New symbiotic stars or candidates in LAMOST low resolution spectra

TL;DR

This study identifies 36 potential symbiotic stars from LAMOST low-resolution spectra, including five new confirmed systems, advancing the understanding of binary star interactions and progenitors of Type Ia supernovae.

Contribution

The paper introduces a novel method for detecting symbiotic stars using LAMOST spectral features and Gaia data, discovering five new confirmed symbiotic systems.

Findings

Identified 36 symbiotic star candidates from LAMOST data.

Confirmed five new symbiotic stars, including two recent discoveries.

Proposed classification criteria based on emission line features.

Abstract

Symbiotic stars are among the most crucial binary systems for studying binary star interactions and Type Ia supernova progenitors. Based on the unique observational characteristics of symbiotic stars, strong H I, He I emission lines, giant spectral features, and the presence of [O III], He II, O VI, and other emission lines with ionization potentials exceeding 35 eV, and the Gaia information, we search for new symbiotic stars using the low-resolution spectroscopic survey data from LAMOST. Thirty-six binary systems have been selected as symbiotic stars or candidates, in which the five known symbiotic stars are included. Among them five systems (ZTF J005917.52+315605.4, ATO J094137.5+075304, LAMOST J200310.90+360822.6, LAMOST J072528.18+342530.4, and V* V758 Cyg) have been found as new symbiotic stars. Notably, LAMOST J072528.18+342530.4 and V* V758 Cyg were also confirmed as new symbiotic stars in a recent study. For the remaining 26 candidates, classification is based solely on the presence of [O III] emission lines (with ionization potentials > 35 eV) and the absence of He II high-excitation emission lines. Further observations are needed to confirm their nature as symbiotic stars.