2024/06/06 by Maxted, P. F. L., Miller, N. J., Sebastian, D. +3
#FOS: Physical sciences #Solar and Stellar Astrophysics (astro-ph.SR)
paper · doi:10.48550/arxiv.2406.04204
EBLM J0608-59 / TOI-1338 / BEBOP-1 is a 12th-magnitude, F9V star in an eclipsing binary with a much fainter M-dwarf companion on a wide, eccentric orbit (P=14.6 d). The binary is orbited by two circumbinary planets: one transiting on a 95-day orbit and one non-transiting on a 215-day orbit. We have used high-precision photometry from the TESS mission combined with direct mass measurements for the two stars published recently to measure the following model-independent radii: R1 = 1.32 ± 0.02 R\odot, R2 = 0.309 ± 0.004 R\odot. Using R1 and the parallax from Gaia EDR3 we find that this star's angular diameter is θ= 0.0309 ± 0.0005 mas. The apparent bolometric flux of the primary star corrected for both extinction and the contribution from the M-dwarf (<0.4%) is \mathcal F⊕,0 = (0.417± 0.005)×10-9 \rm erg cm-2 \rm s-1. Hence, this F9V star has an effective temperature T\rm eff,1 = 6031\rm K ± 46\rm K (rnd.) ± 10 \rm K (sys.). EBLM J0608-59 is an ideal benchmark star that can be added to the sample of such systems we are establishing for "end-to-end" tests of the stellar parameters measured by large-scale spectroscopic surveys.