The Roman Coronagraph Community Participation Program: Observation planning and data reduction for polarimetric mode

Ramya M Anche; Toshiyuki Mizuki; Justin Hom; Alexis Lau; Saanika Choudhary; Jaren N. Ashcraft; Clarissa Do O; Tsutsumi Nagai; Sophie Noiret; Eric Shen; Taichi Uyama; Chen Xie; Jingwen Zhang; Vanessa P. Bailey; Eric Cady; Jessica Gersh-Range; Julien H. Girard; Guillermo Gonzalez; John Livingston; Bertrand Mennesson; Maxwell A. Millar-Blanchaer; Julia Milton; Naoshi Murakami; Dmitry Savransky; Motohide Tamura; Jason J. Wang; Schuyler G. Wolff; Marie Ygouf

arXiv · 2608.17133

The Roman Coronagraph Community Participation Program: Observation planning and data reduction for polarimetric mode

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Abstract

Reflected-light polarimetry of exoplanets constrains and resolves degeneracies in atmospheric properties, while polarized light observations of debris disks enable the characterization of dust-grain properties. The best-effort polarimetric mode of the Roman Coronagraph Instrument will be able to perform multi-wavelength observations of planetary systems using both the Hybrid Lyot Coronagraph (HLC) and the Shaped Pupil Coronagraph (SPC). This paper presents an overview of observation planning, simulations, and data reduction procedures for the polarimetric mode of the Roman Coronagraph. As an initial test of simulation and data reduction, a dataset of polarimetric observing sequences for the debris disk HD 172555 in HLC mode was generated using corgisim with estimated observation parameters, and data reduction was performed using corgidrp, incorporating all relevant noise factors and calibration products. Currently, mock calibration products are used in corgidrp; these will be replaced with simulated calibration products in future updates

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Ramya M Anche, Toshiyuki Mizuki, Justin Hom, Alexis Lau, Saanika Choudhary, Jaren N. Ashcraft, Clarissa Do O, Tsutsumi Nagai, Sophie Noiret, Eric Shen, Taichi Uyama, Chen Xie, Jingwen Zhang, Vanessa P. Bailey, Eric Cady, Jessica Gersh-Range, Julien H. Girard, Guillermo Gonzalez, John Livingston, Bertrand Mennesson, Maxwell A. Millar-Blanchaer, Julia Milton, Naoshi Murakami, Dmitry Savransky, Motohide Tamura, Jason J. Wang, Schuyler G. Wolff, Marie Ygouf. 2026-08-17. The Roman Coronagraph Community Participation Program: Observation planning and data reduction for polarimetric mode. https://arxiv.org/abs/2608.17133

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