Molecular Hydrogen emission from disks in the eta Chamaeleontis cluster
نویسنده
چکیده
Disks in the 6 Myr old cluster η Chamaeleontis were searched for emission from hot H2 . Around the M3 star ECHA J0843.4-7905 we detect circumstellar gas orbiting at ∼2 AU. If the gas is UV-excited, the ro-vibrational line traces a hot gas layer supported by a disk of mass ∼0.03 M⊙ , similar to the minimum mass solar nebula. Such a gas reservoir at 6 Myr would promote the formation and inwards migration of gas giant planets.
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