2002/12/19 by Jocelyn Tomkin, Tomkin, Jocelyn
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0212454
3 figures
arxiv created 2002/12/19 · arxiv updated 2009/12/01
A new determination of the orbit of the Hyades double-lined spectroscopic binary HD 27149 is presented. The well-defined orbit provides the spectroscopic basis for an extremely accurate orbital parallax for the system -- in particular, the size of the relative orbit (asin i = (a1 + a2)sin i = (67.075 ± 0.045) × 106 km) is accurate to ± 0.07 %. The minimum masses for the primary and secondary -- m1sin 3i = 1.096 ± 0.002 M_\odot and m2sin 3i = 1.010 ± 0.002 M_\odot -- are unexpectedly large for the spectral types thus suggesting the possibility of eclipses. Although the probability of eclipses is not large, the system being composed of G3V and G6V stars in a 75-day orbit, the possibility is of great interest. A rediscussion of a search for eclipses made by Jørgensen & Olsen1 in 1972 shows that central eclipses can be excluded, but that shorter duration off-centre eclipses cannot be ruled out. Ephemerides for possible primary and secondary eclipses are given.