The High-Resolution Coronal Imager, Flight 2.1

TL;DR

The Hi-C 2.1 mission successfully captured high-resolution images of the solar corona, providing valuable data on coronal features and their dynamics through a modified instrument with enhanced imaging capabilities.

Contribution

This paper presents the design, modifications, and observational data of the Hi-C 2.1 instrument during its third flight, offering improved resolution and coordinated multi-instrument observations.

Findings

Resolved coronal features at 0.47 arcsec resolution.

Captured 78 images over 5 minutes with 4.4 sec cadence.

Provided unprecedented data on chromosphere-corona coupling.

Abstract

The third flight of the High-Resolution Coronal Imager (Hi-C 2.1) occurred on May 29, 2018, the Sounding Rocket was launched from White Sands Missile Range in New Mexico. The instrument has been modified from its original configuration (Hi-C 1) to observe the solar corona in a passband that peaks near 172 Angstrom and uses a new, custom-built low-noise camera. The instrument targeted Active Region 12712, and captured 78 images at a cadence of 4.4 sec (18:56:22 - 19:01:57 UT; 5 min and 35 sec observing time). The image spatial resolution varies due to quasi-periodic motion blur from the rocket; sharp images contain resolved features of at least 0.47 arcsec. There are coordinated observations from multiple ground- and space-based telescopes providing an unprecedented opportunity to observe the mass and energy coupling between the chromosphere and the corona. Details of the instrument and the data set are presented in this paper.