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arXiv · 1707.00691

Four years' interferometric observations of Galactic binary Cepheids

A. Gallenne·A. Merand·P. Kervella·N. R. Evans·C. Profitt·G. Pietrzynski·W. Gieren
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Abstract

We give an update on our long-term program of Galactic Cepheids started in 2012, whose goal is to measure the visual orbits of Cepheid companions. Using the VLTI/PIONIER and CHARA/MIRC instruments, we have now detected several com- panions, and we already have a good orbital coverage for several of them. By combining interferometry and radial velocities, we can now derive all the orbital elements of the systems, and we will be soon able to estimate the Cepheid masses.

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A. Gallenne, A. Merand, P. Kervella, N. R. Evans, C. Profitt, G. Pietrzynski, W. Gieren. 2017-07-03. Four years' interferometric observations of Galactic binary Cepheids. https://doi.org/10.1051/epjconf%2F201715203007

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