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arXiv · 2211.09279

A Decade of Linear and Circular Polarimetry with the POLISH2 Polarimeter

Sloane J. Wiktorowicz·Agnieszka Słowikowska·Larissa A. Nofi·Nicole Rider·Angie Wolfgang·Ninos Hermis·Daniel Jontof-Hutter·Amanda J. Bayless·Gary M. Cole·Kirk B. Crawford·Valeri V. Tsarev·Michael C. Owens·Ernest G. Jaramillo·Geoffrey A. Maul·James R. Graham·Maxwell A. Millar-Blanchaer·Kimberly Bott·Jon C. Mauerhan
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Abstract

The POLISH2 optical polarimeter has been in operation at the Lick Observatory 3-m Shane telescope since 2011, and it was commissioned at the Gemini North 8-m in 2016. This instrument primarily targets exoplanets, asteroids, and the Crab pulsar, but it has also been used for a wide variety of planetary, galactic, and supernova science. POLISH2's photoelastic modulators, employed instead of rotating waveplates or ferro-electric liquid crystal modulators, offer the unprecedented ability to achieve sensitivity and accuracy of order 1 ppm (0.0001%), which are difficult to obtain with conventional polarimeters. Additionally, POLISH2 simultaneously measures intensity (Stokes I), linear polarization (Stokes Q and U), and circular polarization (Stokes V), which fully describe the polarization state of incident light. We document our laboratory and on-sky calibration methodology, our archival on-sky database, and we demonstrate conclusive detection of circular polarization of certain objects.

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Sloane J. Wiktorowicz, Agnieszka Słowikowska, Larissa A. Nofi, Nicole Rider, Angie Wolfgang, Ninos Hermis, Daniel Jontof-Hutter, Amanda J. Bayless, Gary M. Cole, Kirk B. Crawford, Valeri V. Tsarev, Michael C. Owens, Ernest G. Jaramillo, Geoffrey A. Maul, James R. Graham, Maxwell A. Millar-Blanchaer, Kimberly Bott, Jon C. Mauerhan. 2022-11-17. A Decade of Linear and Circular Polarimetry with the POLISH2 Polarimeter. https://doi.org/10.3847/1538-4365/aca407

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