Paper: Overview of the Instrumentation for the Dark Energy Spectroscopic Instrument
Authors: DESI Collaboration, B. Abareshi, J. Aguilar, S. Ahlen, Shadab Alam, David M. Alexander, R. Alfarsy, L. Allen, C. Allende Prieto, O. Alves, J. Ameel, E. Armengaud, J. Asorey, Alejandro Aviles, S. Bailey, A. Balaguera-Antolínez, O. Ballester, C. Baltay, A. Bault, S. F. Beltran, B. Benavides, S. BenZvi, A. Berti, R. Besuner, Florian Beutler, D. Bianchi, C. Blake, P. Blanc, R. Blum, A. Bolton, S. Bose, D. Bramall, S. Brieden, A. Brodzeller, D. Brooks, C. Brownewell, E. Buckley-Geer, R. N. Cahn, Z. Cai, R. Canning, R. Capasso, A. Carnero Rosell, P. Carton, R. Casas, F. J. Castander, J. L. Cervantes-Cota, S. Chabanier, E. Chaussidon, C. Chuang, C. Circosta, S. Cole, A. P. Cooper, L. da Costa, M.-C. Cousinou, A. Cuceu, T. M. Davis, K. Dawson, R. de la Cruz-Noriega, A. de la Macorra, A. de Mattia, J. Della Costa, P. Demmer, M. Derwent, A. Dey, B. Dey, G. Dhungana, Z. Ding, C. Dobson, P. Doel, J. Donald-McCann, J. Donaldson, K. Douglass, Y. Duan, P. Dunlop, J. Edelstein, S. Eftekharzadeh, D. J. Eisenstein, M. Enriquez-Vargas, S. Escoffier, M. Evatt, P. Fagrelius, X. Fan, K. Fanning, V. A. Fawcett, S. Ferraro, J. Ereza, B. Flaugher, A. Font-Ribera, J. E. Forero-Romero, C. S. Frenk, S. Fromenteau, B. T. Gänsicke, C. Garcia-Quintero, L. Garrison, E. Gaztañaga, F. Gerardi, H. Gil-Marín, S. Gontcho A Gontcho, Alma X. Gonzalez-Morales, G. Gonzalez-de-Rivera, V. Gonzalez-Perez, C. Gordon, O. Graur, D. Green, C. Grove, D. Gruen, G. Gutierrez, J. Guy, C. Hahn, S. Harris, D. Herrera, Hiram K. Herrera-Alcantar, K. Honscheid, C. Howlett, D. Huterer, V. Iršič, M. Ishak, P. Jelinsky, L. Jiang, J. Jimenez, Y. P. Jing, R. Joyce, E. Jullo, S. Juneau, N. G. Karaçaylı, M. Karamanis, A. Karcher, T. Karim, R. Kehoe, S. Kent, D. Kirkby, T. Kisner, F. Kitaura, S. E. Koposov, A. Kovács, A. Kremin, Alex Krolewski, B. L'Huillier, O. Lahav, A. Lambert, C. Lamman, Ting-Wen Lan, M. Landriau, S. Lane, D. Lang, J. U. Lange, J. Lasker, L. Le Guillou, A. Leauthaud, A. Le Van Suu, Michael E. Levi, T. S. Li, C. Magneville, M. Manera, Christopher J. Manser, B. Marshall, Paul Martini, W. McCollam, P. McDonald, Aaron M. Meisner, J. Mena-Fernández, J. Meneses-Rizo, M. Mezcua, T. Miller, R. Miquel, P. Montero-Camacho, J. Moon, J. Moustakas, E. Mueller, Andrea Muñoz-Gutiérrez, Adam D. Myers, S. Nadathur, J. Najita, L. Napolitano, E. Neilsen, Jeffrey A. Newman, J. D. Nie, Y. Ning, G. Niz, P. Norberg, Hernán E. Noriega, T. O'Brien, A. Obuljen, N. Palanque-Delabrouille, A. Palmese, P. Zhiwei, D. Pappalardo, X. PENG, W. J. Percival, S. Perruchot, R. Pogge, C. Poppett, A. Porredon, F. Prada, J. Prochaska, R. Pucha, A. Pérez-Fernández, I. Pérez-Ràfols, D. Rabinowitz, A. Raichoor, S. Ramirez-Solano, César Ramírez-Pérez, C. Ravoux, K. Reil, M. Rezaie, A. Rocher, C. Rockosi, N. A. Roe, A. Roodman, A. J. Ross, G. Rossi, R. Ruggeri, V. Ruhlmann-Kleider, C. G. Sabiu, S. Gaines, K. Said, A. Saintonge, Javier Salas Catonga, L. Samushia, E. Sanchez, C. Saulder, E. Schaan, E. Schlafly, D. Schlegel, J. Schmoll, D. Scholte, M. Schubnell, A. Secroun, H. Seo, S. Serrano, Ray M. Sharples, Michael J. Sholl, Joseph Harry Silber, D. R. Silva, M. Sirk, M. Siudek, A. Smith, D. Sprayberry, R. Staten, B. Stupak, T. Tan, Gregory Tarlé, Suk Sien Tie, R. Tojeiro, L. A. Ureña-López, F. Valdes, O. Valenzuela, M. Valluri, M. Vargas-Magaña, L. Verde, M. Walther, B. Wang, M. S. Wang, B. A. Weaver, C. Weaverdyck, R. Wechsler, Michael J. Wilson, J. Yang, Y. Yu, S. Yuan, Christophe Yèche, H. Zhang, K. Zhang, Cheng Zhao, Rongpu Zhou, Zhimin Zhou, H. Zou, J. Zou, S. Zou, Y. Zu
Figure caption: Results of a fiber dither test on 2021 December 19. (Left) The four, smaller panels show the offset of each fiber positioner from the best-fit position determined by the dither test. The four panels show the offsets in R.A. and decl. for all positioners (top left), the distribution of offsets in decl. (right) and R.A. (bottom left), and the total offset (bottom right). The total offset corresponds to the amplitude of the decenter of each positioner, and in this case the width of the distribution is 0.″16, and the procedure is sensitive to offsets smaller than 0.″05. (Right) Amplitude and direction of the offsets in focal plane coordinates. The primarily radial pattern may indicate a residual error in the distortion model. An offset of 40 μm is indicated by the arrow in the upper-left corner; for context, we note that the fiber diameter is 107 μm and the plate scale is approximately 70 μm per arcsecond. This field was observed near zenith at an altitude of 81.°4, and the direction of zenith is indicated in the lower-right corner. The fluxes in the fibers at each dither position are from the red channel of the spectrographs.