Whitepaper #032 in the Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033. Main topics: basic research; infrastructure/workforce/other programmatic. Additional topics: solar physics; space-based missions/projects; research tools and infrastructure.
Visible and near-infrared (V+NIR) coronal emission lines have proven diagnostic potential for probing the physics of the middle corona from 1.5 to 6 Rs. Current ground- and space-based coronagraphs are not able to explore this region. There is a dire need for new space-based assets to measure a wide range of V+NIR emission lines beyond 1.5 Rs with both spectrometers and narrowband imagers.