Correcting Turbulence-induced Errors in Fiber Positioning for the Dark Energy Spectroscopic Instrument

Schlafly, E. F.; Guy, J.; Honscheid, K.; Kent, S.; Koposov, S. E.; Aguilar, J.; Ahlen, S.; Bailey, S.; Brooks, D.; Claybaugh, T.; Dawson, K.; Doel, P.; Fanning, K.; Finkbeiner, D. P.; Font-Ribera, A.; Forero-Romero, J. E.; Gontcho A Gontcho, S.; Gutierrez, G.; Kirkby, D.; Kisner, T.; Kremin, A.; Landriau, M.; Lasker, J.; Le Guillou, L.; Levi, M. E.; de la Macorra, A.; Martini, P.; Meisner, A.; Miquel, R.; Moustakas, J.; Niz, G.; Prada, F.; Rossi, G.; Sanchez, E.; Schubnell, M.; Sharples, R.; Sprayberry, D.; Tarlé, G.; Weaver, B. A.; Zou, H.; DESI

Abstract

Highly multiplexed, robotic, fiber-fed spectroscopic surveys are observing tens of millions of stars and galaxies.
For many systems, accurate positioning relies on imaging the fibers in the focal plane and feeding that information
back to the robotic positioners to correct their positions. Inhomogeneities and turbulence in the air between the
focal plane and the imaging camera can affect the measured positions of fibers, limiting the accuracy with which
fibers can be placed on targets. For the Dark Energy Spectroscopic Instrument, we dramatically reduced the effect
of turbulence on measurements of positioner locations in the focal plane by taking advantage of stationary
positioners and the correlation function of the turbulence. We were able to reduce positioning errors from 7.3 to
3.5 μm, speeding the survey by 1.6% under typical conditions

Citation

Schlafly, E. F., Guy, J., Honscheid, K., Kent, S., Koposov, S. E., Aguilar, J., Ahlen, S., Bailey, S., Brooks, D., Claybaugh, T., Dawson, K., Doel, P., Fanning, K., Finkbeiner, D. P., Font-Ribera, A., Forero-Romero, J. E., Gontcho A Gontcho, S., Gutierrez, G., Kirkby, D., Kisner, T., …DESI. (2024). Correcting Turbulence-induced Errors in Fiber Positioning for the Dark Energy Spectroscopic Instrument. Astronomical Journal, 168(6), Article 263. https://doi.org/10.3847/1538-3881/ad7e12

• Journal Article Type: Article
• Acceptance Date: Sep 21, 2024
• Online Publication Date: Nov 14, 2024
• Publication Date: Dec 1, 2024
• Deposit Date: Jan 22, 2025
• Publicly Available Date: Jan 22, 2025
• Journal: The Astronomical Journal
• Print ISSN: 0004-6256
• Electronic ISSN: 1538-3881
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 168
• Issue: 6
• Article Number: 263
• DOI: https://doi.org/10.3847/1538-3881/ad7e12
• Public URL: https://durham-repository.worktribe.com/output/3346652