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arXiv · 1703.09937

The eShel Spectrograph: A Radial-velocity Tool at the Wise Observatory

Michael Engel·Sahar Shahaf·Tsevi Mazeh
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Abstract

The eShel, an off-the-shelf, fiber-fed echelle spectrograph ($R \approx 10,000$), was installed on the 1m telescope at the Wise observatory in Israel. We report the installation of the multi-order spectrograph, and describe our pipeline to extract stellar radial velocity from the obtained spectra. We also introduce a new algorithm---UNICOR, to remove radial-velocity systematics that can appear in some of the observed orders. We show that the system performance is close to the photon-noise limit for exposures with more than $10^7$ counts, with a precision that can get better than 200 m/s for F--K stars, for which the eShel spectral response is optimal. This makes the eShel at Wise a useful tool for studying spectroscopic binaries brighter than $m_V=11$. We demonstrate this capability with orbital solutions of two binaries from projects being performed at Wise.

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Michael Engel, Sahar Shahaf, Tsevi Mazeh. 2017-03-29. The eShel Spectrograph: A Radial-velocity Tool at the Wise Observatory. https://doi.org/10.1088/1538-3873%2Faa65c6

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