PROBABILISTIC MASS-RADIUS RELATIONSHIP for SUB-NEPTUNE-SIZED PLANETS

Angie Wolfgang, Leslie A. Rogers, Eric B. Ford

Research output: Contribution to journalArticle

72 Citations (Scopus)

Abstract

The Kepler Mission has discovered thousands of planets with radii <4 , paving the way for the first statistical studies of the dynamics, formation, and evolution of these sub-Neptunes and super-Earths. Planetary masses are an important physical property for these studies, and yet the vast majority of Kepler planet candidates do not have theirs measured. A key concern is therefore how to map the measured radii to mass estimates in this Earth-to-Neptune size range where there are no Solar System analogs. Previous works have derived deterministic, one-to-one relationships between radius and mass. However, if these planets span a range of compositions as expected, then an intrinsic scatter about this relationship must exist in the population. Here we present the first probabilistic mass-radius relationship (M-R relation) evaluated within a Bayesian framework, which both quantifies this intrinsic dispersion and the uncertainties on the M-R relation parameters. We analyze how the results depend on the radius range of the sample, and on how the masses were measured. Assuming that the M-R relation can be described as a power law with a dispersion that is constant and normally distributed, we find that , a scatter in mass of , and a mass constraint to physically plausible densities, is the "best-fit" probabilistic M-R relation for the sample of RV-measured transiting sub-Neptunes (R pl < 4 ). More broadly, this work provides a framework for further analyses of the M-R relation and its probable dependencies on period and stellar properties.

Original languageEnglish (US)
Article number19
JournalAstrophysical Journal
Volume825
Issue number1
DOIs
StatePublished - Jul 1 2016

Fingerprint

radii
Neptune (planet)
Neptune
planets
planet
Kepler mission
planetary mass
solar system
range size
physical properties
power law
physical property
analogs
estimates

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

@article{7bf99732e2364f578f6212e9d7d3c304,
title = "PROBABILISTIC MASS-RADIUS RELATIONSHIP for SUB-NEPTUNE-SIZED PLANETS",
abstract = "The Kepler Mission has discovered thousands of planets with radii <4 , paving the way for the first statistical studies of the dynamics, formation, and evolution of these sub-Neptunes and super-Earths. Planetary masses are an important physical property for these studies, and yet the vast majority of Kepler planet candidates do not have theirs measured. A key concern is therefore how to map the measured radii to mass estimates in this Earth-to-Neptune size range where there are no Solar System analogs. Previous works have derived deterministic, one-to-one relationships between radius and mass. However, if these planets span a range of compositions as expected, then an intrinsic scatter about this relationship must exist in the population. Here we present the first probabilistic mass-radius relationship (M-R relation) evaluated within a Bayesian framework, which both quantifies this intrinsic dispersion and the uncertainties on the M-R relation parameters. We analyze how the results depend on the radius range of the sample, and on how the masses were measured. Assuming that the M-R relation can be described as a power law with a dispersion that is constant and normally distributed, we find that , a scatter in mass of , and a mass constraint to physically plausible densities, is the {"}best-fit{"} probabilistic M-R relation for the sample of RV-measured transiting sub-Neptunes (R pl < 4 ). More broadly, this work provides a framework for further analyses of the M-R relation and its probable dependencies on period and stellar properties.",
author = "Angie Wolfgang and Rogers, {Leslie A.} and Ford, {Eric B.}",
year = "2016",
month = "7",
day = "1",
doi = "10.3847/0004-637X/825/1/19",
language = "English (US)",
volume = "825",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1",

}

PROBABILISTIC MASS-RADIUS RELATIONSHIP for SUB-NEPTUNE-SIZED PLANETS. / Wolfgang, Angie; Rogers, Leslie A.; Ford, Eric B.

In: Astrophysical Journal, Vol. 825, No. 1, 19, 01.07.2016.

Research output: Contribution to journalArticle

TY - JOUR

T1 - PROBABILISTIC MASS-RADIUS RELATIONSHIP for SUB-NEPTUNE-SIZED PLANETS

AU - Wolfgang, Angie

AU - Rogers, Leslie A.

AU - Ford, Eric B.

PY - 2016/7/1

Y1 - 2016/7/1

N2 - The Kepler Mission has discovered thousands of planets with radii <4 , paving the way for the first statistical studies of the dynamics, formation, and evolution of these sub-Neptunes and super-Earths. Planetary masses are an important physical property for these studies, and yet the vast majority of Kepler planet candidates do not have theirs measured. A key concern is therefore how to map the measured radii to mass estimates in this Earth-to-Neptune size range where there are no Solar System analogs. Previous works have derived deterministic, one-to-one relationships between radius and mass. However, if these planets span a range of compositions as expected, then an intrinsic scatter about this relationship must exist in the population. Here we present the first probabilistic mass-radius relationship (M-R relation) evaluated within a Bayesian framework, which both quantifies this intrinsic dispersion and the uncertainties on the M-R relation parameters. We analyze how the results depend on the radius range of the sample, and on how the masses were measured. Assuming that the M-R relation can be described as a power law with a dispersion that is constant and normally distributed, we find that , a scatter in mass of , and a mass constraint to physically plausible densities, is the "best-fit" probabilistic M-R relation for the sample of RV-measured transiting sub-Neptunes (R pl < 4 ). More broadly, this work provides a framework for further analyses of the M-R relation and its probable dependencies on period and stellar properties.

AB - The Kepler Mission has discovered thousands of planets with radii <4 , paving the way for the first statistical studies of the dynamics, formation, and evolution of these sub-Neptunes and super-Earths. Planetary masses are an important physical property for these studies, and yet the vast majority of Kepler planet candidates do not have theirs measured. A key concern is therefore how to map the measured radii to mass estimates in this Earth-to-Neptune size range where there are no Solar System analogs. Previous works have derived deterministic, one-to-one relationships between radius and mass. However, if these planets span a range of compositions as expected, then an intrinsic scatter about this relationship must exist in the population. Here we present the first probabilistic mass-radius relationship (M-R relation) evaluated within a Bayesian framework, which both quantifies this intrinsic dispersion and the uncertainties on the M-R relation parameters. We analyze how the results depend on the radius range of the sample, and on how the masses were measured. Assuming that the M-R relation can be described as a power law with a dispersion that is constant and normally distributed, we find that , a scatter in mass of , and a mass constraint to physically plausible densities, is the "best-fit" probabilistic M-R relation for the sample of RV-measured transiting sub-Neptunes (R pl < 4 ). More broadly, this work provides a framework for further analyses of the M-R relation and its probable dependencies on period and stellar properties.

UR - http://www.scopus.com/inward/record.url?scp=84978280174&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84978280174&partnerID=8YFLogxK

U2 - 10.3847/0004-637X/825/1/19

DO - 10.3847/0004-637X/825/1/19

M3 - Article

AN - SCOPUS:84978280174

VL - 825

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

M1 - 19

ER -