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تسجيل مستخدم جديدPlanet formation in binary systems: A separation-dependent mechanism?
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G. Duchene
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In this article, I examine several observational trends regarding protoplanetary disks, debris disks and exoplanets in binary systems in an attempt to constrain the physical mechanisms of planet formation in such a context. Binaries wider than about 100 AU are indistinguishable from single stars in all aspects. Binaries in the 5-100 AU range, on the other hand, are associated with shorter-lived but (at least in some cases) equally massive disks. Furthermore, they form planetesimals and mature planetary systems at a similar rate as wider binaries and single stars, albeit with the peculiarity that they predominantly produce high-mass planets. I posit that the location of a stellar companion influences the relative importance of the core accretion and disk fragmentation planet formation processes, with the latter mechanism being predominant in binaries tighter than 100 AU.
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