Deep HST/STIS Coronagraphic Imaging of the β Pictoris Debris Disk: On the Scattered Light Component of the Cat's Tail
Abstract
The β Pictoris debris disk is a unique system where mid-infrared coronagraphic imaging with JWST/MIRI revealed a new spatially resolved substructure known as the Cat's Tail. We present deep HST/STIS coronagraphic imaging of β Pic in scattered light, combining six epochs of observations between 2012 and 2025, in search of the scattered light component of the Cat's Tail. We detect the disk out to a projected separation of 500 au for the first time with HST/STIS, achieving SNR > 100 across much of the midplane between 50 and 200 au. We report the detection of the visible/near-infrared scattered light component of the Cat's Tail substructure. We find through injection-recovery analysis that the scattered light component of the Cat's Tail has a total flux of 0.1−0.4% of the MIRI F1550C flux. Using the measured STIS-to-MIRI flux ratio, we model the Cat's Tail grain properties and find that the grains are highly porous and almost entirely composed of organic refractory material, which is in agreement with findings with JWST/MIRI. We use the organics content of Solar System dwarf planets and dust in the local ISM as a proxy to estimate the size of the colliding progenitors that can produce enough organic refractory material seen in the Cat's Tail. We find that each colliding progenitor must have a mass of at least 1−3× 1021 kg, comparable to Charon and Makemake in our Kuiper Belt. Additionally, we find a prominent warped morphology and surface brightness asymmetry in the outer dust halo of β Pic. We compare the observed halo morphology and asymmetry to predicted vertical structures, which may arise from planet--disk interactions.
Related
- Photometric Variability and Rotation of β Pictoris b from JWST NIRCam Coronagraphic Imaging
- Modal estimation of high-order wavefront drifts on coronagraphic testbeds for high-contrast direct imaging of exoplanets
- The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems IX: A Multi-Wavelength Framework for Source Characterization in JWST Coronagraphic Imaging of the HIP 65426 System
- Direct Imaging Discovery of Giant Exoplanet β Pictoris d: A Decade-long Game of Hide-and-seek
- A Misaligned Debris Disk relative to the Host Star CPD-72 2713 from JWST/NIRCam Imaging
BibTeX
@misc{avsar2026deep,
title = {{Deep HST/STIS Coronagraphic Imaging of the $β$ Pictoris Debris Disk: On the Scattered Light Component of the Cat's Tail}},
author = {Arin M. Avsar and Kevin Wagner and Daniel Apai and Isabel Rebollido and Antranik A. Sefilian and Marshall D. Perrin and Christopher C. Stark and Gabriel Weible and Andras Gaspar},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.30111},
eprint = {2609.30111},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.30111},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Deep HST/STIS Coronagraphic Imaging of the β Pictoris Debris Disk: On the Scattered Light Component of the Cat's Tail
AU - Arin M. Avsar
AU - Kevin Wagner
AU - Daniel Apai
AU - Isabel Rebollido
AU - Antranik A. Sefilian
AU - Marshall D. Perrin
AU - Christopher C. Stark
AU - Gabriel Weible
AU - Andras Gaspar
PY - 2026
DA - 2026/09/24
PB - arXiv
DO - 10.48550/arxiv.2609.30111
UR - https://arxiv.org/abs/2609.30111
AB - The β Pictoris debris disk is a unique system where mid-infrared coronagraphic imaging with JWST/MIRI revealed a new spatially resolved substructure known as the Cat's Tail. We present deep HST/STIS coronagraphic imaging of β Pic in scattered light, combining six epochs of observations between 2012 and 2025, in search of the scattered light component of the Cat's Tail. We detect the disk out to a projected separation of 500 au for the first time with HST/STIS, achieving SNR > 100 across much of the midplane between 50 and 200 au. We report the detection of the visible/near-infrared scattered light component of the Cat's Tail substructure. We find through injection-recovery analysis that the scattered light component of the Cat's Tail has a total flux of 0.1−0.4% of the MIRI F1550C flux. Using the measured STIS-to-MIRI flux ratio, we model the Cat's Tail grain properties and find that the grains are highly porous and almost entirely composed of organic refractory material, which is in agreement with findings with JWST/MIRI. We use the organics content of Solar System dwarf planets and dust in the local ISM as a proxy to estimate the size of the colliding progenitors that can produce enough organic refractory material seen in the Cat's Tail. We find that each colliding progenitor must have a mass of at least 1−3× 10^21 kg, comparable to Charon and Makemake in our Kuiper Belt. Additionally, we find a prominent warped morphology and surface brightness asymmetry in the outer dust halo of β Pic. We compare the observed halo morphology and asymmetry to predicted vertical structures, which may arise from planet--disk interactions.
ER -