SIMBAD references

HD 75767 is a nearby solar-type star. It has an unseen companion with which it is in an orbit that is very slightly off-circular and has a period of about 10d. In addition, it has a faint visual companion. Wraight et al., in a recent paper, have built a considerable edifice on the idea that the orbital period has shown a perceptible change within the last 100 yr. We point out that the phase shift that constitutes their evidence for such a change arises only from their use of their own, relatively inaccurate, value for the period.

Rotational-velocity measurements for HD 75767, published independently by each of the authors and by others, have all been smaller than would correspond to the equatorial velocity if the star's rotation were synchronized to the orbital revolution. Each of the present authors has accordingly proposed (explicitly on the assumption of synchronism) an inclination corresponding to his favoured value of vsini. There is, therefore, implicit surprise at the discovery by Wraight et al. that the system exhibits eclipses and therefore the orbital inclination must be close to 90°. The logical conclusion must be that the star is rotating more slowly than would correspond to synchronism with the orbit.