Correction Factors of the Measurement Errors of the LAMOST-LRS Stellar Parameters

Abstract We aim to investigate the propriety of stellar parameter errors official data release LAMOST low-resolution spectroscopy (LRS) survey. diagnose radial velocity (RV), atmospheric parameters ([Fe/H], T eff , log g ) and α -enhancement ([ /M]) for latest version DR7, including 6,079,235 effective spectra 4,546,803 stars. Based on duplicate observational sample comparing deviation multiple measurements their given errors, we find that, in general, error [ /M] is largely underestimated, RV slightly overestimated. define a correction factor k quantify these misestimations correct be expressed as proper internal uncertainties. Using this self-calibration technique, that -factors significantly vary with spectral types signal-to-noise ratio (S/N). Particularly, reveal strange but evident trend between themselves all five parameters. Larger tend have smaller -factor values, i.e., they were more After correction, recreate tight correlations S/N parameters, while dependence types. It also suggests from each spectrum should corrected individually. Finally, provide factors derived entire LAMOST-LRS DR7 plan update them later releases.