Properties of Radial Velocities Measurement Based on LAMOST-II Medium-resolution Spectroscopic Observations
R. Wang, A.-L. Luo, J.-J. Chen, Z.-R. Bai, L. Chen, X.-F. Chen, S.-B. Dong, B. Du, J.-N. Fu, Z.-W. Han, J.-L. Hou, Y.-H. Hou
(+19 others)
2019
Astrophysical Journal Supplement Series
The radial velocity (RV) is a basic physical quantity which can be determined through Doppler shift of the spectrum of a star. The precision of RV measurement depends on the resolution of the spectrum we used and the accuracy of wavelength calibration. In this work, radial velocities of LAMOST-II medium resolution (R ~ 7500) spectra are measured for 1,594,956 spectra (each spectrum has two wavebands) through matching with templates. A set of RV standard stars are used to recalibrate the zero
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... nt of the measurement, and some reference sets with RVs derived from medium/high-resolution observations are used to evaluate the accuracy of the measurement. Comparing with reference sets, the accuracy of our measurement can get 0.0227 km s/1 with respect to radial velocities standard stars. The intrinsic precision is estimated with the multiple observations of single stars, which can achieve to 1.36 km s/1,1.08 km s/1, 0.91 km s/1 for the spectra at signal-to-noise levels of 10, 20, 50, respectively.
doi:10.3847/1538-4365/ab3cc0
fatcat:v64dxpxj3vea7i2vzvpz74vime
