Mauna Kea Spectrographic Explorer (MSE): new preliminary design for the multi-object high resolution spectrograph

The Maunakea Spectroscopic Explorer (MSE) project will transform the CFHT 3.6m optical telescope to an 11.25 m multi- object spectroscopic facility with an ability to simultaneously detect thousands of objects with three spectral resolution modes, low resolution of R ~ 3,000, moderate resolution of R ~ 5,000, and high resolution of R 20,000 ~ 40,000, respectively. The multi-object high resolution (HR) spectrographs can derive simultaneously around one thousand high- resolution spectra of Blue, Green, and Red channels, respectively. Based on the discussion of the science cases in 2019, the design team suggested that the optimal design of HR spectrograph should balance between the new scientific requirements and technical feasibility. Here, the HR design team shows the trade-off study's progress and introduces a new preliminary design.