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arXiv · 0806.3749

A Pathfinder Instrument for Precision Radial Velocities in the Near-Infrared

L. W. Ramsey·J. Barnes·S. L. Redman·H. R. A. Jones·A. Wolszczan·S. Bongiorno·L. Engel·J. Jenkins
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Abstract

We have designed and tested an in-plane echelle spectrograph configured to investigate precision radial velocities from ground-based near-infrared observations. The spectrograph operates across the spectral range of 0.9-1.7 mm at a spectral resolution of R = 50,000, and uses a liquid nitrogen-cooled HAWAII 1K detector. Repeated measurements of the Earth's rotation via integrated Sunlight with two different instrument arrangements in the near infrared Y band have produced radial velocities with ~10 m/s RMS over a period of several hours. The most recent instrument configuration has achieved an unbinned RMS of 7 m/s and suggests that infrared radial velocity precisions may be able to approach those achieved at optical wavelengths.

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L. W. Ramsey, J. Barnes, S. L. Redman, H. R. A. Jones, A. Wolszczan, S. Bongiorno, L. Engel, J. Jenkins. 2008-06-23. A Pathfinder Instrument for Precision Radial Velocities in the Near-Infrared. https://doi.org/10.1086/591233

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