GPI 2.0: Upgrades to the IFS including new spectral modes

Mary Anne Limbach; Jeffrey Chilcote; Quinn Konopacky; Robert De Rosa; Randall Hamper; Bruce Macintosh; Christian Marois; Marshall Perrin; Dmitry Savransky; Jean-Pierre Veran; Jason Wang; Arlene Aleman

arXiv · 2012.00792

GPI 2.0: Upgrades to the IFS including new spectral modes

Mary Anne Limbach·Jeffrey Chilcote·Quinn Konopacky·Robert De Rosa·Randall Hamper·Bruce Macintosh·Christian Marois·Marshall Perrin·Dmitry Savransky·Jean-Pierre Veran·Jason Wang·Arlene Aleman

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Abstract

The Gemini Planet Imager (GPI) is a high-contrast imaging instrument designed to directly image and characterize exoplanets. GPI is currently undergoing several upgrades to improve performance. In this paper, we discuss the upgrades to the GPI IFS. This primarily focuses on the design and performance improvements of new prisms and filters. This includes an improved high-resolution prism which will provide more evenly dispersed spectra across y, J, H and K-bands. Additionally, we discuss the design and implementation of a new low-resolution mode and prism which allow for imaging of all four bands (y, J, H and K-bands) simultaneously at R=10. We explore the possibility of using a multiband filter which would block the light between the four spectral bands. We discuss possible performance improvements from the multiband filter, if implemented. Finally we explore the possibility of making small changes to the optical design to improve the IFS's performance near the edge of the field of view.

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Mary Anne Limbach, Jeffrey Chilcote, Quinn Konopacky, Robert De Rosa, Randall Hamper, Bruce Macintosh, Christian Marois, Marshall Perrin, Dmitry Savransky, Jean-Pierre Veran, Jason Wang, Arlene Aleman. 2020-12-01. GPI 2.0: Upgrades to the IFS including new spectral modes. https://arxiv.org/abs/2012.00792

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