Back to Volume
Paper: Ground Based Astrometric Search for Substellar Companions in Stellar Multiple Systems, The Case of the Exoplanet Host System HD 19994
Volume: 435, Binaries – Key to Comprehension of the Universe
Page: 419
Authors: Röll, T.; Seifahrt, A.; Neuhäuser, R.; Köhler, R.
Abstract: Due to the unknown inclination angle, radial velocity (RV) measurements only provide the minimum mass of companions. In combination with transit observations one can derive the true mass, but a transit is only observable for nearly edge-on systems. For all other systems, astrometry is the only method to get the true mass of an orbiting companion by measuring the reflex motion of the host star. In our ongoing astrometric search program we observe stellar multiple systems within a distance of 100 parsec in order to confirm RV exoplanet candidates and to search for unknown substellar companions. Here we present preliminary results of one of our targets, the binary HD 19994, which is known to harbour a RV planet candidate around the A component. From our astrometric observations over the last years, it seems that a high mass brown dwarf is orbiting the low-mass B component. Analysis of our data with speckle interferometry confirms the existence of an additional body.
Back to Volume