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The Smallest Mass Ratio Young Star Spectroscopic Binaries

L. Prato·M. Simon·T. Mazeh·I. S. McLean·D. Norman·S. Zucker
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Abstract

Using high resolution near-infrared spectroscopy with the Keck telescope, we have detected the radial velocity signatures of the cool secondary components in four optically identified pre-main-sequence, single-lined spectroscopic binaries. All are weak-lined T Tauri stars with well-defined center of mass velocities. The mass ratio for one young binary, NTTS 160905-1859, is M2/M1 = 0.18+/-0.01, the smallest yet measured dynamically for a pre-main-sequence spectroscopic binary. These new results demonstrate the power of infrared spectroscopy for the dynamical identification of cool secondaries. Visible light spectroscopy, to date, has not revealed any pre-main-sequence secondary stars with masses <0.5 M_sun, while two of the young systems reported here are in that range. We compare our targets with a compilation of the published young double-lined spectroscopic binaries and discuss our unique contribution to this sample.

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L. Prato, M. Simon, T. Mazeh, I. S. McLean, D. Norman, S. Zucker. 2002-01-19. The Smallest Mass Ratio Young Star Spectroscopic Binaries. https://doi.org/10.1086/339397

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