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Daily Reports

Contents

Daily Reports

Bilal, Charlene, Caroline, Iacopo, Florian, Stefano, Carsten arrive at the 30m. Full house.

Four shifts this time:
Afternoon (12:00-18:00 CET): Charlene and Caroline
Evening (18:00-00:00 CET): Bilal
Night (00:00-6:00 CET): Florian and Iacopo
Morning (6:00-12:00 CET): Carsten and Stefano

Last week, as NIKA2 was cold already, a frequency sweep was done at 1mm, and the pulse tube had been realigned by JLS, after notification by Martino who had seen indications of a spike at 0.3Hz.

Jan 14, Tuesday

Maintenance and afternoon/evening shifts

Laser used to check alignment between elevation axis and cryostat window. Strangely enough this seems to depend slightly on elevation. Small correction applied to M5 by SN.
Starting at 14:30 UT. High overcast of ice clouds.
Pointing session with ~33 sources (scans 237-269). Pointing offsets look OK. JP fits model. Fit of Nasmyth offsets leads to a very slight improvement from 1.9" rms to 1.7" rms. Not yet implemented. Beam widths look OK.
Secondary calibrators MWC349, NGC7027, CRL2688. Fluxes look OK.
Skydip
Beam map on Uranus at 50deg Elevation.
Central pixel lost. Hole in the 2mm array. Re-do tuning. Re-do pointing, focus, 2 beam maps to create new RPPs/kidpars after 1mm sweep done last week (scans 292 and 293).
tau225~0.14 and very stable. Forecast is good for the next two days. Ready to go. It would be helpful to have beam maps IMBfits be created separately from pointing and focus scans.
18:10 Finally, after 3.5 hours, starting with science: NIKA2SZ. New pointing model implemented in-between scans.

Night shift

Alternating NIKA2SZ and N2CLS COSMOS, with some observations of 128-19 and 126-19 too. Tau very stable, slowly degrading.

Jan 15, Wednesday

What a day!

Morning shift

Continuing with N2CLS GOODS-North. Pointing, focus, tau stable. tau225=0.2 @ 05:30 UT.
8:00 UT: Juan lets us know that the pulse tube has been re-aligned. Santiago confirms via email and explains the details: a 0.3 Hz spike was found remotely by Martino (Jan 9th) and Juan Louis at the telescope re-aligned the pulse tube.
At 9:00 UT Martino writes an email and lets us know that: " the levels of the cryostat (i.e. its position wrt to the floor) are not well in line with the 'reference' values. This is due to the fact that the cryostat is in a 'manual' state: no checks are done on it and no pressure adjustments in the pressure of the NIKA2 pneumatic feet are done. The state should be changed to 'level attente'. But.. This will move a little bit the cryostat! (...) For the time being, I don't touch anything, but in my opinion it would be better to go back to the standard operatin mode (level attente)." Comment by SB: At the moment, the pointing is quite stable and the sky is good too. Yesterday the mirrors were re-aligned and a new pointing model was done. I guess that if the cryostat is moved (by setting the leveling to "automatic"), then a new re-alignment will be necessary and shall be done. And a new pointing model too. Is it necessary right now, or can we wait the end of the run?
The operator (Ignazio) tries to start the cryostat monitor here but the connection does not work. Santiago will work it out later (he's now in a meeting). Yesterday it was on, as far as Ignazio remembers. Bilal confirms.
After some interaction with Martino, Santiago, Miguel, we decide to postpone switching to the automatic leveling of the cryostat to next Tuesday (end of the run), unless big pointing problems arise.
Meanwhile the connection to the cryostat monitor is re-established here too.
at 10:45 UT, synchronization problems between Boxes A and M/N/T (scan 81 of today) are reported by Nicolas via Juan and Martino. He used the IDL RTA. We cannot check with the PIIC monitor right now, because the RPPS for the new sweep are currently on the make by Stefano (who had some interruptions meanwhile, sorry). We reboot the electronic boxes after scan 92.

Afternoon shift

After the reboot, we observe project 143-19
At 12:10 UT connection was lost to the cryostat control machine. Valves closed automatically. The problem was realized around 12:50 UT. NIKA2 warmed-up to 500mK, when control was regained. Observations are stopped until operating temperature is reached again and is stablized.
At ~13:45 UT, and 0.178 K, the tuning is again effective and we can start to observe again. The temperature will decrease further, down to ~0.17. THe observer is asked if she is willing to continue the observations in these conditions. The observations of project 143-19 are resumed when the mixing chamber reaches a temperature of 0.171 K.
The amps and the temp regulation has been switched on at ~14:45 CET by Dave
In total 4 sources of 143-19 (two before and two after the temperature "break")
After some struggling to find the proper focus (it's afternoon after all), we switch to project 160-16. Two more scans on ngc891 (tau225~0.15 and stable).
When scans are long, the make-imbfits has delays. It would be nice to produce imb-fits of large scans in parallel, without slowing down the short ones (e.g. pointing and focus taken between or after long scans).

Evening shift

We observe project 160-16, 128-19, 163-19.