Design and performance of the PALM-3000 3.5 kHz upgrade

Seth R. Meeker; Tuan N. Truong; Jennifer E. Roberts; J. Chris Shelton; S. Felipe Fregoso; Rick S. Burruss; Richard G. Dekany; J. Kent Wallace; John W. Baker; Carolyn M. Heffner; Dimitri Mawet; Kevin M. Rykoski; Jonathan A. Tesch; Gautam Vasisht

arXiv · 2012.08659

Design and performance of the PALM-3000 3.5 kHz upgrade

Seth R. Meeker·Tuan N. Truong·Jennifer E. Roberts·J. Chris Shelton·S. Felipe Fregoso·Rick S. Burruss·Richard G. Dekany·J. Kent Wallace·John W. Baker·Carolyn M. Heffner·Dimitri Mawet·Kevin M. Rykoski·Jonathan A. Tesch·Gautam Vasisht

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Abstract

PALM-3000 (P3K), the second generation adaptive optics (AO) instrument for the 5.1 meter Hale telescope at Palomar Observatory, was released as a facility class instrument in October 2011 and has since been used on-sky for over 600 nights as a workhorse science instrument and testbed for coronagraph and detector development. In late 2019 P3K underwent a significant upgrade to its wavefront sensor (WFS) arm and real-time control (RTC) system to reinforce its position as a state-of-the-art AO facility and extend its faint-end capability for high-resolution imaging and precision radial velocity follow-up of Kepler and TESS targets. The main features of this upgrade include an EM-CCD WFS camera capable of 3.5 kHz framerates, and an advanced Digital signal Processor (DSP) based RTC system to replace the aging GPU based system. Similar to the pre-upgrade system, the Shack-Hartmann wavefront sensor supports multiple pupil sampling modes using a motorized lenslet stage. The default sampling mode with 64x64 subapertures has been re-commissioned on-sky in late 2019, with a successful return to science observations in November 2019. In 64x mode the upgraded system is already achieving K-band Strehl ratios up to 85% on sky and can lock on natural guide stars as faint as mV=16. A 16x16 subaperture mode is scheduled for on-sky commissioning in Fall 2020 and will extend the system's faint limit even further. Here we present the design and on-sky re-commissioning results of the upgraded system, dubbed P3K-II.

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Seth R. Meeker, Tuan N. Truong, Jennifer E. Roberts, J. Chris Shelton, S. Felipe Fregoso, Rick S. Burruss, Richard G. Dekany, J. Kent Wallace, John W. Baker, Carolyn M. Heffner, Dimitri Mawet, Kevin M. Rykoski, Jonathan A. Tesch, Gautam Vasisht. 2020-12-15. Design and performance of the PALM-3000 3.5 kHz upgrade. https://arxiv.org/abs/2012.08659

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