Extended Data Fig. 2: Keck Point Spread Function (PSF) fit and residuals.

(a) Keck/NIRC2 H-band image from 2018. (b) Residuals after fitting the PSF using multiple stars in the neighbourhood of the source. Both the object to the north-east (upper left in panel A) and the object at source position (lower right) are subtracted using this PSF fit. There is no structure or indication of a double star in either of the two objects. (c) The residuals from panel B normalized to the Poisson noise. (d) Panel A but subtracting the fitted PSF from the unrelated companion.