Parallaxes of Southern Extremely Cool objects III: 118 L and T dwarfs
| Autor: | Mariateresa Crosta, Alexandre Humberto Andrei, J. L. Penna, D. N. da Silva Neto, D. J. Pinfield, Alessandro Sozzetti, Federico Marocco, Rene A. Mendez, M. Daprà, Alberto Vecchiato, R. Lachaume, Massimiliano Lattanzi, Julio Camargo, James S. Jenkins, Ben Burningham, Richard L. Smart, Beatrice Bucciarelli, V. A. d'Ávila, Bertrand Goldman, Hugh R. A. Jones |
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| Přispěvatelé: | ITA, USA, GBR, DEU, BRA, CHL, LaserLaB - Physics of Light, Atoms, Molecules, Lasers |
| Rok vydání: | 2018 |
| Předmět: |
Brown dwarf
Minimum mass Astrophysics 01 natural sciences law.invention Photometry (optics) Telescope low-mass [Stars] law 0103 physical sciences Stars: low-mass SDG 7 - Affordable and Clean Energy Variation (astronomy) 010303 astronomy & astrophysics Physics Brown dwarfs Parallaxes 010308 nuclear & particles physics Astronomy and Astrophysics Radius Stars Astrophysics - Solar and Stellar Astrophysics 13. Climate action Space and Planetary Science Proper motions Parallax |
| Zdroj: | Monthly Notices of the Royal Astronomical Society Monthly Notices of the Royal Astronomical Society, 481(3), 3548-3562. Oxford University Press Smart, R L, Bucciarelli, B, Jones, H R A, Marocco, F, Andrei, A H, Goldman, B, Mendez, R A, d'Avila, V A, Burningham, B, Camargo, J I B, Crosta, M T, Daprà, M, Jenkins, J S, Lachaume, R, Lattanzi, M G, Penna, J L, Pinfield, D J, da Silva Neto, D N, Sozzetti, A & Vecchiato, A 2018, ' Parallaxes of Southern Extremely Cool objects III : 118 L and T dwarfs ', Monthly Notices of the Royal Astronomical Society, vol. 481, no. 3, pp. 3548-3562 . https://doi.org/10.1093/mnras/sty2520 |
| ISSN: | 1365-2966 0035-8711 |
| DOI: | 10.1093/mnras/sty2520 |
| Popis: | We present new results from the Parallaxes of Southern Extremely Cool dwarfs program to measure parallaxes, proper motions and multi-epoch photometry of L and early T dwarfs. The observations were made on 108 nights over the course of 8 years using the Wide Field Imager on the ESO 2.2m telescope. We present 118 new parallaxes of L \& T dwarfs of which 52 have no published values and 24 of the 66 published values are preliminary estimates from this program. The parallax precision varies from 1.0 to 15.5 mas with a median of 3.8 mas. We find evidence for 2 objects with long term photometric variation and 24 new moving group candidates. We cross-match our sample to published photometric catalogues and find standard magnitudes in up to 16 pass-bands from which we build spectral energy distributions and H-R diagrams. This allows us to confirm the theoretically anticipated minimum in radius between stars and brown dwarfs across the hydrogen burning minimum mass. We find the minimum occurs between L2 and L6 and verify the predicted steep dependence of radius in the hydrogen burning regime and the gentle rise into the degenerate brown dwarf regime. We find a relatively young age of 2 Gyr from the kinematics of our sample. Comment: In press MNRAS |
| Databáze: | OpenAIRE |
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