# Lessons learned from the NEAR experiment and prospects for the upcoming mid-IR HCI instruments

## TL;DR

This paper reviews lessons from the NEAR experiment on high-contrast imaging in the mid-infrared, highlighting the impact of water vapor on performance and discussing prospects for future instruments.

## Contribution

It provides an analysis of NEAR's performance limitations due to water vapor and offers insights for improving mid-IR high-contrast imaging instruments.

## Key findings

- PWV is the main contributor to thermal sky background in mid-IR HCI.
- High PWV degrades HCI performance significantly.
- NEAR can detect Jupiter-mass planets within hours.

## Abstract

The mid-infrared (IR) regime is well suited to directly detect the thermal signatures of exoplanets in our solar neighborhood. The NEAR experiment: demonstration of high-contrast imaging (HCI) capability at ten microns, can reach sub-mJy detection sensitivity in a few hours of observation time, which is sufficient to detect a few Jupiter mass planets in nearby systems. One of the big limitations for HCI in the mid-IR is thermal sky-background. In this work, we show that precipitate water vapor (PWV) is the principal contributor to thermal sky background and science PSF quality. In the presence of high PWV, the HCI performance is significantly degraded in the background limited regime.