The VAMPIRES instrument: Imaging the innermost regions of protoplanetary disks with polarimetric interferometry

TL;DR

VAMPIRES is a novel polarimetric interferometry instrument that enables direct imaging of the innermost regions of protoplanetary disks at the diffraction limit, providing new insights into planet formation processes.

Contribution

This paper introduces VAMPIRES, a new instrument combining aperture-masking interferometry with polarimetry for high-resolution imaging of protoplanetary disk regions.

Findings

Successful on-sky commissioning demonstrating high visibility and closure phase precision.

Validated the instrument's capability to image regions close to the diffraction limit.

Projected science performance metrics based on initial observations.

Abstract

Direct imaging of protoplanetary disks promises to provide key insight into the complex sequence of processes by which planets are formed. However imaging the innermost region of such disks (a zone critical to planet formation) is challenging for traditional observational techniques (such as near-IR imaging and coronagraphy) due to the relatively long wavelengths involved and the area occulted by the coronagraphic mask. Here we introduce a new instrument -- VAMPIRES -- which combines non-redundant aperture-masking interferometry with differential polarimetry to directly image this previously inaccessible innermost region. By using the polarisation of light scattered by dust in the disk to provide precise differential calibration of interferometric visibilities and closure phases, VAMPIRES allows direct imaging at and beyond the telescope diffraction limit. Integrated into the SCExAO system at the Subaru telescope, VAMPIRES operates at visible wavelengths (where polarisation is high) while allowing simultaneous infrared observations conducted by HICIAO. Here we describe the instrumental design and unique observing technique and present the results of the first on-sky commissioning observations, validating the excellent visibility and closure phase precision which are then used to project expected science performance metrics.