American Association of Variable Star Observers (AAVSO)
Sun, 02/07/2021 - 22:56

I was looking at some TESS light curves for variables of different types and happened upon this interesting LC for NSV 18243 which is a composite of TESS sectors 9, 10 and 11.  I did an analysis of the deep drops every 4 or so days and obtained the phase plot shown which combines the TESS data with Hipparcos.  For the TESS data, the dips look like an EA, but I do not see them in the Hipparcos data.  Note that the period determined from ASAS3 and Hipparcos is 0.527 d for this star and that period does also occur in TESS.

I wonder if dips like these are characteristic of these pulsating B stars or whether this is actually a binary as well?

Thanks for any help in my understanding.


phase plotTESS LC
Variable Stars South (VSS)


My guess is you are right, and it's an EA+LPB.

There is only one star flagged as such in the GCVS - V0539 Ara.

There are two stars flagged as EA+LPB: where of course the ":" implies uncertainty on the type of variability. They are mu Eri and IL CMa.