GeminiFocus 2015 Year in Review | Page 45

Figures 13-14. Top: A final mask design overlaid over a GMOS-S pre-image. The large green rectangle displays the detector area where spectra are recorded. The thick red polygon indicates the field-ofview within which slits (small yellow vertical bars) may be placed. The spectral footprints are shown as filled horizontal rectangles. Bottom: The user interface that controls which elements are shown in the pre-image display. It also shows the number of valid acquisition stars and issues warnings if spectra are truncated by the finite detector geometry. Mask-making Software Updated Multi-Object Spectroscopy (MOS) is in high demand at both Gemini telescopes. Principal Investigators individually design the MOS masks for each science program using the Gemini Mask Making Preparation Software (GMMPS). Once checked, the physical masks are precisely cut using a laser milling machine in Chile (shared between Gemini, Cerro-Tololo International Observatory, and the Southern Observatory for Astrophysical Research). January 2016 After the installation of the new red-sensitive Hamamatsu CCDs in GMOS-S, which have different geometries and pixel scales compared to the detectors in GMOS-N, we recognized that the GMMPS source code had significant shortcomings that prevented its use for creating masks for both GMOS instruments. In a concerted effort, the code was recently made less instrument-dependent. This fix also paves the way for mask creation for the MOS mode of the near-infrared Flamingos-2 instrument, commissioning of which will begin this year. At the same time, all user interfaces were 2015 Year in Review GeminiFocus 43