Optical spectroscopy of DPVs and the case of LP Ara

TL;DR

This paper reports preliminary spectroscopic observations of Double Periodic Variables, a class of interacting binaries with unique long-term cycles, providing insights into their mass transfer processes and presenting a detailed case study of LP Ara.

Contribution

It offers the first spectroscopic analysis of DPVs and models the LP Ara system, enhancing understanding of their mass flow dynamics and long-term variability.

Findings

High-resolution line profiles reveal mass flows in DPVs.

A detailed model of LP Ara's orbital light curve and radial velocities.

Evidence supporting mass loss cycles in DPVs.

Abstract

We present preliminary results of our spectroscopic campaign of a group of intermediate mass interacting binaries dubbed "Double Periodic Variables" (DPVs), characterized by orbital light curves and additional long photometric cycles recurring roughly after 33 orbital periods (Mennickent et al. 2003, 2005). They have been interpreted as interacting, semi-detached binaries showing cycles of mass loss into the interstellar medium (Mennickent et al. 2008, Mennickent & Kolaczkowski 2009). High resolution Balmer and helium line profiles of DPVs can be interpreted in terms of mass flows in these systems. A system solution is given for LP Ara, based on modeling of the ASAS V-band orbital light curve and the radial velocity of the donor star.