AO Vel: The role of multiplicity in the development of chemical peculiarities in late B-type stars

TL;DR

This study analyzes a quadruple B-type star system, revealing that all components are chemically peculiar with distinct abundance patterns, and suggests multiplicity influences chemical peculiarities in such stars.

Contribution

It provides the first detailed spectral analysis of all four stars in AO Vel, linking multiplicity to chemical peculiarities in late B-type stars.

Findings

All four stars are chemically peculiar with unique abundance patterns.

The two less massive stars are HgMn stars.

The more massive stars show chemical spots and variability.

Abstract

We present high-resolution, high signal-to-noise UVES spectra of AO Vel, a quadruple system containing an eclipsing BpSi star. From these observations we reconstruct the spectra of the individual components and perform an abundance analysis of all four stellar members. We found that all components are chemically peculiar with different abundances patters. In particular, the two less massive stars show typical characteristics of HgMn stars. The two most massive stars in the system show variable line profiles indicating the presence of chemical spots. Given the youth of the system and the notable chemical peculiarities of their components, this system could give important insights in the origin of chemical anomalies.