Millimeter Dust Emission in the GQ Lup System

TL;DR

This study uses submillimeter observations to analyze the dust emission around GQ Lup A, revealing a compact disk with a mass of about 3 Jupiter masses, and finds no evidence of a disk around GQ Lup B or signs of additional companions.

Contribution

First high-resolution submillimeter imaging of the GQ Lup system, constraining the disk properties around GQ Lup A and assessing the formation scenario of GQ Lup B.

Findings

Detected emission from GQ Lup A's disk, marginally resolved.

No emission detected from GQ Lup B, indicating absence of a substantial disk.

Disks around GQ Lup A are likely truncated and less massive than needed for in situ formation of GQ Lup B.

Abstract

We present Submillimeter Array observations of the GQ Lup system at 1.3 millimeters wavelength with $0\farcs4$ ($\sim$60 AU) resolution. Emission is detected from the position of the primary star, GQ Lup A, and is marginally resolved. No emission is detected from the substellar companion, GQ Lup B, $0\farcs7$ away. These data, together with models of the spectral energy distribution, suggest a compact disk around GQ Lup A with mass $\sim 3$ M$_{Jup}$, perhaps truncated by tidal forces. There is no evidence for a gap or hole in the disk that might be the signature of an additional inner companion body capable of scattering GQ Lup B out to $\sim100$ AU separation from GQ Lup A. For GQ Lup B to have formed {\it in situ}, the disk would have to have been much more massive and extended.