1,087 datasets found

In this study we carry out detailed spectral classification of 173 AGN candidates from the Joint HRC/BHRC sample, which is a combination of HRC (Hamburg-ROSAT Catalogue) and...

The spectral-double system escaping from multiple system theta1 Ori C is investigated. Radial velocities of both components are measured, for them are constructed and solved...

We apply the variational autoencoder (VAE) to the LAMOST-K2 low-resolution spectra to detect the magnetic activity of the stars in the K2 field. After the training on the...

Eta Carinae is a massive interacting binary system shrouded in a complex circumstellar environment whose evolution is the source of the long-term brightening observed during the...

We present an investigation of the interdependence of the optical-to-X-ray spectral slope (aox), the HeII equivalent-width (EW), and the monochromatic luminosity at 2500{AA}...

We study the projected spatial offset between the ultraviolet continuum and Lya emission for 65 lensed and unlensed galaxies in the Epoch of Reionization 5<=z<=7, the...

This paper presents a survey of MgII absorbing gas in the vicinity of 380 random galaxies, using 156 background quasi-stellar objects (QSOs) as absorption-line probes. The...

We present here quantitative diagnostic tools for cool giants that employ low-resolution near-infrared spectroscopy in the K band for stellar population studies. In this study,...

In this study, we analyse the emission lines of different species present in 118 Galactic field classical Be stars in the wavelength range of 3800-9000{AA}. We re-estimated the...

We present a study of the metal-enriched cool halo gas traced by MgII absorption around 228 galaxies at z~0.8-1.5 within 28 quasar fields from the MUSE Analysis of Gas around...

We analyse two-dimensional maps and radial profiles of EW(H{alpha}), EW(H{delta}A), and D_n_(4000) of low-redshift galaxies using integral field spectroscopy from the MaNGA...

We report on H-band spectra of chemically peculiar Mercury-Manganese (HgMn) stars obtained via the SDSS/APOGEE survey. As opposed to other varieties of chemically peculiar stars...

We present a line-by-line differential analysis of a sample of 16 planet-hosting stars and 68 comparison stars using high-resolution, high signal-to-noise ratio spectra gathered...

We present the results from a systematic study of temporal variation of stellar activity in young late-type stars. We used multi-epoch LAMOST (Large sky Area Multi-Object fiber...

Stellar magnetic activity is an interesting phenomenon in late-type stars. We use the medium-resolution spectroscopic observations of 406069 late-type stars from LAMOST to...

In the last three decades several hundred nearby members of young stellar moving groups (MGs) have been identified, but there has been less systematic effort to quantify or...

MEGARA (Multi Espectrografo en GTC de Alta Resolucion para Astronomia) is an optical (3650-9750{AA}), fibre-fed, medium-high spectral resolution (R=6000, 12000 and 20000)...

We present here medium resolution ({lambda}/{Delta}{lambda}~1200) H- and K-band spectra of M-type dwarf stars covering the wavelength ranges 1.50-1.80{mu}m and 1.95-2.45{mu}m....

This work presents a spectroscopic study of 163 Herbig Ae/Be stars. Amongst these, we present new data for 30 objects. Stellar parameters such as temperature, reddening, mass,...

We present Chandra observations of 2106 radio-quiet quasars in the redshift range 1.7<=z<=2.7 from the Sloan Digital Sky Survey (SDSS), through data release fourteen...