We present a sample of 48 metal-poor galaxies at z < 0.14 selected from 92,510 galaxies in the LAMOST survey .
These galaxies are identified for their detection of the auroral emission line [ O iii ] \lambda 4363 above 3 \sigma level , which allows a direct measurement of the electron temperature and the oxygen abundance .
The emission line fluxes are corrected for internal dust extinction using Balmer decrement method .
With electron temperature derived from [ O iii ] \lambda \lambda 4959 , 5007 / \hbox { [ O { \sc iii } ] } \lambda 4363 and electron density from \hbox { [ S { \sc ii } ] } \lambda 6731 / \hbox { [ S { \sc ii } ] } \lambda 6717 , we obtain the oxygen abundances in our sample which range from \hbox { $ 12 + { log ( O / H ) } $ } = 7.63 ( 0.09 { Z } _ { \sun } ) to 8.46 ( 0.6 { Z } _ { \sun } ) .
We find an extremely metal-poor galaxy with \hbox { $ 12 + { log ( O / H ) } $ } = 7.63 \pm 0.01 .
With multiband photometric data from FUV to NIR and H \alpha measurements , we also determine the stellar masses and star formation rates , based on the spectral energy distribution fitting and H \alpha luminosity , respectively .
We find that our galaxies have low and intermediate stellar masses with 6.39 \leq log ( M / M _ { \sun } ) \leq 9.27 , and high star formation rates ( SFRs ) with -2.18 \leq log ( SFR / M _ { \sun } yr ^ { -1 } ) \leq 1.95 .
We also find that the metallicities of our galaxies are consistent with the local T _ { e } -based mass-metallicity relation , while the scatter is about 0.28 dex .
Additionally , assuming the coefficient of \alpha = 0.66 , we find most of our galaxies follow the local mass-metallicity-SFR relation , while a scatter about 0.24 dex exists , suggesting the mass-metallicity relation is weakly dependent on SFR for those metal-poor galaxies .