Multiwavelength optical observations of two chromospherically active binary systems: V789 Mon and GZ Leo

TL;DR

This study uses multiwavelength optical observations to analyze chromospheric activity in two binary stars, determining their stellar parameters and orbital solutions to enhance understanding of activity-rotation-age relations.

Contribution

It provides detailed spectroscopic analysis and improved orbital solutions for V789 Mon and GZ Leo, including stellar parameters and chromospheric activity indicators.

Findings

Confirmed double-line binarity and improved orbital solutions.

Measured chromospheric activity indicators and stellar parameters.

Included these systems in a broader activity-rotation survey.

Abstract

This paper describes a multiwavelengh optical study of chromospheres in two X-ray/EUV selected active binary stars with strong H_alpha emission, V789 Mon (2RE J0725-002) and GZ Leo (2RE J1101+223). The goal of the study is to determine radial velocities and fundamental stellar parameters in chromospherically active binary systems in order to include them in the activity-rotation and activity-age relations. We carried out high resolution echelle spectroscopic observations and applied spectral subtraction technique in order to measure emission excesses due to chromosphere. The detailed study of activity indicators allowed us to characterize the presence of different chromospheric features in these systems and enabled to include them in a larger activity-rotation survey. We computed radial velocities of the systems using cross correlation with the radial velocity standards. The double-line spectral binarity was confirmed and the orbital solutions improved for both systems. In addition, other stellar parameters such as: spectral types, projected rotational velocities (vsini), and the equivalent width of the lithium LiI 6707.8 AA absorption line were determined.