GHOST System Verification Update

A successful GHOST System Verification (SV) run was conducted 10–18 May. The goals of the run were to: 1) perform full end-to-end testing of observatory software, documentation, and operational procedures, and 2) provide an initial set of publicly available GHOST data to showcase the commissioned capabilities and range of science and inform proposal preparation by the wider Gemini community. We allocated 40 hours of engineering time for these observations. 

Ahead of the run, 60 hours of observations were suggested by the Instrument Science Team, which readily filled the available time. A set of high-priority observations were chosen from this set in order to ensure that the 40 hours of observations would span a range of different science, cover all the commissioned GHOST modes and capabilities, and also be observable in a range of conditions. The GHOST SV webpage provides information on the science that was proposed and details the observations that were made. Seven SV programs were created and organized by science topics. These include: galactic metal-poor stars, transmission spectroscopy of hot exoplanets, white dwarfs and symbiotic stars, binary star systems, chemical abundances of ultra-faint dwarf Milky Way satellites, low-metallicity early-type stars in a Local Group dwarf irregular, and extragalactic compact stellar systems. High-priority observations for most of these programs were successfully completed along with some of the additional observations with the remaining time.

Raw data from these programs will become public and accessible in the Gemini Archive after one month. We expect that in two months, the evaluation of these data will be presented on the webpage, and are planning for webinars in August to help better prepare the community for the first open proposal call later this year. This first Call for Proposals for GHOST will be in Shared Risk mode, and is expected in late August for observations in the period November 2023 – January 2024. 61.3 hours have been allocated for the Shared Risk observations. It is expected that most modes of GHOST will enter routine science operations in 24A and available through the regular calls for proposals.