CHAUVIN , Gaël

Direct imaging is the primary technique currently used to detect young and warm exoplanets and understand their formation scenarios. The extreme flux r atio b etween a n e xoplanet a nd i ts h ost s tar r equires t he u se of coronagraphs to attenuate the starlight and create high contrast images. However, their performance is limited by...

Context. Emission lines that are indicative of active accretion have been observed for a number of low-mass companions (M < 30 MJup) to stars. Line variability is ubiquitous on stellar accretors, but it has never been characterized in detail for low-mass companions. Such characterizations can offer insights into the accretion mechanism at...

Recent observations by the B-star Exoplanet Abundance Study (BEAST) illustrate the existence of substellar companions around very massive stars. Here, we present the detection of two lower mass companions to a relatively nearby (148.7 −1.3 +1.5 pc), young (17 −4 +3 Myr), bright ( V = 6.632 ± 0.006 mag), 2.58 ± 0.06 M ⊙ B9V star HIP 81208...

We present simultaneous 0.65-2.5 m medium resolution (3300 R 8100) VLT/X-shooter spectra of the relatively young (150-300 Myr) low-mass (19 5MJup) L-T transition object VHS 1256-1257 b, a known spectroscopic analog of HR8799d. The companion is a prime target for the JWST Early Release Science (ERS) and one of the highest-Amplitude variable...