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arXiv · 1102.2622

Misaligned And Alien Planets From Explosive Death Of Stars

Shlomo Dado·Arnon Dar·Erez Ribak
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Abstract

Exoplanets whose orbit is misaligned with the spin of their host star could have originated from high-speed gas blobs, which are observed in multitudes in nearby supernova remnants and planetary nebulae. These blobs grow in mass and slow down in the interstellar medium (ISM) by mass accretion and cool by radiation. If their mass exceeds the Jeans mass, they collapse into hot giant gas planets. Most of the 'missing baryons' in galaxies could have been swept into such free-floating objects, which could perturb stellar planetary systems, kick bound planets into misaligned orbits or be captured themselves into misaligned orbits. The uncollapsed ones can then collapse or be tidally disrupted into a tilted gas disk where formation of misaligned planets can take place. Giant gas planets free floating in the Galactic ISM may be detected by their microlensing effects or by deep photometry if they are hot. The uncollapsed gas blobs may produce the observed radio scintillations of comact extragalactic radio sources such as quasars and gamma ray bursts.

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Shlomo Dado, Arnon Dar, Erez Ribak. 2011-06-16. Misaligned And Alien Planets From Explosive Death Of Stars. https://arxiv.org/abs/1102.2622

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