Dracula’s Chivito: Discovery of a Large Edge-on Protoplanetary Disk with Pan-STARRS

Abstract

We report the serendipitous discovery of a large edge-on protoplanetary disk in Pan-STARRS (PS1) images. PS1 has five broadband filters designated as g _P1 , r _P1 , i _P1 , z _P1 , and y _P1 with mean wavelengths 4866, 6215, 7545, 8679, and 9633 Å, respectively. The disk’s apparent size in the PS1 images is ≈11″, making this one of the largest known disks on the sky. It is likely a young system, still surrounded by the envelope, which is very faint but still visible in the PS1 images in the northern part (alternatively this structure could be filaments from the disk itself). We use the PS1 magnitudes and other available photometric data to construct the spectral energy distribution of the disk. An optical spectrum indicates that the obscured star is hot, most likely of type late A. We adopt a distance of 300 pc for this object based on Gaia Data Release 3 extinctions. We model the system using the HOCHUNK3D radiative transfer software and find that the system is consistent with a hot star of effective temperature 8000 K surrounded by a disk of size 1650 au and mass 0.2 M _⊙ at inclination 82°.

Keywords

• Stellar accretion disks
• Circumstellar matter
• Radiative transfer
• Pre-main sequence stars