Identification of new classical Be stars from the LAMOST MRS survey
  Be stars are B-type main-sequence stars that display broad Balmer emission
lines in their spectra. Identification of Be population is essential to further
examine the formation and evolutionary models. We report the detection of
classical Be (CBe) stars from observations with the Large sky Area Multi-Object
fiber Spectroscopic Telescope Medium Resolution Survey of Date Release 7
(LAMOST MRS DR7). We used a deep convolutional neural network, the ResNet, with
an 18-layer module to examine the morphology of the H alpha profile. We
identified 1,162 candidate Be stars from the collection of 2,260,387 spectra
for 789,918 stars in the database. The ResNet network achieves a Be star
classification accuracy of 99.5%. Among the detections, 151 of these are prior
known Be stars cross-matched from the literature. By applying a three-step
test, we identified 183 new CBe stars. We find that 41 CBe stars are members of
known open clusters. Based upon an investigation of the kinematics of the
identified CBe stars from the Gaia EDR3 astrometric solutions, we identified 16
new runaways. These new identifications will provide a reference for future
follow-ups to further investigate their physical properties.
