Bad weather.

20:00-04:00 UT: Telescope parked. No night operator until tomorrow due to personal reasons.

Thursday, 15th January 2026

03:45-09:00 UT Stefano:

• @03:45 we start the NIKA2 total power observations; lost KIDs: 20/7/24; tau(225)=0.27; temperature -8 C; wind 2 m/s. Stability: peak to peak sky variation along the timelines < +/- 0.5 Jy/beam on pointing scans @2mm.

• 197-25 four repetitions of CL3. Note: the first three repetitions were taken with 47 Hz sampling. No big deal: actually they'll be less affected by sky "instabilities".
• 166-25 one repetition of GC1. Lots of haze in the l.o.s. in the second scan. We do not observe 166-25 any further.

09:00-15:00 UT Ruben and Cheng (+ Stefano and Ioannis):

• calibrations: MWC349 (scan 58), NGC7027 (scan 59), CRL 2688 (scan 60), Skydip (scan 61)
• 166-25 one repetition on GC3.
• @11:15 UT we switch to polarimetry. Lost KIDs 12/6/20.
• 140-25 one repetition on Cloud D, using 2251+158 (3C454) as IP calibrator
• @13:40 the imbf of scan 92 is not being produced by the new make-imbf. We do not stop/restart it, so that the people in charge of it can directly see "live" what is happening. Meanwhile we use the old make-imbf. If in half an hour is not back, SB will stop/restart it. 15 minutes lost waiting fro the old make-imbf to produce the pointing (scan 92) file. @14:00 UT Jean confirms that he has seen that there is a problem and Stefano restarts the new mak-imbf. Back to normal.
• 140-25 one repetition of Cloud G, using 2251+158 (3C454) and Neptune as IP calibrators

@11:00 UT Andrea arrives at the telescope, safe and sound.

15:00-21:00 UT Paul:

• Finishing 140-25 with pointing and calib_1scan with 2251+158 (3C454) and Neptune
• Move to project 170-25 staying on Polarimetry.
• Pointing , focus using Neptune (15:11 UT)
• Thick fog arriving at 15:33 UT time.
• Stability is very poor +/- 50 Jy/beam and moving the telescope to parking position...

@16:00 UT little experiment, taking advantage of the poor weather:

1. scan 113: normal pointing on 0316+413
2. scan 114: gently knock on the cryostat with the handle of a screwdriver, at 1-2 Hz frequency
3. scan 115: gently knock on the cryostat with the handle of a screwdriver, at 5-10 Hz frequency
4. scan 116: caressing/sweeping the cryostat with the handle of a screwdriver
5. scan 117: inserting the handle of the screwdriver between the cryostat and the ladder, such that they touch
6. scan 118: same as 4., but dancing with pretty NIKA (2!)

None of these reproduced what we have experienced last week

21:00-03:00 UT Andrea:

• Bad weather. High opacity, fog and snow. Telescope stopped.

Friday, 16th January 2026

03:45-09:00 UT Stefano:

• Still stopped. Wind, snow and frozen rain in the morning.

09:00-15:00 UT Ruben and Cheng:

• Still stopped: Wind, snow and frozen rain.

15:00-21:00 UT Paul:

• Still stopped: snow and wind.
• @15:30 UT the AoD moves to Granada and will continue his work remotely.
• @17:00 UT The taumeter is frozen and marks low.
• @19:00 UT the operator cleans the taumeter

21:00-03:00 UT Andrea:

• Still stopped. Wind and frozen rain.

Saturday, 17th January 2026

03:45-09:00 UT Stefano:

• Still stopped. Wind and frozen rain.
• @07:00 UT the sky is clear. There is ice on the lower part of the primary dish, and ice stalagmites on the sub-reflector. The de-icing is on, but we have to wait for the Sun to help melting the ice.
• @07:30 UT the operator cleans the taumeter

09:00-15:00 UT Ruben and Chen (+ Stefano):

• @10:30 UT we start with TP, Lost KIDs 12/7/14 WOW; outside temperature -10 C, no wind.
• the beam/focus is still quite affected by the de-icing (stopped 1h ago), hence low-priority TP first
• 166-25 one rep of GC2
• @11:45 UT we switch to polarimetry, it takes 3 attempts and a reboot of the mmpsync server to make things work; lost KIDs: 15/6/17.
• 140-25 0.25 repetitions of CloudG. Paul realizes that the coordinates of CloudG in the catalog are wrong and different from those in the proposal. We delete the next 3 scans from the queue and put CloudG on hold until a change of coords is approved. We switch to CloudE.
• 140-25 two repetitions of CloudE.
• @15:00 UT we stop the telescope because we're in the clouds. Just in time.

