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arXiv · 2103.12963

On the Period-Ratio-Mass-Ratio Correlation of Extra-Solar Multi-Planet Systems

Sridhar Gajendran·Li-Chin Yeh·Ing-Guey Jiang
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Abstract

In order to gain possible hints for planet formation from the current data of known extra-solar planets, the period-ratios and mass-ratios of adjacent planet pairs in multi-planet systems are determined. A moderate period-ratio-mass-ratio correlation is found to have a correlation coefficient r=0.5779 with 99% confidence interval (0.464, 0.672). In contrast, for non-adjacent planet pairs, the correlation coefficient is r=0.2820 with 99% confidence interval (0.133, 0.419). Our results reveal the imprint of planet-planet interactions of the adjacent planet pairs in a certain fraction of the multi-planet systems during the stage of planet formation.

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Sridhar Gajendran, Li-Chin Yeh, Ing-Guey Jiang. 2021-03-24. On the Period-Ratio-Mass-Ratio Correlation of Extra-Solar Multi-Planet Systems. https://doi.org/10.1016/j.newast.2021.101602

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