The EBLM project -- VIII. First results for M-dwarf mass, radius and effective temperature measurements using CHEOPS light curves
Abstract
The accuracy of theoretical mass, radius and effective temperature values for M-dwarf stars is an active topic of debate. Differences between observed and theoretical values have raised the possibility that current theoretical stellar structure and evolution models are inaccurate towards the low-mass end of the main sequence. To explore this issue we use the CHEOPS satellite to obtain high-precision light curves of eclipsing binaries with low mass stellar companions. We use these light curves combined with the spectroscopic orbit for the solar-type companion to measure the mass, radius and effective temperature of the M-dwarf star. Here we present the analysis of three eclipsing binaries. We use the pycheops data analysis software to fit the observed transit and eclipse events of each system. Two of our systems were also observed by the TESS satellite -- we similarly analyse these light curves for comparison. We find consistent results between CHEOPS and TESS, presenting three stellar radii and two stellar effective temperature values of low-mass stellar objects. These initial results from our on-going observing programme with CHEOPS show that we can expect to have ~24 new mass, radius and effective temperature measurements for very low mass stars within the next few years.
Cite
@article{arxiv.2106.07276,
title = {The EBLM project -- VIII. First results for M-dwarf mass, radius and effective temperature measurements using CHEOPS light curves},
author = {M. I. Swayne and P. F. L. Maxted and A. H. M. J. Triaud and S. G. Sousa and C. Broeg and H. -G. Florén and P. Guterman and A. E. Simon and I. Boisse and A. Bonfanti and D. Martin and A. Santerne and S. Salmon and M. R. Standing and V. Van Grootel and T. G. Wilson and Y. Alibert and R. Alonso and G. Anglada Escudé and J. Asquier and T. Bárczy and D. Barrado and S. C. C. Barros and M. Battley and W. Baumjohann and M. Beck and T. Beck and A. Bekkelien and W. Benz and N. Billot and X. Bonfils and A. Brandeker and M. -D. Busch and J. Cabrera and S. Charnoz and A. Collier Cameron and Sz. Csizmadia and M. B. Davies and M. Deleuil and A. Deline and L. Delrez and O. D. S. Demangeon and B. -O. Demory and G. Dransfield and D. Ehrenreich and A. Erikson and A. Fortier and L. Fossati and M. Fridlund and D. Futyan and D. Gandolfi and M. Gillon and M. Guedel and G. Hébrard and N. Heidari and C. Hellier and K. Heng and M. Hobson and S. Hoyer and K. G. Isaak and L. Kiss and V. Kunovac Hodžić and S. Lalitha and J. Laskar and A. Lecavelier des Etangs and M. Lendl and C. Lovis and D. Magrin and L. Marafatto and J. McCormac and N. Miller and V. Nascimbeni and G. Olofsson and R. Ottensamer and I. Pagano and E. Pallé and G. Peter and G. Piotto and D. Pollacco and D. Queloz and R. Ragazzoni and N. Rando and H. Rauer and I. Ribas and N. C. Santos and G. Scandariato and D. Ségransan and A. M. S. Smith and M. Steinberger and M. Steller and Gy. M. Szabó and N. Thomas and S. Udry and I. Walter and N. A. Walton and E. Willett},
journal= {arXiv preprint arXiv:2106.07276},
year = {2021}
}
Comments
12 pages, 8 figures, accepted for publication in MNRAS