Oscillations in the PMS δ Scuti star V346 Ori^*

¹ Centro de Astrofísica da Universidade do Porto, Rua das Estrelas, 4150–762 Porto, Portugal
² INAF-Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy
³ INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
⁴ Departamento de Matemática Aplicada, Faculdade de Ciências da Universidade do Porto, Portugal
⁵ INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, 40127 Bologna, Italy
⁶ Departamento de Astrofísica, Universidad de La Laguna, Avda. Astrofísico F. Sánchez s/n, Campus de Anchieta, 38206 La Laguna, Spain

Corresponding author: D. F. M.  Folha, dfmf@astro.up.pt

Received: 16 September 2002
Accepted: 27 November 2002

Abstract

We report the discovery of periodicities in the light curve of the Pre-Main Sequence (PMS) Herbig Ae star V346 Ori. We interpret variations in the light curve of the star as the superposition of at least two periodic signals that result from δ Scuti-type stellar oscillations. The computation of linear non-adiabatic radial pulsation models for PMS stars reproduces these periods for a 1.55  star with  K and log pulsating in the fundamental and in the second overtone. If our assumption of radial oscillations is indeed correct, the star's location on the HR diagram places it at a distance significantly smaller than that of the Orion star forming region, hence raising questions regarding the evolutionary status of V346 Ori. Observations with better time sampling and spanning a longer period of time are needed if the latter question is to be addressed fully.