Miranda HermanUniversity of Toronto

Revisiting the Long-Period Transiting Planets from Kepler

Long-period transiting planets are hard to find

Data from exoplanet.eu

Confirmed Exoplanets

Solar System Planets

Confirmed Exoplanets

Solar System Planets

Foreman-Mackey et al. (2016)candidates

Automating the search for long-period cold giants

Data from exoplanet.eu, Foreman-Mackey et al. (2016)

Revised stellar radii necessitate a reanalysis

Planet hosts in our sample

1:1 line

Herman, Zhu, & Wu (2019, submitted)

15 planet candidates from 61,418 stars

What can we learn from this sample of long-period cold giants?

Occurrence Rate

Radius Distribution

Correlation with Inner Systems

Occurrence Rate

Radius Distribution

Correlation with Inner Systems

~0.70 planets per Sun-like starwithin 0.3 – 1 RJ and 2 – 10 yr

Occurrence Rate

Radius Distribution

Correlation with Inner Systems

!"#! log'( ! log )

= + '(',

- )year

2

!#! log'(

∝ '(',

-

4 ∼ −7. 9

Radius distribution function follows a single power-law

Radius distribution function follows a single power-law

Cold Neptunes are ~4 timesmore common than cold Jupiters

Occurrence Rate

Radius Distribution

Correlation with Inner Systems

5 planet candidates have inner transiting companions

Herman, Zhu, & Wu (2019, submitted)

Average mutual inclination inthese systems must be low (~4o)

* not to scale

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Almost all cold giants should have inner companions

? @A BCDEF) ~ 89%

Confirmed Exoplanets

Solar System Planets

Herman, Zhu, & Wu (2019, submitted) candidates

Thank you, Kepler

Data from exoplanet.eu, Herman, Zhu, & Wu (2019, submitted)

Herman, Zhu, & Wu (2019, submitted)

arXiv: 1901.01974

Summary

o ~ 0.7 planets per Sun-like star within 0.3 – 1 RJ and 2 – 10 years

o Radius distribution of cold planets described by single power-law with α ~ -1.6

o Cold Neptunes are ~4 times more common than cold Jupiters

o Average mutual inclination in these systems is ~4o

o Almost all systems with outer planets should also have inner planets