Spectroscopic Study of the High-latitude far Evolved Star V534 Lyr

TL;DR

This study analyzes the spectral properties of the post-AGB star V534 Lyr using high-resolution spectra to determine its atmospheric parameters, chemical composition, and kinematic properties, revealing it is a high-velocity, metal-poor star outside the galactic disk.

Contribution

First detailed spectroscopic analysis of V534 Lyr providing atmospheric parameters, chemical abundances, and kinematic classification for this post-AGB star.

Findings

V534 Lyr has T_eff = 10500 K and log g = 2.5.

The star shows an underabundance of iron group elements ([Met/H] = -0.50).

V534 Lyr is a high-velocity, metal-poor star not belonging to the galactic disk.

Abstract

We study a pulsating variable post-AGB star V534 Lyr = HD172324 based on five high resolution spectra (R = 60 000) obtained with the NES echelle spectrograph of the 6--meter Russian telescope (BTA) in 2010 and 2013. Using the atmosphere modeling method and the Kurucz model set, we obtained the effective temperature T$_{\rm eff}$ = 10500 K, surface gravity log g = 2.5, and microturbulent velocity ${\rm \xi_t}$=4.0 km/s. The underabundance of the iron group elements ${\rm [Met/H]_{\odot} = -0.50}$ was detected. This fact in combination with high spatial velocity indicates that V534 Lyr does not belong to the disk population. The radial velocity gradient in the V534 Lyr atmosphere is minimum: differential shifts of lines are close to measurement errors The spectral class A0 Iab corresponds to the distance to V534 Lyr, d$\approx$6 kpc.