Blue irregular variable stars in the Small Magellanic Cloud from EROS2: Herbig Ae/Be or classical Be stars?

Using data from the EROS2 microlensing survey, we report the discovery of t wo blue objects with irregular photometric behaviour of DeltaV similar to 0 .1-0.4 mag on time scales of 20 to 200 days. They show a bluer when fainter behaviour. Subsequent spectra taken with the ESO 3.6 m telescope show spec tral type B4eIII and B2eIV-V with strong H alpha emission. These objects re semble the Herbig AeBe but also classical Be stars. At this stage, it is no t possible to distinguish unambiguously between pre-main sequence and class ical Be nature. If we favour the pre-main sequence interpretation, they are more luminous than the luminosity upper limit for Galactic HAeBe stars. Th e same was found for the HAeBe candidates in the LMC. This might be due to a shorter accretion time scale (tau = M-*/M), or the smaller dust content d uring the pre-main sequence evolution of SMC and LMC stars. Further studies on a larger scale of the environment and IR properties of the stars are ne eded.