• DOI:10.1051/0004-6361:200810706
• Corpus ID: 6588381

Resolved debris disc emission around η Telescopii: a young solar system or ongoing planet formation?

@article{Smith2009ResolvedDD,
  title={Resolved debris disc emission around $\eta$ Telescopii: a young solar system or ongoing planet formation?},
  author={R. J. Smith and Laura Churcher and Mark C. Wyatt and Margaret Moerchen and Charles M. Telesco},
  journal={Astronomy and Astrophysics},
  year={2009},
  volume={493},
  pages={299-308}
}

• R. Smith, L. Churcher, +2 authors C. Telesco
• Published 28 October 2008
• Physics, Geology
• Astronomy and Astrophysics

Aims. 60% of the A star members of the 12 Myr oldβ Pictoris moving group (BPMG) show significant excess emissi on in the mid-infrared, several million years after the proto-plane tary disk is thought to disperse. Theoretical models suggest this peak may coincide with the formation of Pluto-sized planetesimals in the disk, stirring smaller bodies into collisional destru ction. Here we present resolved mid-infrared imaging of the disk ofη Tel (A0V in the BPMG) and consider its implications for the state of planet formation in this system. Methods.η Tel was observed at 11.7 and 18.3� m using T-ReCS on Gemini South. The resulting images were compared to simple disk models to constrain the radial distribution of the emit ting material. Results. The emission observed at 18.3� m is shown to be significantly extended beyond the PSF along a p osition angle 8 ◦ . This is the first time dust emission has been resolved around η Tel. Modelling indicates that the extension arises from an edge-on disk of radius 0.5 arcsec (∼ 24 AU). Combining the spatial constraints from the imaging with those from the spectral energy distribution shows that >50% of the 18� m emission comes from an unresolved dust component at∼4 AU. Conclusions. The radial structure of theη Tel debris disk is reminiscent of the Solar System, suggesting that this is a young Solar System analogue. For an age of 12Myr, both the radius and dust level of the extended cooler component are consistent with selfstirring models for a protoplanetary disk of 0.7 times minimum mass solar nebula. The origin of the hot dust component may arise in an asteroid belt undergoing collisional destruction, or in massive collisions in ongoing terrestrial planet formatio n.