Is the Cometary Nucleus-extraction Technique Reliable?

Abstract

We investigated the reliability of the cometary nucleus-extraction technique, and found the answer to this question: it depends. Our experiment reveals that, given an optically thin coma, generally, the smaller the signal ratio of nucleus to coma, the less reliable the cometary nucleus-extraction technique is. We strongly suggest the technique only be applied to cases where the nucleus signal occupies ≳10% of the total signal wherein the bias is no more than a few percent. Otherwise, there is probably no way to debias results from this technique in reality, as its reliability is highly sensitive to entangling complications, including the coma profile, and the point-spread function (PSF).