Details

Autor(en) / Beteiligte

• Jackman, James A G
• Wheatley, Peter J
• Bayliss, Dan
• Gill, Samuel
• Hodgkin, Simon T
• Burleigh, Matthew R
• Braker, Ian P
• Günther, Maximilian N
• Louden, Tom
• Turner, Oliver
• Anderson, David R
• Belardi, Claudia
• Bouchy, François
• Briegal, Joshua T
• Bryant, Edward M
• Cabrera, Juan
• Casewell, Sarah L
• Chaushev, Alexander
• Costes, Jean C
• Csizmadia, Szilard
• Eigmüller, Philipp
• Erikson, Anders
• Gänsicke, Boris T
• Gillen, Edward
• Goad, Michael R
• Jenkins, James S
• McCormac, James
• Moyano, Maximiliano
• Nielsen, Louise D
• Pollacco, Don
• Poppenhaeger, Katja
• Queloz, Didier
• Rauer, Heike
• Raynard, Liam
• Smith, Alexis M S
• Udry, Stéphane
• Vines, Jose I
• Watson, Christopher A
• West, Richard G

Titel

NGTS-7Ab: an ultrashort-period brown dwarf transiting a tidally locked and active M dwarf

Ist Teil von

• Monthly notices of the Royal Astronomical Society, 2019-11, Vol.489 (4), p.5146-5164

Ort / Verlag

Oxford University Press

Erscheinungsjahr

2019

Link zum Volltext

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• ABSTRACT We present the discovery of NGTS-7Ab, a high-mass brown dwarf transiting an M dwarf with a period of 16.2 h, discovered as part of the Next Generation Transit Survey (NGTS). This is the shortest period transiting brown dwarf around a main or pre-main sequence star to date. The M star host (NGTS-7A) has an age of roughly 55 Myr and is in a state of spin–orbit synchronization, which we attribute to tidal interaction with the brown dwarf acting to spin-up the star. The host star is magnetically active and shows multiple flares across the NGTS and follow-up light curves, which we use to probe the flare–star-spot phase relation. The host star also has an M star companion at a separation of 1.13 arcsec with very similar proper motion and systemic velocity, suggesting that the NGTS-7 system is a hierarchical triple. The combination of tidal synchronisation and magnetic braking is expected to drive on-going decay of the brown dwarf orbit, with a remaining lifetime of only 5–10 Myr.