Search Publications

Closed depressions in Kotido crater, Arabia Terra, Mars. Possible evidence of evaporite dissolution-induced subsidence
DOI: 10.1016/j.icarus.2020.113680 Bibcode: 2020Icar..34113680P

García-Arnay, Ángel; Gutiérrez, Francisco; Baioni, Davide +3 more

The identification of karst sinkholes in Mars may provide evidence of dissolution processes caused by liquid water and information on paleoclimatic and paleohydrological conditions. This work presents a comprehensive cartographic inventory of 513 closed depressions developed on evaporite-bearing Equatorial Layered Deposits (ELDs) within Kotido cra…

2020 Icarus
MEx 6
Two Substructures in the nearby Stellar Halo Found in Gaia and RAVE
DOI: 10.3847/1538-4357/ab8733 Bibcode: 2020ApJ...895...23L

Shi, Jianrong; Ma, Jun; Du, Cuihua +4 more

We use the second Gaia data release (Gaia DR2), combined with Radial Velocity Experiment spectroscopic surveys, to identify the substructures in the nearby stellar halo. We select 3845 halo stars kinematically and chemically and determine their density distribution in energy and angular momentum space. To select the substructures from overdensitie…

2020 The Astrophysical Journal
Gaia 6
Early High-contrast Imaging Results with Keck/NIRC2-PWFS: The SR 21 Disk
DOI: 10.3847/1538-3881/abc69a Bibcode: 2020AJ....160..283U

Baranec, Christoph; Jensen-Clem, Rebecca; Uyama, Taichi +22 more

High-contrast imaging of exoplanets and protoplanetary disks depends on wave front sensing and correction made by adaptive optics instruments. Classically, wave front sensing has been conducted at optical wavelengths, which made high-contrast imaging of red targets such as M-type stars or extincted T Tauri stars challenging. Keck/NIRC2 has combine…

2020 The Astronomical Journal
Gaia 6
Axial Asymmetry Studies in Gaia Data Release 2 Yield the Pattern Speed of the Galactic Bar
DOI: 10.3847/2041-8213/aba905 Bibcode: 2020ApJ...899L..14H

Yanny, Brian; Gardner, Susan; Hinkel, Austin

Our recent studies of axial-symmetry breaking in the nearby (d < 3 kpc) star counts are sensitive to the distortions of stellar orbits perpendicular and parallel to the orientation of the bar just within and beyond the outer Lindblad resonance (OLR) radius. Using the location of the sign flip in the left-right asymmetry in stars counts about th…

2020 The Astrophysical Journal
Gaia 6
The XXL Survey. XLIII. The quasar radio loudness dichotomy exposed via radio luminosity functions obtained by combining results from COSMOS and XXL-S X-ray selected quasars
DOI: 10.1051/0004-6361/201936776 Bibcode: 2020A&A...642A.125C

Smolčić, V.; Pierre, M.; Leslie, S. +13 more

We studied a sample of 274 radio and X-ray selected quasars (XQSOs) detected in the COSMOS and XXL-S radio surveys at 3 GHz and 2.1 GHz, respectively. This sample was identified by adopting a conservative threshold in X-ray luminosity, LX [2-10 keV] ≥ 1044 erg s-1, selecting only the most powerful quasars. A number…

2020 Astronomy and Astrophysics
Herschel 6
Modelling of 35-d superorbital cycle of B and V light curves of IMXB HZ Her/Her X-1
DOI: 10.1093/mnras/staa2829 Bibcode: 2020MNRAS.499.1747K

Klochkov, D.; Bikmaev, I. F.; Wilms, J. +13 more

The X-ray binary Her X-1 consists of an accreting neutron star and the optical component HZ Her. The 35-d X-ray superorbital variability of this system is known, since its discovery in 1972 by the Uhuru satellite and is believed to be caused by forced precession of a warped accretion disc tilted to the orbital plane. We argue that the observed fea…

2020 Monthly Notices of the Royal Astronomical Society
INTEGRAL 6
CzeV1731: The unique doubly eclipsing quadruple system
DOI: 10.1051/0004-6361/202038656 Bibcode: 2020A&A...642A..63Z

Wolf, M.; Gazeas, K.; Mašek, M. +14 more

We report the discovery of the relatively bright (V = 10.5 mag), doubly eclipsing 2+2 quadruple system CzeV1731. This is the third known system of its kind, in which the masses are determined for all four stars and both the inner and outer orbits are characterized. The inner eclipsing binaries are well-detached systems moving on circular orbits: p…

2020 Astronomy and Astrophysics
Gaia 6
Wide-field study of the peculiar globular cluster system hosted by the field lenticular NGC 1172
DOI: 10.1093/mnras/staa2967 Bibcode: 2020MNRAS.499.2554E

Salinas, Ricardo; Gómez, Matías; Caso, Juan Pablo +2 more

We present a wide-field study of the globular cluster system (GCS) of the field lenticular galaxy NGC 1172, based on observations from Gemini Multi-Object Spectrograph/Gemini (optical), FourStar/Magellan (NIR), and archival data from ACS/Hubble Space Telescope (optical). This analysis covers the full extension of the GCS, and results in a value of…

2020 Monthly Notices of the Royal Astronomical Society
eHST 6
The phenomenon of shape evolution from solar-driven outgassing for analogues of small Kuiper belt objects
DOI: 10.1093/mnras/staa132 Bibcode: 2020MNRAS.492.5152Z

Rezac, L.; Li, J. -Y.; Zhao, Y. +1 more

One of the key findings of the Rosetta mission to the Jupiter-family comet 67P/Churyumov-Gerasimenko was its peculiar bi-lobed shape and its apparent Northern/Southern hemispheric dichotomy in large-scale morphology. This has re-ignited scientific discussions on the topic of the origin, evolution and age of the nucleus. In this work, we conduct a …

2020 Monthly Notices of the Royal Astronomical Society
Rosetta 6
The Kinematic Evolution of Erupting Structures in Confined Solar Flares
DOI: 10.3847/2041-8213/abc5b0 Bibcode: 2020ApJ...904L...2H

Cheng, X.; Ding, M. D.; Huang, Z. W.

In this Letter, we study the kinematic properties of ascending hot blobs associated with confined flares. Taking advantage of high-cadence extreme-ultraviolet images provided by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, we find that for the 26 events selected here, the hot blobs are first impulsively accelerated out…

2020 The Astrophysical Journal
SOHO 6