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Young and Eccentric: The Quadruple System HD 86588 Tokovinin, Andrei Corbett, Hank Fors Aldrich, Octavi Howard, Ward Law, Nicholas M. Moe, Maxwell Ratzloff, Jeffrey K. Walter, Frederick M. Espectroscòpia astronòmica Interferometria Estels Astronomical spectroscopy Interferometry Stars High-resolution spectroscopy and speckle interferometry reveal the young star HD 86588 as a quadruple system with a three-tier hierarchy. The 0 3 resolved binary A,B with an estimated period around 300 years contains the 8-yr pair Aa,Abc (also potentially resolvable), where Ab,Ac is a double-lined binary with equal components, for which we compute the spectroscopic orbit. Despite the short period of 2.4058 days, the orbit of Ab,Ac is eccentric (e=0.086±0.003)). It has a large inclination, but there are no eclipses; only a 4.4 mmag light modulation apparently caused by star spots on the components of this binary is detected with Evryscope. Assuming a moderate extinction of AV=0.5 mag and a parallax of 5.2 mas, we find that the stars are on or close to the main sequence (age >10 Myr) and their masses are from 1 to 1.3 solar. We measure the strength of the lithium line in the visual secondary B which, together with rotation, suggests that the system is younger than 150 Myr. This object is located behind the extension of the Chamaeleon I dark cloud (which explains extinction and interstellar sodium absorption), but apparently does not belong to it. We propose a scenario where the inner orbit has recently acquired its high eccentricity through dynamical interaction with the outer two components; it is now undergoing rapid tidal circularization on a timescale of ∼1 Myr. Alternatively, the eccentricity could be excited quasi-stationary by the outer component Aa. 2019-06-06T11:27:11Z 2019-06-06T11:27:11Z 2018-08-24 2019-06-06T11:24:41Z info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 0004-6256 https://hdl.handle.net/2445/134583 689252 eng Reproducció del document publicat a: https://doi.org/10.3847/1538-3881/aad694 Astronomical Journal, 2018, vol. 156, num. 3, p. 120-128 https://doi.org/10.3847/1538-3881/aad694 (c) American Astronomical Society, 2018 info:eu-repo/semantics/openAccess 9 p. application/pdf Institute of Physics (IOP) Articles publicats en revistes (Institut de Ciències del Cosmos (ICCUB))