Spectral study of V565 Mon: probable FU Ori-like or chemically peculiar star

Abstract

Abstract We present a detailed spectroscopic study of pre-main sequence star V565 Mon, which is the illuminating star of the Parsamian 17 cometary nebula. Observations were performed with the 2.6 m telescope in Byurakan Astrophysical Observatory on 2018 February 15. Radial velocities and equivalent widths of the most prominent lines of V565 Mon are presented. We build the spectral energy distribution and estimate the main parameters of the star, for example the obtained bolometric luminosity of V565 Mon is L V565 ≈ 130 L ⊙. Considering all features of V565 Mon, we come to the conclusion that this young intermediate-mass star belongs to some intermediate class between T Tau and HAeBe stars. Very unusual for a young star is the presence of strong absorption Ba II lines in the spectrum. Possible explanations on this issue are discussed. Hence, we think that V565 Mon is a unique example, which can help to understand some open questions involved in the problem of nucleosynthesis in young stars.