Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2011-05-10
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
41 pages in preprint style, 15 figures, final version accepted to ApJ
Scientific paper
We demonstrate that the observed distribution of `Hot Neptune'/`Super-Earth' systems is well reproduced by a model in which planet assembly occurs in situ, with no significant migration post-assembly. This is achieved only if the amount of mass in rocky material is $\sim 50$--$100 M_{\oplus}$ interior to 1 AU. Such a reservoir of material implies that significant radial migration of solid material takes place, and that it occur before the stage of final planet assembly. The model not only reproduces the general distribution of mass versus period, but also the detailed statistics of multiple planet systems in the sample. We furthermore demonstrate that cores of this size are also likely to meet the criterion to gravitationally capture gas from the nebula, although accretion is rapidly limited by the opening of gaps in the gas disk. If the mass growth is limited by this tidal truncation, then the scenario sketched here naturally produces Neptune-mass objects with substantial components of both rock and gas, as is observed. The quantitative expectations of this scenario are that most planets in the `Hot Neptune/Super-Earth' class inhabit multiple-planet systems, with characteristic orbital spacings. The model also provides a natural division into gas-rich (Hot Neptune) and gas-poor (Super-Earth) classes at fixed period. The dividing mass ranges from $\sim 3 M_{\oplus}$ at 10 day orbital periods to $\sim 10 M_{\oplus}$ at 100 day orbital periods. For orbital periods $< 10$ days, the division is less clear because a gas atmosphere may be significantly eroded by stellar radiation.
Hansen Brad M. S.
Murray Norm
No associations
LandOfFree
Migration then assembly: Formation of Neptune mass planets inside 1 AU does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Migration then assembly: Formation of Neptune mass planets inside 1 AU, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Migration then assembly: Formation of Neptune mass planets inside 1 AU will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-610790