Wei Zhu
I'm now an Assistant Professor in the Department of Astronomy at Tsinghua University in Beijing.
Canadian Institute for Theoretical Astrophysics
Extreme Solar System IV
2019-08-22, Reykjavik
Image from Lissauer et al. (2011)
Outer-to-inner radius ratio
Outer planet larger
Inner planet larger
0.4 \(R_\oplus\)
0.9 \(R_\oplus\)
1.0 \(R_\oplus\)
0.5 \(R_\oplus\)
11 \(R_\oplus\)
9 \(R_\oplus\)
4.0 \(R_\oplus\)
3.9 \(R_\oplus\)
Cold Jupiters
Super Earths
22 from Kepler (triangles) + 39 from RV (squares)
(see also Bryan et al. 2019, Herman, Zhu, & Wu 2019)
Cold Jupiters
Super Earths
22 from Kepler (triangles) + 39 from RV (squares)
(see also Bryan et al. 2019, Herman, Zhu, & Wu 2019)
Cold Jupiters
Super Earths
22 from Kepler (triangles) + 39 from RV (squares)
(see also Bryan et al. 2019, Herman, Zhu, & Wu 2019)
Miranda Herman
HATNet
Keck
Cold Jupiters
(~10%)
Cold Neptunes
From Weiss et al. (2018)
Noisy sample
Quiet sample
Data from Weiss et al. (2018)
CDPP CDF
From Ciardi et al. (2013)
Kepler detections pile up toward the
detection threshold.
Correlation strength \(r\)
Forward modeling
A more proper way is fully forward modeling the detection and selection processes from the intrinsic planetary (radius or mass) distribution. Instead of randomly drawing parameters from the observed distribution, one should draw from the intrinsic distribution and then apply the same detection criteria (e.g., S/N cut) on these simulated planets. This process requires knowing the intrinsic planet distribution function and having access to the automated Kepler detection pipeline. It is further complicated by the fact that the planet distribution function is period dependent (e.g., Dong, & Zhu 2013; Hsu et al. 2019) and possibly multiplicity dependent, and that the Kepler detection efficiency is weakly multiplicity dependent (Zink et al. 2019).
There is a shortcut that circumvents these problems. As it is the transit S/N that determines whether or not a planet is detected, we can simply start from the observed S/N distribution.
Page 2 of Zhu, arXiv:1907.02074
Period ratio of inner pair
Period ratio of outer pair
Stability
boundary
Systems around
Period ratio of inner pair
Period ratio of outer pair
Systems around
Data used in Weiss et al. (2018)
All planet triplets
Q: Do planets show intra-system uniformity intrinsically?
Period ratio of inner pair
Period ratio of outer pair
Stability boundary
Noisy stars
Intermediate stars
Quiet stars
By Wei Zhu