The Robotic Multiobject Focal Plane System of the Dark Energy Spectroscopic Instrument (DESI)
J. Silber, Parker Fagrelius, Kevin Fanning, M. Schubnell, J. Aguilar, S. P. Ahlen, Jon Ameel, O. Ballester, C. Baltay, C. Bebek, D. Beard, Robert Besuner, L. Cardiel, R. Casas, F. J. Castander, T. Claybaugh, C. A. Dobson, Yutong Duan, Psm Dunlop, Jerry Edelstein, W. Emmet, Ann Elliott, Matthew Evatt, Irena Gershkovich, J. Guy, Stu Harris, Henry Heetderks, Ian Heetderks, K. Honscheid, J. M. Illa, Patrick Jelinsky, Sharon R. Jelinsky, Jorge Jiménez, Armin Karcher, S. Kent, D. Kirkby, Jean‐Paul Kneib, Andrew Lambert, M. Lampton, Daniela Leitner, M. E. Levi, Jeremy McCauley, Aaron Meisner, Timothy N. Miller, R. Miquel, Juliá Mundet, Claire Poppett, D. Rabinowitz, K. Reil, David Roman, David J. Schlegel, S. Serrano, William Van Shourt, David Sprayberry, G. Tarlé, Suk Sien Tie, Curtis Weaverdyck, Kai Zhang, M. Azzaro, S. Bailey, S. Becerril, Tami Blackwell, Mohamed Bouri, D. Brooks, E. Buckley‐Geer, José Peñate Castro, Mark Derwent, Arjun Dey, G. Dhungana, P. Doel, Daniel J. Eisenstein, Nasib Fahim, J. García-Bellido, E. Gaztañaga, Satya Gontcho A Gontcho, G. Gutiérrez, Philipp Hörler, R. Kehoe, Theodore Kisner, Anthony Kremin, Luzius Kronig, Martin Landriau, L. Le Guillou, Paul Martini, John Moustakas, N. Palanque‐Delabrouille, Xiyan Peng, Will J. Percival, Francisco Prada, Carlos Allende Prieto, Guillermo Glez-de-Rivera, E. Sánchez, Justo Sánchez, R. M. Sharples, M. Soares-Santos, Edward F. Schlafly, Benjamin A. Weaver, Zhimin Zhou, Yaling Zhu, Hu Zou
Abstract
Abstract A system of 5020 robotic fiber positioners was installed in 2019 on the Mayall Telescope, at Kitt Peak National Observatory. The robots automatically retarget their optical fibers every 10–20 minutes, each to a precision of several microns, with a reconfiguration time of fewer than 2 minutes. Over the next 5 yr, 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 5020 robotic positioners and optical fibers, DESI’s Focal Plane System includes six guide cameras, four wave front 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 multiobject, fiber-fed spectrographs.