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arXiv · 1007.4808

The Gemini NICI Planet-Finding Campaign: Discovery of a Close Substellar Companion to the Young Debris Disk Star PZ Tel

Beth A. Biller·Michael C. Liu·Zahed Wahhaj·Eric L. Nielsen·Laird M. Close·Trent J. Dupuy·Thomas L. Hayward·Adam Burrows·Mark Chun·Christ Ftaclas·Fraser Clarke·Markus Hartung·Jared Males·I. Neill Reid·Evgenya L. Shkolnik·Andrew Skemer·Matthias Tecza·Niranjan Thatte·Silvia H. P. Alencar·Pawel Artymowicz·Alan Boss·Elisabete de Gouveia Dal Pino·Jane Gregorio-Hetem·Shigeru Ida·Marc J. Kuchner·Douglas Lin·Douglas Toomey
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Abstract

We report the discovery of a tight substellar companion to the young solar analog PZ Tel, a member of the Beta Pictoris moving group observed with high contrast adaptive optics imaging as part of the Gemini NICI Planet-Finding Campaign. The companion was detected at a projected separation of 16.4 +/- 1.0 AU (0.33 +/- 0.01") in April 2009. Second-epoch observations in May 2010 demonstrate that the companion is physically associated and shows significant orbital motion. Monte Carlo modeling constrains the orbit of PZ Tel B to eccentricities > 0.6. The near-IR colors of PZ Tel B indicate a spectral type of M7+/-2 and thus this object will be a new benchmark companion for studies of ultracool, low-gravity photospheres. Adopting an age of 12 +8 -4 Myr for the system, we estimate a mass of 36 +/- 6 Mjup based on the Lyon/DUSTY evolutionary models. PZ Tel B is one of few young substellar companions directly imaged at orbital separations similar to those of giant planets in our own solar system. Additionally, the primary star PZ Tel A shows a 70 um emission excess, evidence for a significant quantity of circumstellar dust that has not been disrupted by the orbital motion of the companion.

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Beth A. Biller, Michael C. Liu, Zahed Wahhaj, Eric L. Nielsen, Laird M. Close, Trent J. Dupuy, Thomas L. Hayward, Adam Burrows, Mark Chun, Christ Ftaclas, Fraser Clarke, Markus Hartung, Jared Males, I. Neill Reid, Evgenya L. Shkolnik, Andrew Skemer, Matthias Tecza, Niranjan Thatte, Silvia H. P. Alencar, Pawel Artymowicz, Alan Boss, Elisabete de Gouveia Dal Pino, Jane Gregorio-Hetem, Shigeru Ida, Marc J. Kuchner, Douglas Lin, Douglas Toomey. 2010-07-27. The Gemini NICI Planet-Finding Campaign: Discovery of a Close Substellar Companion to the Young Debris Disk Star PZ Tel. https://doi.org/10.1088/2041-8205/720/1/l82

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