Tag Archives: paper

Kernel-phase imaging VLT/NACO paper!

In this new publication using the tools developed in the context of the KERNEL project, ANU-based PhD student Jens Kammerer announces the detection of eight low-mass companions to stars observed using VLT/NACO in the L-band, five of which were previously unknown,

Among these new companions, two appear at angular separations ranging between 0.8 and 1.2 λ/D (i.e. 80 and 110mas⁠), demonstrating that from the ground, kernel-phase makes it possible to achieve a resolution better than the traditionally accepted diffraction limit of a telescope.

Corner-plot of the best-fitting parameters for the two close companion candidates HIP50156 (top) and HIP39718 (bottom) recovered by the kernel-analysis of archival VLT/NACO L-band images.

Congratulations to Jens whose paper was accepted for publication by the Monthly Notices of the Royal Astronomical Society (MNRAS) and should appear in the June 2019 edition of the journal! The preprint version of the paper is already available for download on the arXiv.org website: https://arxiv.org/abs/1903.11252

Kernel-phase science paper accepted by A&A!

Romain Laugier, PhD student contributing to the KERNEL project, saw his first paper accepted by the journal Astronomy & Astrophysics. The paper shows how images affected by some amount of saturation can be salvaged to make them kernel-compatible again.

Using an archival HST/NICMOS dataset from 1997, Romain was able to show on a known low-mass binary that the recovery algorithm is effective. The signature of the 4.36 magnitude contrast companion, invisible in the original image, is present in the kernel-phase extracted from that image. This kernel-signature was used to constrain the position and contrast of the companion.

Saturated HST/NICMOS image of Gl 494.

This new resolved observation of the low mass companion to Gl 494 along with other recently published images, combined with a long series of archival radial velocity observations by two instruments, lead to very strong constraints on the orbital elements, and ultimately, the dynamical masses of this binary object.

Visual orbit of Gl 494 b.
Radial velocity of Gl 494 induced by the presence of the low mass companion.

Congratulations to Romain for successfully bringing this paper to the finish line: may this be the first of many others to come! The preprint version of the paper is available for download on the arXiv.org website: http://arxiv.org/abs/1901.02824