Imperial College London
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DrJamesOwen

Faculty of Natural Sciences, Department of Physics

Senior Lecturer in Exoplanet Physics
 
 
 
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Contact

 

+44 (0)20 7594 5785james.owen CV

 
 
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Location

 

Blackett LaboratorySouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Van:2018:mnras/sty1783,
author = {Van, Eylen V and Agentoft, C and Lundkvist, M and Kjeldsen, H and Owen, JE and Fulton, B and Petigura, E and Snellen, I},
doi = {mnras/sty1783},
journal = {Monthly Notices of the Royal Astronomical Society},
pages = {4786--4795},
title = {An asteroseismic view of the radius valley: stripped cores, not born rocky},
url = {http://dx.doi.org/10.1093/mnras/sty1783},
volume = {479},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Various theoretical models treating the effect of stellar irradiation on planetary envelopes predict the presence of a radius valley, i.e. a bimodal distribution of planet radii, with super-Earths and sub-Neptune planets separated by a valley at around≈2R⊕. Such a valley has been observed recently, owing to an improvement in the precision of stellar and therefore planetary radii. Here, we investigate the presence, location, and shape of such a valley using a small sample with highly accurate stellar parameters determined from asteroseismology, which includes 117 planets with a median uncertainty on the radius of 3.3 per cent. We detect a clear bimodal distribution, with super-Earths (≈1.5R⊕) and sub-Neptunes (≈2.5 R⊕) separated by a deficiency around2R⊕. We furthermore characterize the slope of the valley as a power law R∝Pγ withγ=−0.09+0.02−0.04. A negative slope is consistent with models of photoevaporation, but not with the late formation of rocky planets in a gas-poor environment, which would lead to a slope of opposite sign. The exact location of the gap further points to planet cores consisting of a significant fraction of rocky material.
AU  - Van,Eylen V
AU  - Agentoft,C
AU  - Lundkvist,M
AU  - Kjeldsen,H
AU  - Owen,JE
AU  - Fulton,B
AU  - Petigura,E
AU  - Snellen,I
DO  - mnras/sty1783
EP  - 4795
PY  - 2018///
SN  - 0035-8711
SP  - 4786
TI  - An asteroseismic view of the radius valley: stripped cores, not born rocky
T2  - Monthly Notices of the Royal Astronomical Society
UR  - http://dx.doi.org/10.1093/mnras/sty1783
UR  - http://hdl.handle.net/10044/1/61934
VL  - 479
ER  -
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