15:00-19:30 UT: Paul:

• Restarting at 16:00 UT and cont. on polarimetry project 170-25
• 170-25 two reps of Tycho

19:30-03:00 UT Andrea:

• quick training with Stefano
• outside temperature dropped to -12 C, the focus changed a lot
• 015-17 observations, using Uranus as IP calibrator, until it is available and then 3C286
• 015-17 two reps of NGC1333S
• two reps of NGC2024S3
• started one rep of NGC2264D, that will continue in the next shift (see below)

NOTE a posteriori by Stefano and Andrea (2026/01/18): the new make-imbf did not produce the imbf of several 015-17 scans, for example 20260117s110, while the old make-imbf did.

Sunday, 18th January 2026

03:00-09:00 UT Stefano:

• I let the current scan of 015-17 NGC2264D finish (1/3) and I delete the next two from the queue because El<~30. I then complete the 015-17 session with calib_1scan on 3C286 and 3C279 (different El).

• @03:45 UT switch to total power. Lost KIDs 14/8/27.
• 3 beam maps on 3C279, focused on Ar1 (scan 38), Ar3 (scan 39) and Ar2 (scan 47), respectively.
• the new make-imbf "gets stuck" on the beam maps again: it does not produce them and does not produce the next scans (pointing/focus) either. Therefore, I produce the imbf of pointings manually. Then I restart the proper make-imbf (new) after waiting 34 minutes after the end of the first beam map (i.e., I restart it after the end of the second beam map). Remarkably, the imbf's of thethird beam maps are produced regularly.
• during the 2nd beam map, box I (Ar1) is dead. I hope that during the whole 1st beam map it was OK. I check scan 39 (pointing after the 1st beam map): box I was OK. Fiuuu. A simple reboot of the DAQ is sufficient to bring it back to life. Lost KIDs 10/10/19.
• skydip (scan 48). Usual alarms at sub-scans 9-10-11.
• 197-25 two reps of Cl3
• 166-25 started one rep on GC2 with alternative tilt angles

09:00-15:00 UT Ruben and Chen (+ Stefano):

• 166-25 completed the rep on GC2
• the new make-imbf got stuck on scan 78 (last scan produced 76; scan 77 was cancelled; scan 78 was not produced)
• 166-25 one rep on GC3 (standard tilt)
• @10:40 we switch to polarimetry. Lost KIDs: 10/8/18.
• 140-25 0.75 reps on CloudE (we avoid the 4th scan because of clouds)

• Clouds everywhere excpet in the N direction -> we try 170-25 that is in that region.

• 170-25 the clouds arrived also to the N side. A pointing shows p2p of +/- 40 Jy/beam @2mm.
• @12:40 UT therefore we stop for a while to see how the situation evolves.

15:00-21:00 UT: Paul (+ Stefano):

• @15:30 UT we give it a try, pointing Neptune. Peak to peak sky variation along the timelines +/- 3 to 5 Jy/beam @2mm in this direction. The sky is slowly clearing up.
  • We prepare the focus and see if it becomes stable enough for observations. The taumeter is spiky because there are low clouds in its direction. On the other hand at high El and especially in the N direction, the sky is clear. "tau" at this point in only a number. We proceed.
• 170-25 two reps of Tycho, with IP calibrators Neptune, 3C454 (2251+158) and Uranus.
• @18:58 UT we switch to total power. Lost KIDs: 14/7/16.
• some calibrations: Uranus (scan 146), Neptune (scan 149), Betelgeuse (scan 152)
• very stable focus
• 110-25 one rep of S284-2

21:00-03:00 Andrea:

• Kept project 110-25. Done focus on Uranus. Good focus.
• Second and third reps of S284-2.
• skydip @23:39 UT in the pool account
• Total power to polarization @01:10 (bad kids 15/6/20 for ar1/2/3)
• go to Uranus point and focus, out of the pool project.
• Start with B-FUN (015-17)
• calib1scan on Uranus (El 29) that will need to calibrate the following calib1scan on the QSO
• calib1scan on 3c273 which will be used to close the rep on ngc2264D

• I started a second rep on the same source that will stay at >30 El for more than half of the rep.

