Previous works on Kepler multi-planet systems revealed a remarkable intra-system uniformity in planet radius/mass ; moreover the average planet size increases with host mass/metallicity .
This observation provides tantalizing evidence that the outcome of planet formation can be linked to the properties of the host star and its disk .
In a simple in-situ formation scenario , the minimum-mass extrasolar nebula ( MMEN ) reconstructed from a planetary system reflect the properties of its natal disk.Specifically , one might expect a one-to-one correspondence between the solid surface density of the MMEN and the host star mass M _ { \star } and metallicity [ Fe/H ] .
Leveraging on the precise host star properties from the California- Kepler -Survey ( CKS ) , we found that \Sigma = 50 ^ { +33 } _ { -20 } { ~ { } g~ { } cm } ^ { -2 } ( a / { AU } ) ^ { -1.75 \pm 0.07 } ( M _ { \star } / M _ { \odot } ) ^ { 1.04 \pm 0.22 } 10 ^ { 0.22 \pm 0.05 { [ Fe / H ] } } for Kepler -like systems ( 1-4 R _ { \oplus } ; a < 1AU ) .
The strong M _ { \star } dependence is reminiscent of previous dust continuum results that the solid disk mass scales with M _ { \star } .
The weaker [ Fe/H ] dependence shows that sub-Neptune planets , unlike giant planets , form readily in lower-metallicity environment .
The innermost region ( a < 0.1AU ) of a MMEN maintains a smooth profile despite a steep decline of planet occurrence rate : a result that favors the truncation of disks by co-rotating magnetospheres with a range of rotation periods , rather than the sublimation of dusts .
The \Sigma of Kepler multi-transiting systems shows a much stronger correlation with M _ { \star } and [ Fe/H ] than singles .
This suggests that the dynamically hot evolution that produced single systems also partially removed the memory of formation in disks .
Radial-velocity planets yielded a MMEN very similar to CKS planets ; whereas transit-timing-variation planets ’ postulated convergent migration history is supported by their poorly constrained MMEN .
We found that lower-mass stars have a higher efficiency of forming/retaining planets : for sun-like stars about 20 % of the solid mass within \sim 1AU are converted/preserved as sub-Neptunes , compared to 70 % for late-K-early-M stars .
This may be due to the lower binary fraction , lower giant-planet occurrence or the longer disk lifetime of lower-mass stars .