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The Slitmask Alignment Tool: robust, efficient, and astronomer-friendly software for aligning multi-object slitmasks

Kassis, Marc and Wirth, Gregory D. and Phillips, Andrew C. and Steidel, Charles C. (2012) The Slitmask Alignment Tool: robust, efficient, and astronomer-friendly software for aligning multi-object slitmasks. In: Observatory Operations: Strategies, Processes, and Systems IV. Proceedings of SPIE. No.8448. Society of Photo-Optical Instrumentation Engineers (SPIE) , Bellingham, WA, Art. No. 844807. ISBN 9780819491497.

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Multi-object spectroscopy via custom slitmasks is a key capability on three instruments at the W. M. Keck Observatory. Before observers can acquire spectra they must complete a complex procedure to align each slit with its corresponding science target. We developed the Slitmask Alignment Tool (SAT), to replace a complex, inefficient, and error-prone slitmask alignment process that often resulted in lost sky time for novice and experienced observers alike. The SAT accomplishes rapid initial mask alignment, prevents field misidentification, accurately predicts alignment box image locations, corrects for flexure-induced image displacement, verifies the instrument and exposure configuration, and accommodates both rectangular and trapezoidal alignment box shapes. The SAT is designed to lead observers through the alignment process and coordinate image acquisition with instrument and telescope moves to improve efficiencies. By simplifying the process to just a few mouse clicks, the SAT enables even novice observers to achieve robust, efficient, and accurate alignment of slitmasks on all three Keck instruments supporting multislit spectroscopy, saving substantial observing time.

Item Type:Book Section
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Steidel, Charles C.0000-0002-4834-7260
Additional Information:© 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The Observatory would like to acknowledge Gordon and Betty Moore for their generous support of the MOSFIRE instrument. This material is based in part upon work supported by AURA through the National Science Foundation under AURA Cooperative Agreement AST-0132798, as amended. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.
Funding AgencyGrant Number
W. M. Keck FoundationUNSPECIFIED
Gordon and Betty Moore FoundationUNSPECIFIED
Subject Keywords:multislit spectroscopy, slitmask alignment, observing tools, on-sky efficiencies, W. M. Keck Observatory
Series Name:Proceedings of SPIE
Issue or Number:8448
Record Number:CaltechAUTHORS:20161021-121520878
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Official Citation:Marc Kassis ; Gregory D. Wirth ; Andrew C. Phillips and Charles C. Steidel " The slitmask alignment tool: robust, efficient, and astronomer-friendly software for aligning multi-object slitmasks ", Proc. SPIE 8448, Observatory Operations: Strategies, Processes, and Systems IV, 844807 (September 13, 2012); doi:10.1117/12.926693;
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:71346
Deposited By: George Porter
Deposited On:21 Oct 2016 19:39
Last Modified:03 Oct 2019 16:06

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