• I close the rep with a calib1scan on 3c279. During the shift the opacity was stable < 0.2.

Monday, 19th January 2026

03:00-09:00 UT Stefano:

• complete the last rep and IP calibration of 015-17, started in the previous shift
• @03:45 UT switch to total power. Lost KIDs 14/12/11
• beam maps on 3C279: focused on Ar1 (scan 38); focused on Ar3 (scan 40), focused on Ar2 (47)
• the new make-imbf behaves like yesterday: imbf of 1st beam map not produced. This time I restart it after few minutes (I'm sick of waiting). Meanwhile, I produce manually the imbf of the pointing between the 1st and 2nd beam maps. If necessary, I'll do the same for the 2nd and 3rd beam maps, but I won't write it again here. I report to the new-make-imbf relevant people.
• @05:30 UT it starts to be windier. The IRAM's anemometer is "dead". The neighbor's shows 10 m/s gusts for now.
• 197-25 starting one rep on Cl3, but I have the feeling we'll have to stop because of the wind. Let's see
• @06:30 UT we have to stop and park the telescope because of the wind, after 2/6 scans of the repetition.
• tau(225)=0.12; wind 23 m/s and increasing. Sigh!
• @08:00 UT the wind is slightly milder, we try a pointing in the opposite direction wrt the where the wind comes from. Nope: it's still too string.

09:00-15:00 UT Chen:

• the wind velocity has decreased. We try again and now it's fine to observe. We observe in the direction opposite to where the wind comes from.
• 166-25 one rep of GC1 and GC3 with alt. tilt
• the new make-imbf is hanging/stuck: it did not produce scans 67 and 68. Stefano restarts it.
• @11:40 UT we switch to polarimetry. Lost KIDs 15/6/12.
• 140-25 1.5 reps of CloudE, using 2251+158 (3C454) and Neptune as IP calibrators.
• in this position, the tracking works well even with strong wind (up to 22 m/s). We keep the telescope with the wind at its back.
• 140-25 one rep of CloudG
• Move to project 170-25

15:00-21:00 UT: Paul + Stefano:

• @15:36 UT we cont. in polarimetry with project 170-25 using Neptune and 2251+158 (3C454) as IP calibrators.
• tau remains to be superb tau@225 ~0.11
• 170-25 three reps on Tycho
• @20:15telescope tour while Stefano switches to total power and starts 110-25. I'll have dinner later. ROFLWP. Lost KIDs: 12/10/8
• 110-25 one rep on S284-2

21:00-03:00 UT Andrea:

• 110-25 one more rep on S284-2 (already sent in the queue by Stefano)
• in the account of nika2 pool, @skydip

• @23:00 UT We switch to polarization (Lost KIDs 13/5/13). Opacity very stable < 0.1! We start observations at 23:30 UT.

• Start a sequence on ngc1333S using Uranus as a calibrator. Uranus is at 40deg El at start. Done. Problem with scan 4 on Tue 20/01/26 (pointing on Uranus).
• Moving to 3c273 to focus and start a sequence on ngc2264D (the last one). During focus scan 13 was not processed. No output for the focus. Ran another pointing to check the beam size at ar1. the data are not processed. Error "Corrupted file or synchro problem or..." it got stuck on scan 9 (part of focus). Problems continue most probably because of wind error message "Corrupted file, 29.5% records with too high tracking dev.and/or incorrect slow antenna traces, CANNOT PROCESS"
• @2:13 UT Gloria parks the telescope due to strong wind.

Tuesday, 20th January 2026

03:00-09:30 UT Stefano:

• telescope parked for wind and clouds.
• Northern lights seen from NOEMA @22-23 UT of Jan 19th!!! AAAHHHH!
• @7:30 UT the wind is below 18 m/s since 45 minutes. The forecast says that it should slightly decrease. We try to see if keeping the telescope observing in the opposite direction than where the wind comes from, might work again like yesterday.
• switch to total power. Lost KIDs: 28/6/34
• PIIC monitor on pointing: 6.9% of records with too high tracking deviations. On focus sequence (5 scans, nr 19 to 24): 19.4%, OK, 16.6%, 20.9% (not processing), 20.9% (not processing).
• The telescope needs to be parked again. Well, we tried.

End of the pool week. A big that you to all participants for the help and the great time together. Stefano.