AIROPA III: Testing Simulated and On-Sky Data

TL;DR

This paper evaluates AIROPA, a software for analyzing adaptive optics images, demonstrating its effectiveness in modeling static aberrations but highlighting limitations in on-sky accuracy improvements due to uncalibrated telescope aberrations.

Contribution

The paper presents the testing of AIROPA on simulated and real data, showing its reliability in static aberration correction and identifying challenges in on-sky application.

Findings

AIROPA effectively models static internal aberrations.

Limited improvement in on-sky accuracy due to uncalibrated telescope aberrations.

Reliable in simulated data but faces challenges with real observations.

Abstract

Adaptive optics images from the W. M. Keck Observatory have delivered numerous influential scientific results, including detection of multi-system asteroids, the supermassive black hole at the center of the Milky Way, and directly imaged exoplanets. Specifically, the precise and accurate astrometry these images yield was used to measure the mass of the supermassive black hole using orbits of the surrounding star cluster. Despite these successes, one of the major obstacles to improved astrometric measurements is the spatial and temporal variability of the point-spread function delivered by the instruments. AIROPA is a software package for the astrometric and photometric analysis of adaptive optics images using point-spread function fitting together with the technique of point-spread function reconstruction. In adaptive optics point-spread function reconstruction, the knowledge of the instrument performance and of the atmospheric turbulence is used to predict the long-exposure point-spread function of an observation. In this paper we present the results of our tests using AIROPA on both simulated and on-sky images of the Galactic Center. We find that our method is very reliable in accounting for the static aberrations internal to the instrument, but it does not improve significantly the accuracy on sky, possibly due to uncalibrated telescope aberrations.