Searching for Be Stars in the Open Cluster NGC 663
  We present Be star candidates in the open cluster NGC\,663, identified by
H$\alpha$ imaging photometry with the Palomar Transient Factory Survey, as a
pilot program to investigate how the Be star phenomena, the emission spectra,
extended circumstellar envelopes, and fast rotation, correlate with massive
stellar evolution. Stellar membership of the candidates was verified by 2MASS
magnitudes and colors, and by proper motions. We discover 4 new Be stars and
exclude one known Be star from being a member due to its inconsistent proper
motions. The fraction of Be stars to member stars [N(Be)/N(members)] in
NGC\,663 is 3.5\%. The spectral type of the 34 Be stars in NGC\,663 shows
bimodal peaks at B0--B2 and B5--B7, which is consistent with the statistics in
most star clusters. Additionally, we also discover 23 emission-line stars of
different types, including non-member Be stars, dwarfs, and giants.
