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Near-IR Direct Detection of Water Vapor in Tau Boötis b

Lockwood, Alexandra C. and Johnson, John A. and Bender, Chad F. and Carr, John S. and Barman, Travis and Richert, Alexander J. W. and Blake, Geoffrey A. (2014) Near-IR Direct Detection of Water Vapor in Tau Boötis b. Astrophysical Journal Letters, 783 (2). Art. No. L29. ISSN 2041-8205.

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We use high dynamic range, high-resolution L-band spectroscopy to measure the radial velocity (RV) variations of the hot Jupiter in the τ Boötis planetary system. The detection of an exoplanet by the shift in the stellar spectrum alone provides a measure of the planet's minimum mass, with the true mass degenerate with the unknown orbital inclination. Treating the τ Boo system as a high flux ratio double-lined spectroscopic binary permits the direct measurement of the planet's true mass as well as its atmospheric properties. After removing telluric absorption and cross-correlating with a model planetary spectrum dominated by water opacity, we measure a 6σ detection of the planet at K_p = 111 ± 5 km s^(−1), with a 1σ upper limit on the spectroscopic flux ratio of 10^(−4). This RV leads to a planetary orbital inclination of i=45^(+3)_(-4)° and a mass of M_p = 5.90^(+0.35)_(-0.20)M_Jup. We report the first detection of water vapor in the atmosphere of a non-transiting hot Jupiter, τ Boo b.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Johnson, John A.0000-0001-9808-7172
Bender, Chad F.0000-0003-4384-7220
Carr, John S.0000-0002-6695-3977
Barman, Travis0000-0002-7129-3002
Richert, Alexander J. W.0000-0002-9613-6863
Blake, Geoffrey A.0000-0003-0787-1610
Additional Information:© 2014 American Astronomical Society. Received 2013 October 15; accepted 2014 February 3; published 2014 February 24. The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California and NASA, and was made possible by the financial support of the W. M. Keck Foundation. A.C.L. and G.A.B. gratefully acknowledge support from the NSF GRFP and AAG programs, JAJ the generous grants from the David and Lucile Packard and Alfred P. Sloan Foundations, and C.F.B. support from the Center for Exoplanets and Habitable Worlds, which is supported by the Pennsylvania State University, the Eberly College of Science, and the Pennsylvania Space Grant Consortium. Basic research in infrared astronomy at the Naval Research Laboratory is supported by 6.1 base funding. We thank Jacques Sauval for kindly providing a copy of his solar linelist. Finally, the authors wish to acknowledge the significant cultural role of the summit of Mauna Kea.
Funding AgencyGrant Number
NSF Graduate Research FellowshipUNSPECIFIED
David and Lucile Packard FoundationUNSPECIFIED
Alfred P. Sloan FoundationUNSPECIFIED
Center for Exoplanets and Habitable WorldsUNSPECIFIED
Subject Keywords:planets and satellites: atmospheres; techniques: spectroscopic
Issue or Number:2
Record Number:CaltechAUTHORS:20140429-083510877
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Official Citation:Near-IR Direct Detection of Water Vapor in Tau Boötis b Alexandra C. Lockwood et al. 2014 ApJ 783 L29
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:45267
Deposited By: Jason Perez
Deposited On:29 Apr 2014 18:19
Last Modified:09 Mar 2020 13:18

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