7,990 datasets found

The Milky Way (MW) stellar halo, containing debris from past accretion events, serves as a fossil record of hierarchical mass assembly. Due to their distinct properties, RR...

Active Galactic Nuclei (AGN) are some of the brightest and most variable objects in the universe. Those with relativistic jets observed at small viewing angles are blazars. Due...

Galaxy major mergers are a potential mechanism for triggering active galactic nuclei (AGN) activity, but their role remains debated, particularly beyond the local Universe. We...

The variability mechanisms from jetted active galactic nuclei (AGNs) are still under debate. Here, the damped random walk (DRW) model, implemented through Gaussian processes...

Luminous blue variables (LBVs) exhibit unique variability features, characterized by episodic outbursts (>1mag) accompanied by spectroscopic changes (S Dor variables). It is...

In current astronomical surveys with ever-increasing data volumes, automated methods are essential. Objects of known classes from the literature are necessary to train...

A general catalogue of rotational velocities of 2558 stars has been compiled on the basis of published data. All the vsini values are reduced to the Slettebak system. The...

Blue horizontal-branch (BHB) stars are ideal tracers for mapping the structure of the Galactic stellar halo. Traditionally, BHB sample stars are built from large-scale...

We report the results of a long-duration high-cadence reverberation mapping campaign of a second batch of 11 PG quasars using the 2.2m telescope at the Calar Alto Observatory....

The Galactic global magnetic field is thought to play a vital role in shaping Galactic structures such as spiral arms and giant molecular clouds. However, our knowledge of...

We present a study of the relationship between Galactic kinematics, flare rates, chromospheric activity, and rotation periods for a volume-complete, nearly all-sky sample of 219...

AST3-2 is the second of the three Antarctic Survey Telescopes, aimed at wide-field time-domain optical astronomy. It is located at Dome A, Antarctica, which is by many measures...

We present the star formation histories (SFHs) of early-type dwarf galaxies, dSphs and dEs, in the local Universe within z = 0.01. The SFHs of early-type dwarf galaxies are...

Age is a stellar parameter that is both fundamental and difficult to determine. Among middle-aged M dwarfs, the most prolific hosts of close-in and detectable exoplanets,...

Taking advantage of ~4700 deg^2^ optical coverage of the Southern sky offered by the VST ATLAS survey, we construct a new catalogue of photometrically selected galaxy groups and...

We report an observation of the Rossiter-McLaughlin (RM) effect of the transiting planet HD 93963 Ac, a mini-Neptune planet orbiting a G0-type star with an orbital period of...

The H{alpha} nebular emission line is an optimal tracer for recent star formation in galaxies. With the advent of JWST, this line has recently become observable at z>3 for...

We performed a rigorous reverberation-mapping analysis of the broad-line region (BLR) in a highly accreting (L/L_Edd_=0.74-3.4) active galactic nucleus, Markarian 142 (Mrk 142),...

The calibration of the tip of the red giant branch (TRGB) in the I-band has a direct role in determinations of the Hubble constant, a subject of recent interest due to the...

The stellar mass Tully-Fisher relation (STFR) and its scatter encode valuable information about the processes shaping galaxy evolution across cosmic time. However, we are still...