DeepSpec: a Broad-band R ∼ 650 Spectrograph with Multiplexing Capabilities

DeepSpec is a novel R ∼ 650 broad-band (365nm-900nm) spectrograph for the Weizmann Multi-Aperture Spectroscopic Telescope (MAST), an array of 20 × 61 cm prime focus telescopes dedicated for spectroscopic observations, at the Weizmann astronomical observatory in Israel. MAST/DeepSpec is capable of either acting as a single 2.7m telescope or multiplexing over the entire sky using smaller flexible groups. This approach will make the combination of MAST/DeepSpec a unique facility worldwide in terms of its low cost, flexibility, and efficiency, capable of observing up to hundreds of targets per night spread over large areas. With an end-to-end throughput of > 65%, DeepSpec will be able to observe targets fainter than 20 mag in a 15-min exposure using all telescopes, or tens/hundreds of spectra per hour of 18-19 magnitude targets using smaller groups of telescopes - making it an ideal instrument for time-domain astronomy. All optics and hardware have been delivered during fall 2023 and DeepSpec is currently in the assembly, integration, and testing phase. It is planned to start on-sky commissioning in late summer 2024.