Erratum for: A&A, 643, A9 (2020), https://doi.org/10.1051/0004-6361/202038791

Equation (14) for the duration d of an eclipse with respect to the orbital period P is wrong. If we assume a spherical donor star of radius R and a circular orbit of the compact object around the donor star with orbital separation a, the right formula is: $$\frac{d}{P}=\frac{1}{\pi }\arcsin \left(\frac{\sqrt{R^2-a^2{\cos }^{2}i}}{a\sin i}\right),$$(1)

where i is the orbital inclination (i = 90° for an edge-on configuration). We retrieve the condition R < acosi to have an eclipse of the X-ray point source by the donor star. This equation did not directly intervene in the other computations performed in the paper so it does not change the conclusions, neither qualitatively nor quantitatively.

© ESO 2020