Search Publications

The near-infrared companion to HD 94660 (=KQ Vel)
DOI: 10.1051/0004-6361/202038950 Bibcode: 2020A&A...642A.188S

Hubrig, S.; Robrade, J.; Hummel, C. A. +4 more

Context. The Bp star HD 94660 is a single-lined spectroscopic binary. Some authors have suggested that the unseen companion of at least 2 M may be a compact object.
Aims: We intend to study this multiple system in detail, especially to learn more about the thus far unseen companion.
Methods: We have collected and analyzed PIO…

2020 Astronomy and Astrophysics
Gaia 4
The Quadruple System HIP 45734
DOI: 10.3847/1538-3881/ab6a13 Bibcode: 2020AJ....159...88T

Tokovinin, Andrei

HIP 45734 is a quadruple system of 2 + 2 architecture located at 68 pc from the Sun. The outer 9″ system A,B has a period of ∼104 yr. The subsystem Aa,Ab is a visual binary with a period of 20.1 yr and an eccentricity of 0.78. Its periastron in 2019.1 was observed spectroscopically, yielding masses (1.10 ± 0.04 and 0.98 ± 0.03 ${{ \math…

2020 The Astronomical Journal
Gaia 4
X-ray Flux and Spectral Variability of Blazar H 2356-309
DOI: 10.3390/galaxies8030059 Bibcode: 2020Galax...8...59W

Gaur, Haritma; Wani, Kiran A.

We present the results of timing and spectral analysis of the blazar H 2356-309 using XMM-Newton observations. This blazar is observed during 13 June 2005–24 December 2013 in total nine observations. Five of the observations show moderate flux variability with amplitude 1.7–2.2%. We search for the intra-day variability timescales in these five lig…

2020 Galaxies
XMM-Newton 4
Contribution of polar plumes to fast solar wind
DOI: 10.1051/0004-6361/202037653 Bibcode: 2020A&A...643A.104Z

Zangrilli, L.; Giordano, S. M.

Context. Several physical properties of solar polar plumes have been identified by different published studies, however such studies are rare and sometimes in disagreement.
Aims: The purpose of the present work is to analyze a set of SOHO/UVCS data dedicated to the observation of plumes and to obtain a picture of the physical properties of pl…

2020 Astronomy and Astrophysics
SOHO 4
The hot limit of solar-like oscillations from Kepler photometry
DOI: 10.3389/fspas.2020.529025 Bibcode: 2020FrASS...7...85B

Balona, Luis A.

Kepler short-cadence photometry of 2347 stars with effective temperatures in the range 6000 - 10000 K was used to search for the presence of solar-like oscillations. The aim is to establish the location of the hot end of the stochastic convective excitation mechanism and to what extent it may overlap the δ Scuti/γ Doradus instability region. A sim…

2020 Frontiers in Astronomy and Space Sciences
Gaia 4
On the Pulsations of the δ Scuti Star of the Binary System KIC 6629588
DOI: 10.32023/0001-5237/70.4.2 Bibcode: 2020AcA....70..265L

Liakos, A.

This work includes a comprehensive analysis of the Kepler detached eclipsing binary system KIC 6629588 that aims at the detailed study of the oscillation properties of its pulsating component. Ground-based spectroscopic observations were obtained and used to classify the components of the system. The spectroscopic results were used as constraints …

2020 Acta Astronomica
Gaia 4
Nonlinear Color-Metallicity Relations of Globular Clusters. IX. Different Radial Number Density Profiles between Blue and Red Clusters
DOI: 10.3847/1538-4357/abc4e9 Bibcode: 2020ApJ...905..124L

Chung, Chul; Lee, Sang-Yoon; Yoon, Suk-Jin

The optical colors of globular clusters (GCs) in most large early-type galaxies are bimodal. Blue and red GCs show a sharp difference in the radial profile of their surface number density in the sense that red GCs are more centrally concentrated than blue GCs. An instant interpretation is that there exist two distinct GC subsystems having differen…

2020 The Astrophysical Journal
eHST 4
Estimating the Ages of FGK Dwarf Stars through the Use of GALEX FUV Magnitudes
DOI: 10.3847/1538-3881/abb77d Bibcode: 2020AJ....160..217C

Crandall, Sara; Smith, Graeme H.; Subramonian, Arjun +2 more

Stellar age cannot be directly measured, yet age determinations are fundamental to understanding the evolution of stars, planets, and galaxies. The work presented here builds upon the idea of a stellar-activity age. We utilized far-ultraviolet (FUV) photometry acquired by the Galaxy Evolution Explorer (GALEX) space telescope as an indicator of chr…

2020 The Astronomical Journal
IUE 4
VLT/SPHERE survey for exoplanets around young early-type stars, including systems with multi-belt architectures
DOI: 10.1051/0004-6361/202037961 Bibcode: 2020A&A...639A..54L

Minniti, D.; Bayo, A.; Girard, J. +21 more

Context. Dusty debris disks around pre- and main-sequence stars are potential signposts for the existence of planetesimals and exoplanets. Giant planet formation is therefore expected to play a key role in the evolution of the disk. This is indirectly confirmed by extant submillimeter near-infrared images of young protoplanetary and cool dusty deb…

2020 Astronomy and Astrophysics
Gaia 4
Frontal Aureole Deposit on Acheron Fossae ridge as evidence for landslide-generated tsunami on Mars
DOI: 10.1016/j.pss.2020.104911 Bibcode: 2020P&SS..18704911D

De Blasio, Fabio Vittorio

The recurrent failures of the 8 to 10-km high basal scarp of the Olympus Mons volcano on Mars has resulted in enormous landslides merging into a composite deposit known as the aureole. The largest of these landslides, the western (W) aureole, appears as a hummocky and extensive tongue reaching the distance of 700 km from the present Olympus Mons e…

2020 Planetary and Space Science
MEx 4