Instrument-specific features within the observation preparation software for LINC-NIRVANA

The LINC-NIRVANA (LN) Observation Preparation Software (LOPS) supports an observer during the complex process of preparing the observations for LINC-NIRVANA (LN). LN is a German-Italian beam combiner for the Large Binocular Telescope. The instrument exploits its full capability by means of Multi-Conjugated Adaptive Optics and an IR Fringe and Flexure Tracker. These sub-systems of the LN instrument and the fixed geometry of the telescope put specific constraints on the observation and scheduling process. LOPS is committed to a generic approach which allows to easily include new features on the so called procedure-plug-in level (low level). Considering specific aspects of the LN instrument the implementation on the generic procedure level is not adequate enough, because an user/observer needs to deal with a lot of instrument-specific parameters when preparing an observation program (OP). For this reason, LOPS provides a high-level application plug-in system which allows to maintain the features of an OP also as separate application in order to benefit from the more advanced GUI. In this paper we present the Guide Star Buffer concept as an exemplary feature-specific application in the framework of LOPS. It is dedicated to search, select and organize guide stars in the corresponding groups needed for LN observations