Reddened Dimming of Boyajian's Star Supports Internal Storage of Its "Missing" Flux

TL;DR

This study shows that the dimming and reddening of Boyajian's Star are consistent with internal flux storage and cooling, challenging external obscuration hypotheses and providing new insights into its unusual photometric behavior.

Contribution

It provides evidence that the star's dimming is due to internal flux storage and cooling, not external obscuration, based on photometric passband analysis.

Findings

Reddening during dimming matches cooling of ~6800 K black body by 30K.

Photometric behavior supports internal flux storage hypothesis.

External obscuration sources are less likely to explain observed data.

Abstract

Two recent short term dimmings of KIC 8462852 (Boyajian's Star) exhibit clear reddening in the B, r' and i' photometric passbands. We show that the intensity ratios of the three pass bands agree well with cooling of an approximately 6800 K black body by about 30K. This agreement, together with other recent findings on the timing and longer term dimmings of this star, support our previous argument that the star's photometric behavior is caused by internal storage of impeded convective flux, rather than by external sources of obscuration such the ISM or circumstellar material.