Description
The Blue Multi-Unit Spectroscopic Explorer (BlueMUSE) is an integral field spectrograph intended for installation on one of the telescopes of the Very Large Telescope (VLT) of the European Southern Observatory (ESO) in the early 2030s. BlueMUSE is built on the heritage of MUSE and is a blue-optimised (350-580nm), panoramic integral-field-spectrograph with a minimum field of view of 1 arcmin2 and medium spectral resolution (R~3500).
Using a similar architecture to MUSE reduces risk, while extending the wavelength range down to 350nm, coupled with higher spectral resolution, enables new and complementary science cases. In Spring 2025, BlueMUSE successfully passed its Phase A review, marking the completion of the conceptual design. When built, the instrument will employ 16 identical integral field units (IFUs), each containing a dedicated spectrograph. Each spectrograph uses a volume-phase holographic grating (VPHG) as a dispersing element, and images the telescope field of view onto the detector. Here we present the conceptual optomechanical design of this spectrograph, which was developed by the Centre for Advanced Instrumentation (CfAI) of Durham University, and Lyon Centre for Astrophysics Research (CRAL).
