Staring at stars makes you see spots: verifying images of red supergiant stars

As some of the largest stars in diameter, red supergiants (RSGs) are ideal targets for interferometric imaging. In the past few years, studies have begun to shed light on the evolution of the surfaces and atmospheres of these stars, which deviate from centrosymmetry. In particular, RSGs have large granulation features which vary on timescales on the order of hundreds of days. In order to study these features and their evolution, we have undertaken a long-term imaging survey of RSGs using MIRC on the CHARA Array. We are seeking the highest resolution images of RSGs possible with CHARA, looking for variations of features less than half the size of the stellar surface. Here we present a method for determining the best method for reconstruction in order to minimize the impact of artifacts.

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