Keck Planet Finder: preliminary design

Gibson, Steven R.; Howard, Andrew W.; Roy, Arpita; Smith, Christopher L.; Halverson, Samuel; Edelstein, Jerry; Kassis, Marc; Wishnow, Edward H.; Raffanti, Michael; Allen, S. L.; Chin, Jason C. Y.; Coutts, David W.; Cowley, David J.; Curtis, James M.; Deich, William T. S.; Feger, Tobias; Finstad, D.; Gurevich, Yulia V.; Ishikawa, Yuzo; James, Ean; Jhoti, E.; Lanclos, Kyle; Lilley, Scott; Miller, Tim; Milner, Steve; Payne, Thomas J.; Rider, Kodi; Rockosi, Constance M.; Sandford, Dale; Schwab, Christian; Seifahrt, Andreas; Sirk, Martin M.; Smith, Roger; Stuermer, Julian; Weisfeiler, Marie; Wilcox, Mavourneen K.; Vandenberg, Adam; Wizinowich, Peter

doi:10.1117/12.2311565

Cited by 10 publications

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Staring at the Sun with the Keck Planet Finder: An Autonomous Solar Calibrator for High Signal-to-noise Sun-as-a-star Spectra

Rubenzahl,

Halverson,

Walawender

et al. 2023

PASP

View full text Add to dashboard Cite

Extreme precision radial velocity (EPRV) measurements contend with internal noise (instrumental systematics) and external noise (intrinsic stellar variability) on the road to 10 cm s−1 “exo-Earth” sensitivity. Both of these noise sources are well-probed using “Sun-as-a-star” RVs and cross-instrument comparisons. We built the Solar Calibrator (SoCal), an autonomous system that feeds stable, disk-integrated sunlight to the recently commissioned Keck Planet Finder (KPF) at the W. M. Keck Observatory. With SoCal, KPF acquires signal-to-noise ratio (S/N) ∼ 1200, R = 98,000 optical (445–870 nm) spectra of the Sun in 5 s exposures at unprecedented cadence for an EPRV facility using KPF’s fast readout mode (<16 s between exposures). Daily autonomous operation is achieved by defining an operations loop using state machine logic. Data affected by clouds are automatically flagged using a reliable quality control metric derived from simultaneous irradiance measurements. Comparing solar data across the growing global network of EPRV spectrographs with solar feeds will allow EPRV teams to disentangle internal and external noise sources and benchmark spectrograph performance. To facilitate this, all SoCal data products are immediately available to the public on the Keck Observatory Archive. We compared SoCal RVs to contemporaneous RVs from NEID, the only other immediately public EPRV solar data set. We find agreement at the 30–40 cm s−1 level on timescales of several hours, which is comparable to the combined photon-limited precision. Data from SoCal were also used to assess a detector problem and wavelength calibration inaccuracies associated with KPF during early operations. Long-term SoCal operations will collect upwards of 1000 solar spectra per six-hour day using KPF’s fast readout mode, enabling stellar activity studies at high S/N on our nearest solar-type star.

show abstract

Staring at the Sun with the Keck Planet Finder: An Autonomous Solar Calibrator for High Signal-to-noise Sun-as-a-star Spectra

Rubenzahl,

Halverson,

Walawender

et al. 2023

PASP

View full text Add to dashboard Cite

show abstract

On-sky commissioning of MAROON-X: a new precision radial velocity spectrograph for Gemini North

Seifahrt

Bean

Stürmer

et al. 2020

Ground-Based and Airborne Instrumentation for Astronomy VIII

View full text Add to dashboard Cite

MAROON-X is a fiber-fed, red-optical, high precision radial velocity spectrograph recently commissioned at the Gemini North telescope on Mauna Kea, Hawai'i. With a resolving power of 85,000 and a wavelength coverage of 500-920 nm, it delivers radial velocity measurements for late K and M dwarfs with sub-50 cm s −1 precision. MAROON-X is currently the only optical EPRV spectrograph on a 8 m-class telescope in the northern hemisphere and the only EPRV instrument on a large telescope with full access by the entire US community. We report here on the results of the commissioning campaign in December 2019 and early science results.

show abstract

Solar Contamination in Extreme-precision Radial-velocity Measurements: Deleterious Effects and Prospects for Mitigation

Roy

Halverson

Mahadevan

et al. 2020

Self Cite

View full text Add to dashboard Cite

Solar contamination, due to moonlight and atmospheric scattering of sunlight, can cause systematic errors in stellar radial velocity (RV) measurements that significantly detract from the ∼10 cm s −1 sensitivity required for the detection and characterization of terrestrial exoplanets in or near Habitable Zones of Sun-like stars. The addition of low-level spectral contamination at variable effective velocity offsets introduces systematic noise when measuring velocities using classical mask-based or template-based cross-correlation techniques. Here we present simulations estimating the range of RV measurement error induced by uncorrected scattered sunlight contamination. We explore potential correction techniques, using both simultaneous spectrometer sky fibers and broadband imaging via coherent fiber imaging bundles, that could reliably reduce this source of error to below the photon-noise limit of typical stellar observations. We discuss the limitations of these simulations, the underlying assumptions, and mitigation mechanisms. We also present and discuss the components designed and built into the NEID precision RV instrument for the WIYN 3.5m telescope, to serve as an ongoing resource for the community to explore and evaluate correction techniques. We emphasize that while "bright time" has been traditionally adequate for RV science, the goal of 10 cm s −1 precision, on the most interesting exoplanetary systems may necessitate access to darker skies for these next-generation instruments.

show abstract

Keck Planet Finder: preliminary design

Cited by 10 publications

References 40 publications

Staring at the Sun with the Keck Planet Finder: An Autonomous Solar Calibrator for High Signal-to-noise Sun-as-a-star Spectra

Staring at the Sun with the Keck Planet Finder: An Autonomous Solar Calibrator for High Signal-to-noise Sun-as-a-star Spectra

On-sky commissioning of MAROON-X: a new precision radial velocity spectrograph for Gemini North

Solar Contamination in Extreme-precision Radial-velocity Measurements: Deleterious Effects and Prospects for Mitigation

Contact Info

Product

Resources

About