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arXiv · 2205.09014

The Robotic Multi-Object Focal Plane System of the Dark Energy Spectroscopic Instrument (DESI)

Joseph Harry Silber·Parker Fagrelius·Kevin Fanning·Michael Schubnell·Jessica Nicole Aguilar·Steven Ahlen·Jon Ameel·Otger Ballester·Charles Baltay·Chris Bebek·Dominic Benton Beard·Robert Besuner·Laia Cardiel-Sas·Ricard Casas·Francisco Javier Castander·Todd Claybaugh·Carl Dobson·Yutong Duan·Patrick Dunlop·Jerry Edelstein·William T. Emmet·Ann Elliott·Matthew Evatt·Irena Gershkovich·Julien Guy·Stu Harris·Henry Heetderks·Ian Heetderks·Klaus Honscheid·Jose Maria Illa·Patrick Jelinsky·Sharon R. Jelinsky·Jorge Jimenez·Armin Karcher·Stephen Kent·David Kirkby·Jean-Paul Kneib·Andrew Lambert·Mike Lampton·Daniela Leitner·Michael Levi·Jeremy McCauley·Aaron Meisner·Timothy N. Miller·Ramon Miquel·Juliá Mundet·Claire Poppett·David Rabinowitz·Kevin Reil·David Roman·David Schlegel·Santiago Serrano·William Van Shourt·David Sprayberry·Gregory Tarlé·Suk Sien Tie·Curtis Weaverdyck·Kai Zhang·Marco Azzaro·Stephen Bailey·Santiago Becerril·Tami Blackwell·Mohamed Bouri·David Brooks·Elizabeth Buckley-Geer·Jose Peñate Castro·Mark Derwent·Arjun Dey·Govinda Dhungana·Peter Doel·Daniel J. Eisenstein·Nasib Fahim·Juan Garcia-Bellido·Enrique Gaztañaga·Satya Gontcho A Gontcho·Gaston Gutierrez·Philipp Hörler·Robert Kehoe·Theodore Kisner·Anthony Kremin·Luzius Kronig·Martin Landriau·Laurent Le Guillou·Paul Martini·John Moustakas·Nathalie Palanque-Delabrouille·Xiyan Peng·Will Percival·Francisco Prada·Carlos Allende Prieto·Guillermo Gonzalez de Rivera·Eusebio Sanchez·Justo Sanchez·Ray Sharples·Marcelle Soares-Santos·Edward Schlafly·Benjamin Alan Weaver·Zhimin Zhou·Yaling Zhu·Hu Zou
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Abstract

A system of 5,020 robotic fiber positioners was installed in 2019 on the Mayall Telescope, at Kitt Peak National Observatory. The robots automatically re-target their optical fibers every 10 - 20 minutes, each to a precision of several microns, with a reconfiguration time less than 2 minutes. Over the next five years, they will enable the newly-constructed Dark Energy Spectroscopic Instrument (DESI) to measure the spectra of 35 million galaxies and quasars. DESI will produce the largest 3D map of the universe to date and measure the expansion history of the cosmos. In addition to the 5,020 robotic positioners and optical fibers, DESI's Focal Plane System includes 6 guide cameras, 4 wavefront cameras, 123 fiducial point sources, and a metrology camera mounted at the primary mirror. The system also includes associated structural, thermal, and electrical systems. In all, it contains over 675,000 individual parts. We discuss the design, construction, quality control, and integration of all these components. We include a summary of the key requirements, the review and acceptance process, on-sky validations of requirements, and lessons learned for future multi-object, fiber-fed spectrographs.

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Joseph Harry Silber, Parker Fagrelius, Kevin Fanning, Michael Schubnell, Jessica Nicole Aguilar, Steven Ahlen, Jon Ameel, Otger Ballester, Charles Baltay, Chris Bebek, Dominic Benton Beard, Robert Besuner, Laia Cardiel-Sas, Ricard Casas, Francisco Javier Castander, Todd Claybaugh, Carl Dobson, Yutong Duan, Patrick Dunlop, Jerry Edelstein, William T. Emmet, Ann Elliott, Matthew Evatt, Irena Gershkovich, Julien Guy, Stu Harris, Henry Heetderks, Ian Heetderks, Klaus Honscheid, Jose Maria Illa, Patrick Jelinsky, Sharon R. Jelinsky, Jorge Jimenez, Armin Karcher, Stephen Kent, David Kirkby, Jean-Paul Kneib, Andrew Lambert, Mike Lampton, Daniela Leitner, Michael Levi, Jeremy McCauley, Aaron Meisner, Timothy N. Miller, Ramon Miquel, Juliá Mundet, Claire Poppett, David Rabinowitz, Kevin Reil, David Roman, David Schlegel, Santiago Serrano, William Van Shourt, David Sprayberry, Gregory Tarlé, Suk Sien Tie, Curtis Weaverdyck, Kai Zhang, Marco Azzaro, Stephen Bailey, Santiago Becerril, Tami Blackwell, Mohamed Bouri, David Brooks, Elizabeth Buckley-Geer, Jose Peñate Castro, Mark Derwent, Arjun Dey, Govinda Dhungana, Peter Doel, Daniel J. Eisenstein, Nasib Fahim, Juan Garcia-Bellido, Enrique Gaztañaga, Satya Gontcho A Gontcho, Gaston Gutierrez, Philipp Hörler, Robert Kehoe, Theodore Kisner, Anthony Kremin, Luzius Kronig, Martin Landriau, Laurent Le Guillou, Paul Martini, John Moustakas, Nathalie Palanque-Delabrouille, Xiyan Peng, Will Percival, Francisco Prada, Carlos Allende Prieto, Guillermo Gonzalez de Rivera, Eusebio Sanchez, Justo Sanchez, Ray Sharples, Marcelle Soares-Santos, Edward Schlafly, Benjamin Alan Weaver, Zhimin Zhou, Yaling Zhu, Hu Zou. 2022-05-18. The Robotic Multi-Object Focal Plane System of the Dark Energy Spectroscopic Instrument (DESI). https://doi.org/10.3847/1538-3881/ac9ab1

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