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Issue 1.3
LUCIFER User Manual
(a) rotation angle and telescope pointing in the upper left corner,
(b) position of the six reference slits
(c) calculated wavelengths limits on the array at the two southern corners
(d) central wavelength at the northern edges of the unclipped area
4. when adding guide stars: the guider patrol field.
Figure 11: Typical display of the LMS tool.
To make sure that the slits are on the sources when observing, the following rules have to be obeyed:
1. The FITS image must be distortion corrected with high accuracy and the plate scale has to be
known with high accuracy, catalog positions must have high astrometric accuracy.
2. Science sources and reference stars have to be taken from the same image or catalog. Their
relative positions have to be known to better than 1/6 of the slit width; otherwise slit losses
occur.
3. At least two reference stars have to be defined within the LUCIFER field to compensate for
pointing and image rotation offsets. Five reference stars are recommended for higher accuracy.
The maximum number of reference stars has been set to ten.
4. It is strongly recommended to limit yourself to a maximum of 40 slits per mask.
Slits are generated with the default settings for type, length and width. Changing the default settings
will affect newly created slits as well as already existing ones. Slits can be modified and deleted
individually by clicking on their number and width labels. When all slits have been positioned, the
setup can be saved. During this process, four files are generated:
1. a *.lms file containing the instrument parameters, all slit, reference star, and guide star positions
as well as all slit parameters. This file can be loaded again to restore the session,