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Daily Reports (2025/12/9-16, NIKA2 run 77, Cryo run 89)

Observers on-site: Simon, Yiqing, Monica, Philippe (in remote first 2 days)

Astronomer-of-Duty, Pool Manager: Angel Bongiovanni

Operators: Joaquin, Pedro

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

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

Pool-Account usage: Accounting of observing times

December 9th, 2025, Tuesday

16:00 - 22.00 Monica: We started the observations , tau ~ 0.25 a bit unstable, no wind, very high clouds. DAQ started in total power. Bad kids (Ar1, Ar2, Ar3 / 8, 7, 29). After pointing and Focus calib_1scan in MWC349 (Scan 20251209s128) and NGC7027 (s130). Then skydip (s131). Then we move to project 152-25 (Science source WB89-152 ~ 70 min -DONE). Pointing & Focus & calib_1scan (s163) in Neptune. At 19:50 we move to polarimetry projects. New DAQ, bad kids (Ar1, Ar2, Ar3 / 17, 7, 39). Then move to project 170-25. Calib_1scan (s165). Continue with the science source (Tycho - 1 rep). Calib_1scan in Neptune. move to nikaw-25 Pointing & focus & calib_1scan in Uranus.

22:00-24:00 Philippe (Remotely from Granada office): Observed a polarized focus sequence on Neptune (s199-s204) and a polarized calib_1scan on Neptune (s205), but opacity and stability were degrading, therefore switched to TP. New DAQ, bad kids (Ar1, Ar2, Ar3 / 28, 7, 73).

December 10th, 2025, Wednesday

00:00-04:00 Philippe (Remotely from Granada office): Did 1 calib_1scan on Uranus (s209) and 1 skydip (s210) in TP. Then switched to EMIR, project 147-25. Checked reference position: neither N2H+, nor SO emission in reference position; no significant C18O emission emission either, but probably weak C18O in the off position; there is definitely 13CO, HCO+, and HNC emission in the off position used to observe the reference position in position switching --> Consider observing the reference position in frequency switching? Observed the two positions p1oh (s222) and p2oh (s2) used for internal calibration purposes, then took one pair of OTF maps (@147-25_W3OH_OTF_scX + 147-25_W3OH_OTF_scY) and started another pair (@147-25_W3OH_OTF_scX).

04:00-10:00: Simon: Important spikes on tau-meter with tau~0.38 and a wind of ~9-11 m/s, high clouds. Completed the second repetition of latest map (@147-25_W3OH_OTF_scY) after pointing and focus. Observed negative features around 88 GHz (scans 24 and 32). The VESPA data appears to have important oscillations on vertical polarization (VESPA-2). The operators know. At 05:00 considered the project as closed for tonight. We change to project 193-25 of the EMIR Backup programmes at 05:20. tau~0.35 and decreasing, wind speed of ~9 m/s and decreasing, high clouds. Pointing and focus to 1226+023 were successful but we detected an anomaly possibly affecting a subscan of the correlator on WILMA-4 that could affect science target for 12CO(2-1) line. FTS spectra are okay. Scans 60 and 61 show artifacts above 89.6 GHz (already reported by the operator to GP); they do not appear in following scans after re-calibration. After repetition 12 (scan 84), we evaluated a possible switch to NIKA2. Although the tau is low (~0.35), the atmospheric conditions are looking bad (thick clouds coming from the North covering ~60% of the sky) and the opacity is increasing based on the predictions. So we decided to continue with project 193-25, using EMIR.

10:00 - 16:00 Yiqing: Tau~0.35 with unstable condition and overcast sky. Continue with observing with EMIR. We switch project to 149-25 using E150, tuning results on 1253-055 look ok. Move to project test to check the pointing and focus on 1253-055, results look reasonable. Attempts to point on 2037+511 near the science target failed due to worsening weather conditions. As no other backup projects are suitable, we attempt to point on a brighter source K3-50A, results look ok, proceed to point back on 2037+511, results ok, moving back to project 149-25. Pointing on 2037+511 yields bad results, meanwhile high wind with gust > 10km/s is destabilizing the telescope tracking. Telescope sent to stop at ~ UT12:20.

16:00 - 22:00 Monica: Snowfall, high wind speed. Telescope stopped until ~19h (LT). Opacity ~0.5, wind speed between 7 and 10 m/s. Resuming observations with EMIR backup programs (project 149-25). Switching to project test. Unstable atmosphere. Tried several pointing corrections after focusing (EMIR E1: 140.1 GHz). Constant evidence of anomalous refraction. Instabilities increase. Parking the telescope at 21:10 (LT).

22:00-24:00 Philippe (remotely from Granada): Telescope parked in stow position. Light hail. Cloudy.

December 11th, 2025, Thursday

00:00-04:00 Philippe (remotely from Granada): Telescope parked in stow position from start of shift until ~1:30 LT. Unstable atmosphere with high opacity ~ 0.4-0.5. Very light snow. Started observing again around 1:30 LT with EMIR project 147-25. Opacity tau225 ~ 0.35, but significant fluctuations (up to ~0.6) preventing NIKA2 observations. Used frequency switching to confirm that the adopted reference position is free of any significant HCO+ and HNC(1-0) emission down to < 0.05 K at FTS200 spectral resolution. Observed the two positions p1oh (s13) and p2oh (s15) used for internal calibration purposes. Then executed @147-25_W3main_OTF_scX (~1h30 script) once. Ended with observing the internal calibration position p1main (s30)

04:00-10:00 Simon: Continued with internal calibration position p2main (scan 32). Pointing shows signs of weak anomalous refraction, possibly due to opacity variations close to the telescope (snow cannon). Opacity tau~0.32, quite stable. Continuing with project 147-25. Wind rising up to 14 m/s (mean around 10 m/s) at 06:00. tau~0.3. At 06:00 we switched to project 193-25. Wind is rising (max speed 20 m/s) and tau decreasing to 0.26. We switched to project test (scans 60 to 63) to get pointing and focus. Several attempts to get pointing and focus were unsuccessful, with unloaded scans and failed focus scan (scan 60). At 6:56 the telescope was stopped. Resume observations at 9:30. Switched to NIKA2. DAQ started in total power. Bad kids (Ar1, Ar2, Ar3 / 21, 5, 38). Wind speed around ~10 m/s, increasing, and tau~0.33 decreasing. Data loss of >30% due to high wind speed. Moved to other source to complete focus and pointing; this was successful.

10:00 - 16:00 Yiqing: Continue with project 197-25 with NIKA2. Started in nikaw-25 account for focus on 1641+399, results good, move to pointing source 1807+698, results ok. Switch to 197-25 account, repeat the pointing on 1807+698, results ok, started observing EDFN_CL1 with tau ~ 0.36. However, sky stability is marginal for the project, with peak to peak ~ 6Jy/beam, -- hence after 1 repetition we switch to observatory calibration to low-EL sources (MWC349, NGC7027, CRL2688, at ~ 30 -35 deg EL). For pointing on MWC349, we have high instability with peak to peak of > 50Jy/beam due to passing clouds. Stopped NIKA2 observation at 12:38 due to high instability, switching to EMIR project 123-25 with E90/FTS50. Telescope Az. brakes error, initial calibration done without sky after tuning, receiver temperature ok.

16:00 - 22:00 Monica: Az. brakes error under further investigation by the Telescope Group and Operators. Telescope safe in stow position. High wind speed. No observations since ~13h.

December 12th, 2025, Friday

High winds continue during the second half of the night. No observations.