Investigation of the inner structures around HD169142 with VLT/SPHERE

TL;DR

This study uses VLT/SPHERE observations to analyze the inner structures of the HD169142 system, revealing that previously identified blobs are part of a bright ring, and detecting additional structures near the star.

Contribution

It provides new high-resolution imaging data clarifying the nature of inner structures around HD169142, distinguishing between potential planets and ring features.

Findings

Bright blobs are part of a ring at 180 mas

Detection of a bright structure at 93 mas possibly a companion

Marginal detection of an inner ring at 100 mas

Abstract

We present observations of the Herbig Ae star HD169142 with VLT/SPHERE instruments InfraRed Dual-band Imager and Spectrograph (IRDIS) ($K1K2$ and $H2H3$ bands) and the Integral Field Spectrograph (IFS) ($Y$, $J$ and $H$ bands). We detect several bright blobs at $\sim$180 mas separation from the star, and a faint arc-like structure in the IFS data. Our reference differential imaging (RDI) data analysis also finds a bright ring at the same separation. We show, using a simulation based on polarized light data, that these blobs are actually part of the ring at 180 mas. These results demonstrate that the earlier detections of blobs in the $H$ and $K_S$ bands at these separations in Biller et al. as potential planet/substellar companions are actually tracing a bright ring with a Keplerian motion. Moreover, we detect in the images an additional bright structure at $\sim$93 mas separation and position angle of 355$^{\circ}$, at a location very close to previous detections. It appears point-like in the $YJ$ and $K$ bands but is more extended in the $H$ band. We also marginally detect an inner ring in the RDI data at $\sim$100 mas. Follow-up observations are necessary to confirm the detection and the nature of this source and structure.