Marco, AmparoAmparoMarcoBernabeu, GuillermoGuillermoBernabeuNegueruela, I.I.Negueruela2020-09-172020-09-172001-04-01https://hdl.handle.net/20.500.13025/52We present uvbyβ CCD photometry of the field of the open cluster NGC 1893. Our photometry is deep enough to cover the complete main-sequence B spectral type. We identify ~50 very likely members of the cluster down to spectral type B9-A0, some of which have much higher reddenings than the average. We derive a color excess E(b-y)=0.33+/-0.03 and a dereddened distance modulus V0-MV=13.9+/-0.2. From the β index, we identify several candidates as emission-line stars, for which we have obtained spectroscopy. Three of them display spectra corresponding to spectral type F but showing Hα in emission. Photometric measurements in this and previous studies indicate strong variability. These characteristics show them to be pre-main-sequence stars of spectral type F. We also identify two likely Herbig Be stars. These results hint at the existence of a sizable pre-main-sequence population in NGC 1893.Galaxy: Open Clusters and Associations: Individual: NGC Number: NGC 1893Stars: Emission-LineBeStars: EvolutionStars: FormationStars: Pre-Main-SequenceTechniques: Photometric10.1086/319950http://adsabs.harvard.edu/abs/2001AJ....121.2075M2001AJ....121.2075M