top Introduction

This tutorial provides information for the the Detector: monitoring Health Check trending.
The Detector: monitoring trending is based on the measurement of QC1 parameters of Detector Linearity calibration data obtained with a dedicated Health Check OB executed approximately monthly.
The Detector Linearity OB consits of 10 sets of data - each set is one DARK and two Imaging FLAT FIELD frames taken with the same DIT. The DIT is gradulally increased from set to set to increase the flat flux level

The data are obtained with the Ks filter using the Nasmyth shutter as a source: its flux is then dependent on the ambient temperature as expected from the Planck law.

As of 2016-09-28 only the effective linearity is monitored. The conversion factor (conad/gain) measurements were found unreliable. The corresponding HC plot was taken off-line untill template and/or pipeline recipe are improved.