Detector

The NOTCam engineering grade array (SWIR1) has been sold to the NBI under a contract where we can borrow it back over a period of 2 months as a spare in case our science array needs replacement. This would still not be a longer term solution in case of problems, and as a precaution an informal quote for a replacement Hawaii 1k array was obtained from Teledyne. The availability was confirmed, and a price estimate of US$35000 was provided. However, it is not clear what quality array to expect. For this an official quote must be requested.

The so-called "reset level" is the count level of the pre-integration readout of the array. It is supposed to be a function of detector temperature. When commissioning the array, it was adjusted to an optimal level, i.e. a level that maximises the dynamical range and minimises bad pixels. Over the years we have experienced various jumps in this level, needing a re-adjustment of the DC-offset voltages each time.

The investigate this more, we need to monitor the array, but as this accumulates 1 GB of data every day, a script was made to analyse the images, store the results, and delete the data. The results still needs to be analysed in detail.

Thomas Augusteijn 2013-12-02