Search Publications

Light Elements in the Universe

Magrini, Laura; Randich, Sofia

Due to their production sites, as well as to how they are processed and destroyed in stars, the light elements are excellent tools to investigate a number of crucial issues in modern astrophysics: from stellar structure and non-standard processes at work in stellar interiors to age dating of stars; from pre-main sequence evolution to the star form…

The Census of Exoplanets in Visual Binaries: population trends from a volume-limited Gaia DR2 and literature search

Fontanive, Clémence; Bardalez Gagliuffi, Daniella

We present results from an extensive search in the literature and Gaia DR2 for visual, co-moving binary companions to stars hosting exoplanets and brown dwarfs within 200 pc. We found 218 planet hosts out of the 938 in our sample to be part of multiple-star systems, with 10 newly discovered binaries and 2 new tertiary stellar components. This repr…

Highlights of Discoveries for δ Scuti Variable Stars From the Kepler Era

Guzik, Joyce Ann

The NASAKeplerand follow-on K2 mission (2009–2018) left a legacy of data and discoveries, finding thousands of exoplanets, and also obtaining high-precision long time-series data for hundreds of thousands of stars, including many types of pulsating variables. Here we highlight a few of the ongoing discoveries fromKeplerdata on δ Scuti pulsating va…

The spiral structure in the Solar neighbourhood

Hou, L. G.

The spiral structure in the solar neighborhood is an important issue in astronomy. In the past few years, there has been significant progress in observation. The distances for a large number of good spiral tracers, i.e., giant molecular clouds, high-mass star-formation region masers, HII regions, O-type stars, and young open clusters, have been ac…

The distribution of open clusters in the Galaxy

Monteiro, Hektor; Barros, Douglas A.; Lépine, Jacques R. D. +1 more

In this work we explore the new catalog of galactic open clusters that became available recently, containing 1750 clusters that have been re-analysed using the Gaia DR2 catalog to determine the stellar memberships. We used the young open clusters as tracers of spiral arms and determined the spiral pattern rotation speed of the Galaxy and the corot…

RR Lyrae stars as seen by the Kepler space telescope

Szabó, Róbert; Plachy, Emese

The unprecedented photometric precision along with the quasi-continuous sampling provided by the Kepler space telescope revealed new and unpredicted phenomena that reformed and invigorated RR Lyrae star research. The discovery of period doubling and the wealth of low- amplitude modes enlightened the complexity of the pulsation behavior and guided …

Search for (sub)stellar companions of exoplanet hosts by exploring the second ESA-Gaia data release

Mugrauer, M.; Michel, K. -U.

We present the latest results of an ongoing multiplicity survey of exoplanet hosts, which was initiated at the Astrophysical Institute and University Observatory Jena, using data from the second data release of the ESA-Gaia mission. In this study the multiplicity of 289 targets was investigated, all located within a distance of about 500\,pc from …

Dynamics of the spiral-arm corotation and its observable footprints in the Solar Neighborhood

Pérez-Villegas, Angeles; Barros, Douglas A.; Michtchenko, Tatiana A. +1 more

This article discusses the effects of the spiral-arm corotation on the stellar dynamics in the Solar Neighborhood (SN). All our results presented here rely on: 1) observational evidence that the Sun lies near the corotation circle, where stars rotate with the same angular velocity as the spiral-arm pattern; the corotation circle establishes domain…

The Science of Fundamental Catalogs

Makarov, Valeri V.; Kopeikin, Sergei M.

This review paper discusses the science of astrometric catalogs, their current applications and future prospects for making progress in fundamental astronomy, astrophysics and gravitational physics. We discuss the concept of fundamental catalogs, their practical realizations, and future perspectives. Particular attention is paid to the astrophysic…

A comparison of the simulations and observations for a nearby spiral arm

Paunzen, Ernst; Piecka, Martin

We present a review of our current understanding of the spiral structure of galaxies, based on the kinematic models.

The analysis is focused on the ability of galactic open clusters to trace the spiral arms, based on the recent data releases from Gaia. For this, a simple 1D description of the motion of spiral arms and clusters is introduced. …