Stable Fiber-illumination for Extremely Precise Radial Velocities with NEID

Shubham Kanodia, Andrea S.J. Lin, Emily Lubar, Samuel Halverson, Suvrath Mahadevan, Chad F. Bender, Sarah E. Logsdon, Lawrence W. Ramsey, Joe P. Ninan, Gumundur Stefánsson, Andrew Monson, Christian Schwab, Arpita Roy, Leonardo A. Paredes, Eli Golub, Jesus Higuera, Jessica Klusmeyer, William McBride, Cullen Blake, Scott A. DiddamsFabien Grisé, Arvind F. Gupta, Fred Hearty, Michael W. McElwain, Jayadev Rajagopal, Paul Robertson, Ryan C. Terrien

Research output: Contribution to journalArticlepeer-review

2 Scopus citations


NEID is a high-resolution red-optical precision radial velocity (RV) spectrograph recently commissioned at the WIYN 3.5 m telescope at Kitt Peak National Observatory, Arizona, USA. NEID has an extremely stable environmental control system, and spans a wavelength range of 380-930 nm with two observing modes: a High Resolution mode at R ∼ 112,000 for maximum RV precision, and a High Efficiency mode at R ∼ 72,000 for faint targets. In this paper we present a detailed description of the components of NEID’s optical fiber feed, which include the instrument, exposure meter, calibration system, and telescope fibers. Many parts of the optical fiber feed can lead to uncalibratable RV errors, which cannot be corrected for using a stable wavelength reference source. We show how these errors directly cascade down to performance requirements on the fiber feed and the scrambling system. We detail the design, assembly, and testing of each component. Designed and built from the bottom-up with a single-visit instrument precision requirement of 27 cm s−1, close attention is paid to the error contribution from each NEID subsystem. Finally, we include the lab and on-sky tests performed during instrument commissioning to test the illumination stability, and discuss the path to achieving the instrumental stability required to search for a true Earth twin around a solar-type star.

Original languageEnglish (US)
Article number105
JournalAstronomical Journal
Issue number3
StatePublished - Sep 1 2023

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this