150 datasets found

This catalogue includes the DDO photometry and the radial velocities observed for the study of the kinematics and abundance gradients of G and K stars in the Galactic poles...

Variability of the continuum, H{beta}, H{gamma} and HeII(4686{AA}) fluxes of the Seyfert I galaxy Mrk 509 is studied using spectra obtained on the 2.6-m telescope of the Crimean...

We investigate the morphology and kinematics of the Galactic spiral structure based on a new sample of O- and early B-type stars. We select 6858 highly confident OB star...

Classification of stars and galaxies is a well-known astronomical problem that has been treated using different approaches, most of them relying on morphological information. In...

We use the most homogeneous Geneva seven-colour photometric system to derive new metallicity calibrations for early A- to K-type stars that cover both, dwarf stars and giants....

Here we present the spectropolarimetric observations of the radio-loud active galaxy 3C 390.3 in the period 2009-2014 (24 epochs). The galaxy has been observed with the 6-m...

We present new calculations of unified line profiles for hydrogen perturbed by collisions with protons. We report on new calculations of the potential energies and dipole...

The radial velocity (RV) is a basic physical quantity that can be determined through the Doppler shift of the spectrum of a star. The precision of the RV measurement depends on...

The central region of the Virgo cluster of galaxies contains thousands of globular clusters (GCs), an order of magnitude more than the numbers found in the Local Group. Relics...

Results of a ground-based optical monitoring campaign on 3C 390.3 in 1994-1995 are presented. The broadband fluxes (B, V, R, and I), the spectrophotometric optical continuum...

The H{gamma} and H{delta} absorption features are measured in a sample of 455 (out of an original 460) Lick IDS stars with pseudo-equivalent width indices. For each Balmer...

Changing-look active galactic nucleus NGC4151, which has attracted a lot of attention, is undergoing the second dramatic outburst stage in its evolutionary history. To...

We report the discovery of a young (only 30-40Myr) snake-like structure (dubbed a stellar snake) in the solar neighborhood from Gaia DR2. The average distance of this structure...

We present a catalog of 531 white dwarf candidates that have large apparent transverse motions relative to the Sun (v_T_>200km/s), thus making them likely members of the...

In this paper, we use a machine-learning method, random forest (RF), to identify reliable members of the old (4Gyr) open cluster M67 based on the high-precision astrometry and...

We selected 4593 hot subdwarf candidates from the Gaia DR2 Hertzsprung-Russell (HR) diagram. By combining the sample with Large Sky Area Multi-Object Fibre Spectroscopic...

A sample of 102 local (0.02=<z=<0.1) Seyfert galaxies with black hole masses M_BH_>10^7^M_{sun} was selected from the Sloan Digital Sky Survey (SDSS) and observed using...

KA1858+4850 is a narrow-line Seyfert 1 galaxy at redshift 0.078 and is among the brightest active galaxies monitored by the Kepler mission. We have carried out a reverberation...

The ionizing fluxes from quasars and other active galactic nuclei (AGNs) are critical for interpreting their emission-line spectra and for photoionizing and heating the...

A small fraction of quasars have long been known to show bulk velocity offsets (of a few hundred to thousands of km/s) in the broad Balmer lines with respect to the systemic...