Re-visiting the seismic properties of the PMS -Scuti star V346Ori

In order to test Pre Main-Sequence (PMS) evolutionary models, one needs to compare model evolutionary tracks with the position of several PMS stars in the H-R diagram. Accurate stellar luminosities, effective temperatures and masses are needed for such comparisons to be conclusive. A way of obtaining these parameters relies on the use of asteroseismological techniques in pulsating PMS stars.
V346 Ori, classified as a PMS Herbig Ae star, is found to lie inside the PMS instability strip identified by Marconi & Palla (1998) and hence it is a good candidate to display brightness oscillations due to pulsation. We have previously reported the discovery of periodicities in V346 Ori's light curve and identified two oscillation frequencies (Pinheiro et al 2002). The false alarm probabilities associated with those frequencies still gave margin for a reasonable doubt to be cast on their identification, though.
Based on new observations of V346 Ori, we now present a development in the study of the brightness variations in this star. In particular we confirm beyond doubt the existence of the two frequencies alluded to above, and possibly the existence of at least another two frequencies in the star's lightcurve. We discuss these results in the context of the radial oscillations in PMS stars.

 
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