Reanalysis of two eclipsing binaries: EE Aqr and Z Vul

TL;DR

This paper reanalyzes the radial-velocity and light curves of the eclipsing binaries EE Aqr and Z Vul using the Wilson & Van Hamme model, determining their absolute parameters and filling factors.

Contribution

It provides updated absolute parameters and fill-out proportions for EE Aqr and Z Vul, classifying their evolutionary states with a modern model.

Findings

EE Aqr is a near-contact system with the primary filling 96% of its Roche lobe.

Z Vul is a semi-detached system with the secondary filling 100% of its Roche lobe.

Results are compared with previous studies to refine system parameters.

Abstract

We study the radial-velocity and light curves of the two eclipsing binaries EE Aqr and Z Vul. Using the latest version of the Wilson & Van Hamme (2003) model, absolute parameters for the systems are determined. We find that EE Aqr and Z Vul are near-contact and semi-detached systems, respectively. The primary component of EE Aqr fills about 96% of its 'Roche lobe', while its secondary one appears close to completely filling this limiting volume. In a similar way, we find fill-out proportions of about 72 and 100% of these volumes for the primary and secondary components of Z Vul respectively. We compare our results with those of previous authors.