Related papers: Galactic O-type stars in LAMOST data

We report the discovery of fifteen previously unknown Wolf-Rayet (WR) stars found as part of an infrared broad-band study of candidate WR stars in the Galaxy. We have derived an empirically-based selection algorithm which has selected ~5000…

Detailed studies of Be stars in environments with different metallicities like the Magellanic Clouds or the Galactic bulge are necessary to understand the formation and evolution mechanisms of the circumstellar disks. However, a detailed…

Metal-poor stars are a rare and ancient type of stars; Carbon-Enhanced Metal-Poor (CEMP) stars are a subset of these celestial bodies that show an enrichment of carbon relative to iron. They are believed to be formed from gas polluted by…

An MK-like spectral classification has been conducted for 1224 hot subdwarf stars with LAMOST DR9 low-resolution spectra. The whole sample was divided into four categories according to the spectral line characteristics: He-normal, He-weak,…

We report the discovery of 11 OH megamasers and one OH absorber, along with upper limits on the OH luminosity of 53 other luminous infrared galaxies at z > 0.1. The new megamasers show a wide range of spectral properties, but are consistent…

We present a collection of classical, type II, and anomalous Cepheids detected in the OGLE fields toward the Galactic center. The sample contains 87 classical Cepheids pulsating in one, two or three radial modes, 924 type II Cepheids…

The goal of this paper is to present and analyse a new sample of cool carbon (C)stars located in the halo. Twenty three new C stars were discovered. Spectra are typical of N-type stars with C2 and CN bands and sometimes Halpha in emission.…

This study utilized LAMOST low-resolution spectra to identify M-type YSOs and characterize their accretion signatures. We measured characteristic features, including hydrogen Balmer, Li {\sc i}, He~{\sc i}, Na {\sc i}, and Ca {\sc ii}…

We present a new spectroscopic classification for OB stars based on H-band (1.5 micron to 1.8 micron) observations of a sample of stars with optical spectral types. Our initial sample of nine stars demonstrates that the combination of He I…

We present the results of optical spectroscopic observations of 54 candidate evolved massive stars revealed through the detection of mid-infrared nebulae of various shapes surrounding them with the {\it Spitzer Space Telescope} and {\it…

Tsinghua University-Ma Huateng Telescopes for Survey (TMTS), located at Xinglong Station of NAOC, has a field of view upto 18 deg^2. The TMTS has started to monitor the LAMOST sky areas since 2020, with the uninterrupted observations…

We have detected 13 new runaway-star candidates of spectral type O combining the TGAS (Tycho-Gaia Astrometric Solution) proper motions from Gaia Data Release 1 (DR1) and the sample from GOSSS (Galactic O-Star Spectroscopic Survey). We have…

Initial results, techniques, and rationale for a near-infrared survey of evolved emission-line stars toward the Galactic Center are presented. We use images taken through narrow-band emission-line and continuum filters to select candidates…

In the second part of the OGLE-III Catalog of Variable Stars (OIII-CVS) we present 197 type II Cepheids and 83 anomalous Cepheids in the Large Magellanic Cloud (LMC). The sample of type II Cepheids consists of 64 BL Her stars, 96 W Vir…

We report on early results from a pilot program searching for metal-poor stars with LAMOST and follow-up high-resolution observation acquired with the MIKE spectrograph attached to the Magellan~II telescope. We performed detailed abundance…

CONTEXT. Many O-type stars have nearby companions whose presence hamper their characterization through spectroscopy. AIMS. We want to obtain spatially resolved spectroscopy of close O-type visual binaries to derive their spectral types.…

Many transiting planet host stars lack high resolution imaging and thus close stellar sources can be missed. Those unknown stars potentially bias the derivation of the planetary and stellar parameters from the transit light curve, no matter…

A total of 194 isotopes with 11 $\le$ Z $\le$ 19 have been identified to date. The discovery of these isotopes which includes the observation of unbound nuclei, is discussed. For each isotope a brief summary of the first refereed…

Spectroscopic observations of various tracers in nearby galaxies, such as Andromeda (M31), play a crucial role in identifying and classifying individual stellar populations and nebular objects, thereby enhancing our understanding of…

We present a support vector machine classifier to identify the K giant stars from the LAMOST survey directly using their spectral line features. The completeness of the identification is about 75% for tests based on LAMOST stellar…