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22:00-03:00; Ioannis, Frédéric: [IM: We start at 22:00, after maintenance and the technical time slot T06-21 that was dedicated to measurements for the telescope efficiencies. Initial NIKA2 tuning looks fine with 29/7/50 bad KIDs for A1/A2/A3, respectively. However, initial pointing and focus yields a strange effect only for 1mm data: 4 images of the pointing source in a cross-like pattern. This was not visible for 2mm data. We repeat the pointing to another source and get the same effect. Then we try to re-start everything: put mirrors back to EMIR setup and then back to NIKA2 setup and restart DAQ and retune KIDs. After these steps the pattern at 1mm data goes away. We have good beam size and shape (~17.7" @ 2mm and ~12" @ 1mm) as well as atmospheric fluctuations are very low (~0.5 Jy/beam). After a calib_1scan [20220301s246] and a beam map [20220301s247] on the quasar 0316+413, we start with observations for the IMEGIN LP (160-16).] 22:00-03:00; Frédéric (on-site) & Hélène (remote): [IM: We start at 22:00, after maintenance and the technical time slot T06-21 that was dedicated to measurements for the telescope efficiencies. Initial NIKA2 tuning looks fine with 29/7/50 bad KIDs for A1/A2/A3, respectively. However, initial pointing and focus yields a strange effect only for 1mm data: 4 images of the pointing source in a cross-like pattern. This was not visible for 2mm data. We repeat the pointing to another source and get the same effect. Then we try to re-start everything: put mirrors back to EMIR setup and then back to NIKA2 setup and restart DAQ and retune KIDs. After these steps the pattern at 1mm data goes away. We have good beam size and shape (~17.7" @ 2mm and ~12" @ 1mm) as well as atmospheric fluctuations are very low (~0.5 Jy/beam). After a calib_1scan [20220301s246] and a beam map [20220301s247] on the quasar 0316+413, we start with observations for the IMEGIN LP (160-16).] Earlier that evening the staff performed some tests to characterize the efficiency of the telescope. The AoD started tuning NIKA2 around 22:05. After a series of calibrations, we realized that the 1mm beam was shaped as a quadrupod (two images in azimut, two images in elevation), although the 2mm beam was perfectly normal. The operator went to change the configuration several times and the AOD retuned NIKA2, until the problem disappeared. A beammap was launched on 0316+413 at 23:40 after a calib_1scan. We started observing project 160-16 at 00:30. We stayed the whole shift on NGC4321 (@60"/s; 9 complete scans in total; 124 minutes on source), but were blocked in the middle of scan 20220302s13 without noticing, and for an unknown reason. An alarm was triggered, but nobody realized its cause. The elevation was less than 70 degrees, so the scan speed should not have been a problem. We calibrated on 1226+033 (pointing and focus) at 00:10 and 02:03. The focus changed from -0.35 mm to -0.60 mm in 3 hours. The opacity was very stable at 0.10 to 0.11 for the whole shift, and the sky rms at 2mm was between 0.5 and 1 Jy/beam. Too bad a lot of time was lost in such a fantastic weather!

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Daily Reports

Mar 1st, Tuesday

22:00-03:00; Frédéric (on-site) & Hélène (remote): [IM: We start at 22:00, after maintenance and the technical time slot T06-21 that was dedicated to measurements for the telescope efficiencies. Initial NIKA2 tuning looks fine with 29/7/50 bad KIDs for A1/A2/A3, respectively. However, initial pointing and focus yields a strange effect only for 1mm data: 4 images of the pointing source in a cross-like pattern. This was not visible for 2mm data. We repeat the pointing to another source and get the same effect. Then we try to re-start everything: put mirrors back to EMIR setup and then back to NIKA2 setup and restart DAQ and retune KIDs. After these steps the pattern at 1mm data goes away. We have good beam size and shape (~17.7" @ 2mm and ~12" @ 1mm) as well as atmospheric fluctuations are very low (~0.5 Jy/beam). After a calib_1scan [20220301s246] and a beam map [20220301s247] on the quasar 0316+413, we start with observations for the IMEGIN LP (160-16).] Earlier that evening the staff performed some tests to characterize the efficiency of the telescope. The AoD started tuning NIKA2 around 22:05. After a series of calibrations, we realized that the 1mm beam was shaped as a quadrupod (two images in azimut, two images in elevation), although the 2mm beam was perfectly normal. The operator went to change the configuration several times and the AOD retuned NIKA2, until the problem disappeared. A beammap was launched on 0316+413 at 23:40 after a calib_1scan. We started observing project 160-16 at 00:30. We stayed the whole shift on NGC4321 (@60"/s; 9 complete scans in total; 124 minutes on source), but were blocked in the middle of scan 20220302s13 without noticing, and for an unknown reason. An alarm was triggered, but nobody realized its cause. The elevation was less than 70 degrees, so the scan speed should not have been a problem. We calibrated on 1226+033 (pointing and focus) at 00:10 and 02:03. The focus changed from -0.35 mm to -0.60 mm in 3 hours. The opacity was very stable at 0.10 to 0.11 for the whole shift, and the sky rms at 2mm was between 0.5 and 1 Jy/beam. Too bad a lot of time was lost in such a fantastic weather!

Here is an example with the strange effect at 1mm data. Both plots correspond to the same scan (20220301s241), one for Ar1 and the other for Ar2:

attachment:20220301s241_Ar1.png attachment:20220301s241_Ar2.png

RZ, 2022.03.02 9:49

1. the beam of ar2 is not affected => problem is only of the 1mm arrays => not the mirrors

2. the source is shifted only in the scanning direction: in az in the focus maps, in az&el in pointings => synchro problems of the 1mm arrays

the angular distance btw. the shifted sources + the scanning velocity allow to calculate the synchro. time error, from the pointings: ~25"/(2*25"/s)=0.5s

Mar 2nd, Wednesday

03:00-05:00; Miren: Took over at 2h UT with tau255 ~ 0.125. Starting with pointing. Less than +/- 1 Jy/beam fluctuations and 17.4’’ FWHM beam @2mm. Project 199-16: one repetition on PSZ2G081 (40.5/44) and a repetition on PSZ2G046 (17.5/20). Pointing and focus, followed by a skydip (20220302s32). Sky fluctuations +/- 5 Jy/beam @ 2mm and tau225 ~ 0.15, 17.75’’ FWHM beam @2mm. Another repetition on PSZ2G046 (18.5/20). Ioannis takes over at 4h15 UT.

05:00-10:30; Ioannis: EMIR polarization observations with the POLAMI LP (087-21)

10:30-15:00; Philippe:

Mar 3rd, Thursday

Mar 4th, Friday

Mar 5th, Saturday

Mar 6th, Sunday

Mar 7th, Monday

Mar 8th, Tuesday

DailyReportsNika2Pool010322 (last edited 2022-03-09 13:44:32 by NikaBolometer)