# Optical spectrum of the post-AGB star HD56126 in the region 4010-8790 AA

## TL;DR

This study provides a detailed high-resolution optical spectrum analysis of the post-AGB star HD56126, identifying numerous spectral features, measuring their properties, and revealing velocity variations, contributing valuable spectral data and insights into stellar atmospheres.

## Contribution

The paper presents a comprehensive spectral atlas of HD56126 with detailed measurements and analysis of spectral features, including velocity variations, which is a new detailed resource for this star.

## Key findings

- Identification of about 1500 spectral features including atoms, molecules, and interstellar bands.
- Detection of velocity variations among different spectral features and line profile changes.
- Provision of an extensive spectral atlas for HD56126 and comparison star alpha Per.

## Abstract

We studied in detail the optical spectrum of the post-AGB star HD56126 (IRAS07134+1005). We use high resolution spectra (R=25000 and 60000) obtained with the echelle spectrographs of the 6-m telescope. About one and a half thousand absorptions of neutral atoms and ions, absorption bands of C_2, CN, and CH molecules, and interstellar bands (DIBs) are identified in the 4010 to 8790 AA wavelength region, and the depths and radial velocities of these spectral features are measured. Differences are revealed between the variations of the radial velocities measured from spectral features of different excitation. In addition to the well-known variability of the Halpha profile, we found variations in the profiles of a number of FeII, YII, and BaII lines. We also produce an atlas of the spectrum of HD56126 and its comparison staralpha Per. The full version of the atlas is available in electronic form from Web-address: http://www.sao.ru/hq/ssl/Atlas/Atlas.html