Orbits of four triple stars

These stars are relatively young (between 100 and 600Myr) and chromospherically active (X-ray sources), although they rotate slowly. I determine the spectroscopic orbits of the inner subsystems (periods 19.4, 14.1, 5.6, 20.3days) and the orbits of the outer systems (periods 1.75, 51, 27, 500years, respectively).

For HIP 7601 and 13498, the combined spectro-interferometric outer orbits produce direct measurement of the masses of all of the components, allowing for a comparison with stellar models. The 6708{AA} lithium line is present and its strength is measured in each component individually by subtracting the contributions of the other components. The inner and outer orbits of HIP 7601 are nearly circular, likely co-planar, and have a modest period ratio of 1:33.