@article{12162,
  author = {M. Nowak and S. Lacour and A.-M. Lagrange and P. Rubini and J. Wang and T. Stolker and R. Abuter and A. Amorim and R. Asensio-Torres and M. Bauböck and Jason Dexter and et al.},
  title = {Direct confirmation of the radial-velocity planet β Pictoris c},
  abstract = {Context. Methods used to detect giant exoplanets can be broadly divided into two categories: indirect and direct. Indirect methods are more sensitive to planets with a small orbital period, whereas direct detection is more sensitive to planets orbiting at a large distance from their host star. This dichotomy makes it difficult to combine the two techniques on a single target at once.

Aims. Simultaneous measurements made by direct and indirect techniques offer the possibility of determining the mass and luminosity of planets and a method of testing formation models. Here, we aim to show how long-baseline interferometric observations guided by radial-velocity can be used in such a way.

Methods. We observed the recently-discovered giant planet β Pictoris c with GRAVITY, mounted on the Very Large Telescope Interferometer.

Results. This study constitutes the first direct confirmation of a planet discovered through radial velocity. We find that the planet has a temperature of T = 1250 ± 50 K and a dynamical mass of M = 8.2 ± 0.8 MJup. At 18.5 ± 2.5 Myr, this puts β Pic c close to a ‘hot start’ track, which is usually associated with formation via disk instability. Conversely, the planet orbits at a distance of 2.7 au, which is too close for disk instability to occur. The low apparent magnitude (MK = 14.3 ± 0.1) favours a core accretion scenario.

Conclusions. We suggest that this apparent contradiction is a sign of hot core accretion, for example, due to the mass of the planetary core or the existence of a high-temperature accretion shock during formation.},
  year = {2020},
  journal = {Astronomy & Astrophysics},
  volume = {642},
  pages = {L2},
  month = {2020-10},
  publisher = {EDP Sciences},
  issn = {1432-0746},
  url = {http://dx.doi.org/10.1051/0004-6361/202039039},
  doi = {10.1051/0004-6361/202039039},
}