Year: 2017
Type: article
Abstract: We report results of an extended spectropolarimetric and ph\notometric monitoring of the weak-\nline T Tauri star V830 Tau and its recently-detected newborn\nclose-in giant planet. Our obser-\nvations, carried out within the MaTYSSE programme, were spr\nead over 91 d, and involved the\nESPaDOnS and Narval spectropolarimeters linked to the 3.6-\nm Canada-France-Hawaii, the 2-\nm Bernard Lyot and the 8-m Gemini-North Telescopes. Using Ze\neman-Doppler Imaging, we\ncharacterize the surface brightness distributions, magne\ntic topologies and surface di\nff\nerential\nrotation of V830 Tau at the time of our observations, and demo\nnstrate that both distributions\nevolve with time beyond what is expected from di\nff\nerential rotation. We also report that near\nthe end of our observations, V830 Tau triggered one major flar\ne and two weaker precursors,\nshowing up as enhanced red-shifted emission in multiple spe\nctral activity proxies.\nWith 3 di\nff\nerent filtering techniques, we model the radial velocity (RV\n) activity jitter (of\nsemi-amplitude 1.2 km s\n−\n1\n) that V830 Tau generates, successfully retrieve the 68\n±\n11 m s\n−\n1\nRV planet signal hiding behind the jitter, further confirm th\ne existence of V830 Tau b and\nbetter characterize its orbital parameters. We find that the\nmethod based on Gaussian-process\nregression performs best thanks to its higher ability at mod\nelling not only the activity jitter, but\nalso its temporal evolution over the course of our observati\nons, and succeeds at reproducing\nour RV data down to a rms precision of 35 m s\n−\n1\n. Our result provides new observational\nconstraints on scenarios of star\n/\nplanet formation and demonstrates the scientific potential\nof\nlarge-scale searches for close-in giant planets around T Ta\nuri stars.
Author: A. A. Vidotto
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Chinese Academy of Sciences, Ministerio de Ciencia, Tecnología e Innovación Productiva, Ministério da Ciência, Tecnologia e Inovação, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Centre National de la Recherche Scientifique, National Research Council Canada, Science and Technology Facilities Council, Comisión Nacional de Investigación Científica y Tecnológica, Institut national des sciences de l'Univers
OpenAlex ID: W2591077870