A DEFINITION FOR GIANT PLANETS BASED ON THE MASS-DENSITY RELATIONSHIP

作者：Hatzes Artie P^*; Rauer Heike

来源：Astrophysical Journal Letters, 2015, 810(2): L25.

DOI：10.1088/2041-8205/810/2/L25

• brown dwarfs
• planets and satellites: fundamental parameters
• stars: low-mass

We present the mass-density relationship (log M-log.) for objects with masses ranging from planets (M approximate to 0.01 M-Jup) to stars (M > 0.08M circle dot). This relationship shows three distinct regions separated by a change in slope in the log M-log rho plane. In particular, objects with masses in the range 0.3M(Jup)-60M(Jup) follow a tight linear relationship with no distinguishing feature to separate the low-mass end (giant planets) from the high-mass end (brown dwarfs). We propose a new definition of giant planets simply based on changes in the slope of the log M versus log. relationship. By this criterion, objects with masses less than approximate to 0.3M(Jup) are low-mass planets, either icy or rocky. Giant planets cover the mass range 0.3MJup-60MJup. Analogous to the stellar main sequence, objects on the upper end of the giant planet sequence (brown dwarfs) can simply be referred to as "high-mass giant planets, "while planets with masses near that of Jupiter can be called "low-mass giant planets."

• 出版日期2015-9-10