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Title: GPI 2.0: exploring the impact of different readout modes on the wavefront sensor's EMCCD
The Gemini Planet Imager (GPI) is a high contrast imaging instrument that aims to detect and characterize extrasolar planets. GPI is being upgraded to GPI 2.0, with several subsystems receiving a re-design to improve its contrast. To enable observations on fainter targets and increase performance on brighter ones, one of the upgrades is to the adaptive optics system. The current Shack-Hartmann wavefront sensor (WFS) is being replaced by a pyramid WFS with an low-noise electron multiplying CCD (EMCCD). EMCCDs are detectors capable of counting single photon events at high speed and high sensitivity. In this work, we characterize the performance of the HNu ̈ 240 EMCCD from Nuvu Cameras, which was custom-built for GPI 2.0. Through our performance evaluation we found that the operating mode of the camera had to be changed from inverted-mode (IMO) to non-inverted mode (NIMO) in order to improve charge diffusion features found in the detector’s images. Here, we characterize the EMCCD’s noise contributors (readout noise, clock-induced charges, dark current) and linearity tests (EM gain, exposure time) before and after the switch to NIMO.  more » « less
Award ID(s):
2046883
PAR ID:
10599910
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; « less
Editor(s):
Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J
Publisher / Repository:
SPIE
Date Published:
ISBN:
9781510675179
Page Range / eLocation ID:
293
Format(s):
Medium: X
Location:
Yokohama, Japan
Sponsoring Org:
National Science Foundation
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