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Service observations with ISIS
ISIS offers a wide variety of observing setups, as it allows the user to choose the central wavelengths, slit width, dichroic, on-chip binning, etc. In order to minimize the time invested on setup changes and acquisition of calibration frames during service observations, the number of setups offered is limited. Nevertheless, non-default settings are allowed if their need is scientifically justified in the service application. Any corresponding additional overheads for the change of setup on sky, will be accounted to the requesting programme.
Having a large database of observations using a limited set of ISIS setups will also allow us to keep an optimal quality control of the instrument that will benefit users.
Imaging polarimetry, and observations requiring the QUCAM CCDs, are excluded from ISIS service observing, because of the higher cost and more limited opportunities to carry out such observations.
Spectropolarimetry observations, however, can be requested. They will be attempted whenever (1) a spectropolarimetry-trained observer is scheduled and (2) there is enough time to carry out the (extended) day-time set-up. The latter condition may not be satisfied e.g. on winter service nights (S, S/D) when ISIS has just been mounted on the telescope. The probability of completing spectropolarimetry proposals is therefore not as high as for normal ISIS service proposals.
2. ISIS default settings
The following settings are the default for service observations:
Exceptions to these default settings will be considered if justified in the service proposal.
The two tables below list the gratings and central wavelengths offered during service nights, along with spectral dispersions and wavelength ranges. Notice that the response of the system+dichroic should also be taken into account (wavelength ranges in parentheses).
Basic calibrations (biases, tungsten flats and CuNeAr arcs) will be obtained by default in the afternoon/morning for each observing setup used during the service night. Other calibrations (flux standard, radial velocity standard, solar analogue stars, etc.) should be clearly described by the PI in the service proposal, who should also provide name, coordinates, finder chart, and any particular observing conditions. These extra calibrations, and any other calibrations (arcs, lamp flats) necessary to obtain while observing, will be charged to the total time requested.
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