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Dark current measurements and hot pixels monitoring:

Dark current measurements and hot pixels monitoring. The script to be used is here. It takes about 1h to run the script.

Gain and linearity monitoring:

Gain calibration and linearity calibration. Exact procedure still to be written.

Zero points monitoring:

Measure standards stars during photometric nights to monitor the photometric zero points, or equivalently the throughput of the instrument in imaging mode.

Check Grism alignment and spectral distortion:

Measure a bright star at different positions along the slit. The trace of the spectra should be aligned with the detector rows close to the slit centre. These measurements are also useful to determine the curvature of the spectral traces along the slit length and correct spectral distortion when observing extended targets. The script which moves the target along the slit can be found here.

Measurement of local background:

The goal of this test is to monitor possible variations of the local sky background emission due to changes in the telescope environment. Select imaging mode and point to a standard photometric field close to the zenith. Perfom a sequence of short exposures at different airmasses. The background must increase with airmass, the extrapolation to zero airmass should give the local background.
The measurement should be done during a photometric night in order to have a proper calibration. The priority is filter Ks, although J and H should be done from time to time.