The Narrow Field Imager (NFI) for the Polarimeter to Unify the Corona and Heliosphere (PUNCH): Instrument integration and status

The Narrow Field Imager (NFI) is a compact coronagraph designed and built by the US Naval Research Laboratory for the Polarimeter to Unify the Corona and Heliosphere (PUNCH) mission. The NFI coronagraph provides the inner part of the integrated PUNCH field of view from 6 to 30 Rsun. NFI will be mounted on a single spacecraft in the PUNCH constellation and provides high resolution 4 min observations. To provide superior observations of the corona within the limited volume and mass resources of the PUNCH micro satellites, we exploit the STEREO/COR2 heritage with the compact coronagraph design developed for the NOAA CCOR instruments. We present the NFI design, development, integration, testing and current status.