This note presents a baseline design for the CoSMO Prominence and Filament Magnetometer. It discusses objectives, requirements, design, and predicted performance. The baseline design is a full disc achromatic refracting coronagraph polarimeter that can operate at Helium D3, Hydrogen, and Helium-I... Show moreThis note presents a baseline design for the CoSMO Prominence and Filament Magnetometer. It discusses objectives, requirements, design, and predicted performance. The baseline design is a full disc achromatic refracting coronagraph polarimeter that can operate at Helium D3, Hydrogen, and Helium-I 1083nm. A proposed name is Chromospheric Magnetometer or ChroMag. Until there is general approval this document will use the name Prominence Magnetometer. Show less