Day to day observation logbook
link to summary table with plots |
X hours observed / X hours scheduled |
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link to summary table with plots |
X hours observed / X hours scheduled |
|
link to summary table with plots |
X hours observed / X hours scheduled |
|
link to summary table with plots |
X hours observed / X hours scheduled |
Quick summary of observations per day
Tuesday 7th
The beginning was a bit tough because Elvin considered we were GISMO where as all initializations were correct from the control room point of view. Juan Macias managed to twist our code to circumvent this and we could start observing. It took us then some time to tune the dectectors and retest the Real time analysis sequences. At some point, when we stopped the HWP, we lost the resonances at 1mm. In the last couple of hours, we installed the prism to have a first go with this kind of data.
Wednesday 8th
It was one of these nights... At the beginning, we were not seeing anything because M4 was not fixed properly. Then we had a hard time debug the our pointing code. In addition, the weather was not very nice, high opacity and rising, wind... making focus track also hard to get. We eventually tried our otf geometry on Uranus (not up in the sky at the beginning of the session) and found a very strong systematic effect while the HWP was rotating. Then we alternated between problems with the sky, the wind, extra noise with the HWP. We put and removed the polarizer, put and removed the prism to see how much the it blocked this systematic and reflect/absorb the signal. By a quicklook at the measured Uranus flux and previous knowledge by Andrea, Alain and Samuel, we confirm that the prism reflects about 25% each face and absorbs about 25% too (=> ~40% global transmission). In the end, the MPPSync crashed so the HWP coult not be rotated any more.
Thursday 9th
We've worked on fixing the MPPSync, and we start our observing session, Alain is in the cabin trying to replug and relaunch it. It's been fixed but we've had problems with the resonnances and the tuning all night, and bad weather. Lots of tests were performed on the instrument but few observations are available in the end.
Friday 10th
Soft: The tuning and acquisition worked fine again so we could carry out polarization observations during most of the night. However, there are a lot of gaps in the data (most likely due to missing antenna info, maybe because the acquisition is too ressource-consuming) that prevented us from analyzing the data in live. We solved the issue we had with pointing offsets not being correctly interpreted in the pipeline reduction: this was due to Nasmyth offsets not being properly implemented. Weather: - The wind prevented us from observing some sources that were located in directions were the wind would affect the antenna motors. - The PWV was not great (between 0.5 and 0.7) but we could still do some bright sources Polarized sources observed: - we tried to follow as much as possible BLLAC (about 6-8 maps taken with teh HWP rotating, at elevations ranging from 70 to 25 degrees). - NGC7538 3x3' maps obtained: 11 coverages with HWP rotating, 2 coverages without HWP rotating for comparison. - Cas A tentative map focusing on the brightest millimeter emission west of Cas A (23:23:15 +58:48:42.8). 4 coverages of a map that should cover 2x2' around this point. Script written quickly late in the night: to check