A catalog of more than 43,000 M giant stars has been selected by Li et al.from the ninth data release of LAMOST.Using the data-driven method SLAM,we obtain the stellar parameters(T_(eff),logg,[M/H],[α/M])for all the ...A catalog of more than 43,000 M giant stars has been selected by Li et al.from the ninth data release of LAMOST.Using the data-driven method SLAM,we obtain the stellar parameters(T_(eff),logg,[M/H],[α/M])for all the M giant stars with uncertainties of 57 K,0.25 dex,0.16 dex and 0.06 dex at SNR>100,respectively.With those stellar parameters,we constrain the absolute magnitude in the K-band,which brings distance with relative uncertainties around 25%statistically.Radial velocities are also calculated by applying cross correlation on the spectra between 8000 and 8950?with synthetic spectra from ATLAS9,which covers the CaⅡtriplet.Comparison between our radial velocities and those from APOGEE DR17 and Gaia DR3 shows that our radial velocities have a system offset and dispersion around 1 and 4.6 km s^(-1),respectively.With the distances and radial velocities combining with the astrometric data from Gaia DR3,we calculate the full 6D position and velocity information,which are able to be used for further chemo-dynamic studies on the disk and substructures in the halo,especially the Sagittarius Stream.展开更多
基金supported by Beijing Natural Science Foundation with Grant No.1214028the National Natural Science Foundation of China(NSFC)under grant 12103062+7 种基金the NSFC under grant 12273027the NSFC under Grant Nos.12090040,12090044,and 11833006the NSFC with grant No.11835057support from the NSFC(Grant No.12133002)China West Normal University grant 17YC507.the National Key R&D Program of China No.2019YFA0405501supported by the National Key R&D Program of China No.2019YFA0405502Guo Shou Jing Telescope(the Large sky Area Multi-Object fiber Spectroscopic Telescope LAMOST)is a National Major Scientific Project built by the Chinese Academy of Sciences.Funding for the project has been provided by the National Development and Reform Commission。
文摘A catalog of more than 43,000 M giant stars has been selected by Li et al.from the ninth data release of LAMOST.Using the data-driven method SLAM,we obtain the stellar parameters(T_(eff),logg,[M/H],[α/M])for all the M giant stars with uncertainties of 57 K,0.25 dex,0.16 dex and 0.06 dex at SNR>100,respectively.With those stellar parameters,we constrain the absolute magnitude in the K-band,which brings distance with relative uncertainties around 25%statistically.Radial velocities are also calculated by applying cross correlation on the spectra between 8000 and 8950?with synthetic spectra from ATLAS9,which covers the CaⅡtriplet.Comparison between our radial velocities and those from APOGEE DR17 and Gaia DR3 shows that our radial velocities have a system offset and dispersion around 1 and 4.6 km s^(-1),respectively.With the distances and radial velocities combining with the astrometric data from Gaia DR3,we calculate the full 6D position and velocity information,which are able to be used for further chemo-dynamic studies on the disk and substructures in the halo,especially the Sagittarius Stream.
