SIMBAD references

Stellar companion within a few hundred astronomical unit alter the structure and shorten the lifetime of protoplanetary disks, influencing planetary formation and evolution. Such systems host fewer close-in planets, and have fewer ∼2.3R_⊕ “sub-Neptunes” relative to ∼1.3R_⊕ “super-Earths” compared to single-star hosts, observations that can be explained by early dissipation of the gas disk. Here we construct the mass-radius diagram of 15 small (<8R_⊕), well-characterized planets on S-type orbits in systems with projected separations <500 au, and show that it is indistinguishable from that of planets around single stars. This suggests that accretion of the H₂-dominated envelopes of sub-Neptunes could be much faster than gas disk dissipation and limited instead by available solids for cores, or that many sub-Neptunes have envelopes of condensible volatiles such as H₂O.