Back to the NIKA2 main page

Daily Reports

Feb 1st, Tuesday

16:00-21:00; Ioannis: During maintenance, SN worked with MC on the problem of Ar1 resonances that show peaks around 3 Hz, 6 Hz and 9 Hz. They identified the Ar1 synthesizer as the source of the problem (by swapping the Ar1 and Ar3 synthetizers) and then replaced the faulty synthesizer with the last spare one. The problem is not visible anymore in the traces. We start the NIKA2 tuning after maintenance at 16:30 but we have a problem with Ar3 resonances. We restart several times the acquisition but we cannot tune Ar3 most of the times. After investigating numerous factors with JLS and contacting SN, we suspect that the increased temperature in the receiver cabin (up to 24 ºC) may be causing these problems. We turn off the Ar3 synthesizer, restart the temperature control in the cabin and use a fan for additional cooling of the crates (mainly 3). Around 20:30 the temperature in the cabin drops around 20 ºC. We restart the acquisition and Ar3 behaves normally (bad kids: 43/7/48 for Ar1/Ar2/Ar3), so we start with the observations. After pointing on Uranus we stop at 21:15 due to high wind. Observations restart at 22:00. Pointing and focus on Uranus but the beam is a bit elongated (17"x20" at 2mm and 11"x14" at 1mm), most likely because the antenna temperature evolution shows that the cooling of the structure is slower than usual today (highest temperature peak in the last few weeks). Will have to wait a bit longer for the antenna to fully relax.

21:00-03:00; Guilaine: Exceptional tau (0.15) but very bad shift. Electronic problems at the beginning. Then windy. Start observing Uranus at 22:10. Series of pointing/focus. Beams way too bad (today was the hottest day since 1 month). Change source to the very bright 0316+413 (since Uranus at too low elevation). New series of pointing/focus. Skydip [20220201s158]. 23:28, beams of 12.13 – 17.92 – 12.29. Launch 1 repet on source NGC1333-C7 (18 minutes), which is very close to 0316+413. Then again series of pointing/focus. Although the focus was at expected value, very degraded beams. 1:06: do a "retune". And restarting the whole acquisition (too much bad KIDS in array1). 2:00: pointing scan on 0552+398. Beams of 12.78, 18.33, 12.90. Got to project 137-21 to observe a low priority target (WB89-640). Scan 14 aborted at 03:12 since array 3 was lost (lost before 03:05, I don’t know exactly when, cannot see the acquisition screen remotely; scan 12 reduced with nk_rta and doesn’t seem weird).

Feb 2nd, Wednesday

03:00-09:00; Juan: At the beginning of the shift array 3 showed problems again -operator went up to the cabin to restart and cool down the synthetizer. We finally manage to observe for 2 hours or so, 2.5 repetions on PSZ2G122

09:00-15:00; Ioannis: At 09:30 SN arrived at the telescope and we tried to resolve the issue with the Ar3 synthesizer. First we replaced it with the previous one but unfortunately didn't work. Then we tried the synthesizer used for VLBI and fortunately worked and Ar3 was stable again. PIs are noted that NIKA2 observations between scans 20220101s128 and 20220102s24 may be affected by the unstable behavior of Ar3 synthesizer and are advised to proceed with the data reduction with caution. After the replacement of the Ar3 synthesizer, we restart with NIKA2 observations around 11:00 (good tuning with 38/6/47 bad kids for Ar1/Ar2/A3), but unfortunately the beam is relatively large and elongated even after several focus attempts. We take this opportunity and do some polarization tests with NP, MC, JMP, AB, PA, DJ and AS, in view of the upcoming B-FUN observations this Friday. We made sure that HWP operated as expected, go through the steps required to prepare the acquisition software for polarimetric observations and make sure that the IDL pipeline (called by "idl_polar" for NIKA2-Pol) is able to reduce pointings, focus, skydips and science observations. IMBFITS are created for polarization data but the PIIC monitors are not analyzing them at the moment. The tests last until the weekly NIKA2 meeting at 15:00.

15:00-21:00; Isabelle & Aurore: [IM: We restart with NIKA2 observations at 16:00. However, the beam is still too large and elongated to start with the science observations (12"x20" for 1mm and 17"x22" for 2mm). The situation improves slightly around 17:00 and we do a calib_1scan on Uranus [20220102s113] and then a skydip [20220102s114]. At 17:30 the wind gets too high to continue (> 20 m/s) and we stop the antenna.] Stopped throughout the shift due to high wind.

21:00-03:00; Matthieu: The opacity was fantastic (tau~0.1) during the 9pm-3am shift. However, the wind (15-25 kms) decided otherwise.

Feb 3rd, Thursday

03:00-09:00; Corentin & Miren: Stopped throughout the shift due to high wind.

09:00-15:00; Ioannis: After a long pause due to high wind, we restart NIKA2 observations around 12:00. Good tuning with 34/5/45 bad kids for Ar1/Ar2/Ar3. Pointing and focus on 1633+382 with small and symmetrical beams in both bands. Then observations of L694 (2 repetitions) for project 109-21. Then we move to project 137-21 and observed 19383+2711 (second attempt because first time it was interrupted).

15:00-21:00; Isabelle & Aurore: Good weather conditions and stability, slightly distorted beams at the beginning, improving. Eight scans on L1521E from 15:30 UT to 18:50 UT. calib1scan [20220203s44] and skydip [20220203s45] performed at the beginning of the shift (15:20 UT). [IM: At 19:50 we performed EMIR observations for about 1.5 hrs, as requested by RN and CK].

21:00-03:00; Ioannis: Due to degrading weather, we continued with EMIR and observed for the backup project 170-21.

Feb 4th, Friday

03:00-09:00: Laurence: No NIKA2 observations due to poor weather; tau225 of about 0.6 (with variations from 0.55 to 1). [IM: EMIR observations until 08:00. Then stopped because the weather was too bad even for that.]

Feb 5th, Saturday

Feb 6th, Sunday

Feb 7th, Monday

Feb 8th, Tuesday