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Based on high resolution and high signal-to-noise ratio (S/N) spectra analysis of 90 solar type stars, we have established several new metallicity calibrations in Teff range [5600, 6500] K based on red spectra with the wavelength range of 560-880 nm. The new metallicity calibrations are applied to determine the metallicity of solar analogs selected from SDSS spectra. There is a good consistent result with the adopted value presented in SDSS-DR7 and a small scatter of 0.26 dex for stars with S/N > 50 is obtained. This study provides a new reliable way to derive the metallicity for solar-like stars with low resolution spectra. In particular, our calibrations are useful for finding metal-rich stars, which are missing in SSPP.
Several recent studies of Solar twins in the Solar neighbourhood have shown a tight correlation between various elemental abundances and age, in particular [Y/Mg]. If this relation is real and valid for other types of stars as well as elsewhere in th
When recording spectra from the ground, atmospheric turbulence causes degradation of the spatial resolution. We present a data reduction method that restores the spatial resolution of the spectra to their undegraded state. By assuming that the point
Our study aims to recognize M-type stars which are classified as UNKNOWN due to bad quality in Large sky Area Multi-Object fibre Spectroscopic Telescope (LAMOST) DR5 V1. A binary nonlinear hashing algorithm based on Multi-Layer Pseudo Inverse Learnin
In the near future we will have ground- and space-based telescopes that are designed to observe and characterize Earth-like planets. While attention is focused on exoplanets orbiting main sequence stars, more than 150 exoplanets have already been det
While the near-infrared wavelength regime is becoming more and more important for astrophysics there is a marked lack of spectrophotometric standard star data that would allow the flux calibration of such data. Furthermore, flux calibrating medium- t