The Gemini Infrared Multi-Object Spectrograph (GIRMOS) is an adaptive optics-fed multi-object integral field spectrograph with a parallel imaging capability. GIRMOS implements multi-object adaptive optics (MOAO) for each of its spectrographs by taking advantage of the infrastructure offered by Gemini’s upcoming wide-field AO facility at Maunakea. The instrument offers the ability to observe four objects simultaneously at high angular resolution with MOAO within the Gemini-North AO (GNAO) system's 2’x2’ field-of-regard, or a single object within a narrow field corrected by laser tomographic AO (LTAO) and tiling the four fields that feed light to four separate spectrographs. Each integral field spectrograph has an independent set of selectable spatial scales (0.025", 0.05", and 0.1" /spaxel) and spectral resolution (R~3,000 and 8,000) within an operating band of 0.95-2.4µm. These spatial scales correspond to individual spectrograph fields of view of 1”x1", 2”x2" , and 4”x4", respectively. GIRMOS's imager offers Nyquist sampling of the diffraction limit in H-band over a 85”x85" imaging field. The imager can function in a parallel data acquisition mode with just minor vignetting spectroscopic pick-offs when they are deployed.
GIRMOS will enable targeting of high-redshift (1 < z < 10) galaxies in order to study their formation and evolution, back to a time in the early universe when galaxies were first forming. This also includes the investigation of galaxy mergers in dense environments at z~1-2. Additionally, we expect with GIRMOS to be able to carry out near-field cosmology through the study of metal-poor stars in the Milky Way Galaxy’s central bulge, as well as empower astronomers in the study of star formation physics within the Milky Way.
The project is being led by the University of Toronto (UofT) Dunlap’s Prof. Suresh Sivanandam, and is being funded through a Canadian Foundation for Innovation award of $5.2 million, with $8.7 million from provincial and other partners. The official project kick-off was in December 2018.
Major GIRMOS partners include:
Project Management: UofT.
Object Selection System: NRC.
Adaptive Optics: UBC, NRC, Dalhousie University, University of Victoria.
Spectrographs: UofT; Université Laval.
Software: Saint Mary’s University; NRC.
Additional partners include York University.
Gemini is presently funding the preliminary design study of the GIRMOS imager subsystem, providing in-kind staffing in overall project systems engineering, and other general support.