Simulations of polarimetric observations of debris disks through the Roman Coronagraph Instrument

Abstract

The Roman coronagraph instrument will demonstrate high-contrast imaging technology, enabling the imaging of faint debris disks, the discovery of inner dust belts, and planets. Polarization studies of debris disks provide information on dust grains' size, shape, and distribution. The Roman coronagraph uses a polarization module comprising two Wollaston prism assemblies to produce four orthogonally polarized images ($I_0$, $I_{90}$, $I_{45}$, and $I_{135}$), each measuring 3.2 arcsecs in diameter and separated by 7.5 arcsecs in the sky. The expected RMS error in the linear polarization fraction measurement is 1.66\% per resolution element of 3 by 3 pixels. We present a mathematical model to simulate the polarized intensity images through the Roman CGI, including the instrumental polarization and other uncertainties. We use disk modeling software, MCFOST, to model $q$, $u$, and polarization intensity of the debris disk, Epsilon-Eridani. The polarization intensities are convolved with the coronagraph throughput incorporating the PSF morphology. We include model uncertainties, detector noise, speckle noise, and jitter. The final polarization fraction of 0.4$\pm$0.0251 is obtained after the post-processing.

arXiv comment10 pages, 11 figures, Proc. SPIE Astronomical Telescopes + Instrumentation 2022, Montreal, Canada

References in corpus (8)

• The Gemini Planet Imager: First Light
• The Signature of Primordial Grain Growth in the Polarized Light of the AU Mic Debris Disk
• Effect of dust size and structure on scattered light images of protoplanetary discs
• RoboPol: A four-channel optical imaging polarimeter
• Hubble Space Telescope Optical Imaging of the Eroding Debris Disk HD 61005
• Insights into planet formation from debris disks: II. Giant impacts in extrasolar planetary systems
• The Inner 25 AU Debris Distribution in the epsilon Eri System
• Sensitivity of the Roman Coronagraph Instrument to Exozodiacal Dust

Cited by in corpus (1)

• End-to-end numerical modeling of the Roman Space Telescope coronagraph