# Constraints on a Putative Planet Sculpting the V4046 Sagittarii Circumbinary Disk

## TL;DR

This study uses high-resolution ALMA and NIR imaging to analyze the structure of the V4046 Sgr circumbinary disk, suggesting a Jovian-mass planet influences its features and discussing disk longevity in a binary system.

## Contribution

First detailed high-resolution millimeter and NIR imaging analysis of V4046 Sgr's circumbinary disk, combined with disk-planet interaction simulations to constrain potential planet mass.

## Key findings

- Detected a ~32 au dust ring with ~90 au extension.
- Identified a tentative inner dust ring at ~14 au.
- Simulations suggest a Jovian-mass planet may shape the disk structures.

## Abstract

We analyze the highest-resolution millimeter continuum and near-infrared (NIR) scattered-light images presented to date of the circumbinary disk orbiting V4046 Sgr, a ~20 Myr old actively accreting, close binary T Tauri star system located a mere 72.4 pc from Earth. We observed the disk with the Atacama Large Millimeter/submillimeter Array (ALMA) at 870-micron during Cycle 4, and we analyze these data in conjunction with archival NIR (H band) polarimetric images obtained with SPHERE/IRDIS on the ESO Very Large Telescope. At 0.3'' (20 au) resolution, the 870-micron image reveals a marginally resolved ring that peaks at ~32 au and has an extension of ~ 90 au. We infer a lower limit on dust mass of ~ 60.0 M_earth within the 870-micron ring, and confirm that the ring is well aligned with the larger-scale gaseous disk. A second, inner dust ring is also tentatively detected in the ALMA observations; its position appears coincident with the inner (~14 au radius) ring detected in scattered light. Using synthetic 870 micron and H-band images obtained from disk-planet interaction simulations, we attempt to constrain the mass of the putative planet orbiting at 20 au. Our trials suggest that a circumbinary Jovian-mass planet may be responsible for generating the dust ring and gap structures detected within the disk. We discuss the longevity of the gas-rich disk orbiting V4046 Sgr in the context of the binary nature of the system.