Direct detection of a substellar companion to the young nearby star PZ Telescopii
Abstract
Aims: We study the formation of substellar objects (exoplanets and brown dwarfs) that are companions to young nearby stars.
Methods: With high-contrast AO imaging obtained with NACO at ESO VLT, we search for faint companion candidates around our targets, whose companionship can be confirmed with astrometry.
Results: We identified a faint substellar companion to the nearby pre-main sequence star PZ Tel, a member of the β Pic moving group. The companion is 5-6 mag fainter than its host star in JHK and is located at a separation of only 0.3 arcsec (or 15 AU of projected separation) northeast of PZ Tel. Within three NACO observing epochs, we can confirm the common proper motion (>39σ) and detected orbital motion of PZ Tel B around its primary (>37σ). The photometry of the newly found companion is consistent with a brown dwarf with a mass between 24 and 40 MJup, at the distance (50 pc) and age (8-20 Myr) of PZ Tel. The effective temperature of the companion, derived from its photometry, ranges between 2500 and 2700 K, which corresponds to a spectral type between M6 and M8. After β Pic b, PZ Tel B is the second closest substellar companion imaged directly around a young star.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- November 2010
- DOI:
- arXiv:
- arXiv:1008.4506
- Bibcode:
- 2010A&A...523L...1M
- Keywords:
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- stars: individual: PZ telescopii;
- brown dwarfs;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- accepted for publication in A&