A Visible-light Lyot Coronagraph for SCExAO/VAMPIRES

TL;DR

This paper presents a new visible-light Lyot coronagraph designed for the SCExAO/VAMPIRES system, demonstrating initial on-sky performance with multiple mask sizes and promising contrast levels for high-contrast imaging.

Contribution

The paper introduces a novel four-mask Lyot coronagraph for visible light, with detailed design, deployment, and initial on-sky performance results.

Findings

Achieved contrast of 1e-2 at 0.1" and 1e-4 at 0.75"

Multiple masks with inner working angles from 36 mas to 129 mas

Coronagraph deployed in early 2022 and available for use

Abstract

We describe the design and initial results from a visible-light Lyot coronagraph for SCExAO/VAMPIRES. The coronagraph is comprised of four hard-edged, partially transmissive focal plane masks with inner working angles of 36 mas, 55 mas, 92 mas, and 129 mas, respectively. The Lyot stop is a reflective, undersized design with a geometric throughput of 65.7%. Our preliminary on-sky contrast is 1e-2 at 0.1" to 1e-4 at 0.75" for all mask sizes. The coronagraph was deployed in early 2022 and is available for open use.