Search Publications

CLEAR. II. Evidence for Early Formation of the Most Compact Quiescent Galaxies at High Redshift
DOI: 10.3847/1538-4357/aba004 Bibcode: 2020ApJ...898..171E

Papovich, Casey; Finkelstein, Steven L.; Cleri, Nikko J. +11 more

The origin of the correlations between mass, morphology, quenched fraction, and formation history in galaxies is difficult to define, primarily due to the uncertainties in galaxy star formation histories (SFHs). SFHs are better constrained for higher redshift galaxies, observed closer to their formation and quenching epochs. Here we use "nonparame…

2020 The Astrophysical Journal
eHST 53
Microwave Spectral Imaging of an Erupting Magnetic Flux Rope: Implications for the Standard Solar Flare Model in Three Dimensions
DOI: 10.3847/2041-8213/ab901a Bibcode: 2020ApJ...895L..50C

Reeves, Katharine K.; Chen, Bin; Yu, Sijie +1 more

We report microwave spectral imaging observations of an erupting magnetic flux rope during the early impulsive phase of the X8.2-class limb flare on 2017 September 10, obtained by the Expanded Owens Valley Solar Array. A few days prior to the eruption, when viewed against the disk, the flux rope appeared as a reverse S-shaped dark filament along t…

2020 The Astrophysical Journal
Hinode 53
Multiwavelength Variability of BL Lacertae Measured with High Time Resolution
DOI: 10.3847/1538-4357/aba693 Bibcode: 2020ApJ...900..137W

Chen, W. P.; Villata, M.; Carnerero, M. I. +54 more

In an effort to locate the sites of emission at different frequencies and physical processes causing variability in blazar jets, we have obtained high time-resolution observations of BL Lacertae over a wide wavelength range: with the Transiting Exoplanet Survey Satellite (TESS) at 6000-10000 Å with 2 minute cadence; with the Neil Gehrels Swift sat…

2020 The Astrophysical Journal
Gaia 53
Wide binaries are rare in open clusters
DOI: 10.1093/mnras/staa1877 Bibcode: 2020MNRAS.496.5176D

Kraus, A. L.; Deacon, N. R.

The population statistics of binary stars are an important output of star formation models. However, populations of wide binaries evolve over time due to interactions within a system's birth environment and the unfolding of wide, hierarchical triple systems. Hence, the wide binary populations observed in star-forming regions or OB associations may…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 53
An Evolutionary Study of Volatile Chemistry in Protoplanetary Disks
DOI: 10.3847/1538-4357/ab9e71 Bibcode: 2020ApJ...898...97B

Wilner, David J.; Cleeves, L. Ilsedore; Andrews, Sean M. +11 more

The volatile composition of a planet is determined by the inventory of gas and ice in the parent disk. The volatile chemistry in the disk is expected to evolve over time, though this evolution is poorly constrained observationally. We present Atacama Large Millimeter/submillimeter Array observations of C18O, C2H, and the isot…

2020 The Astrophysical Journal
Gaia 53
Shadowing and multiple rings in the protoplanetary disk of HD 139614
DOI: 10.1051/0004-6361/201936509 Bibcode: 2020A&A...635A.121M

Ménard, F.; Matter, A.; Henning, T. +20 more

Context. Shadows in scattered light images of protoplanetary disks are a common feature and support the presence of warps or misalignments between disk regions. These warps are possibly caused by an inclined (sub-)stellar companion embedded in the disk.
Aims: We aim to study the morphology of the protoplanetary disk around the Herbig Ae star …

2020 Astronomy and Astrophysics
Gaia 53
A Very Young Radio-loud Magnetar
DOI: 10.3847/2041-8213/ab9742 Bibcode: 2020ApJ...896L..30E

Campana, S.; Tiengo, A.; Götz, D. +20 more

The magnetar Swift J1818.0-1607 was discovered in 2020 March when Swift detected a 9 ms hard X-ray burst and a long-lived outburst. Prompt X-ray observations revealed a spin period of 1.36 s, soon confirmed by the discovery of radio pulsations. We report here on the analysis of the Swift burst and follow-up X-ray and radio observations. The burst …

2020 The Astrophysical Journal
XMM-Newton 53
The magnetic field and accretion regime of CI Tau
DOI: 10.1093/mnras/stz3368 Bibcode: 2020MNRAS.491.5660D

Moutou, C.; Ménard, F.; Donati, J. -F. +7 more

This paper exploits spectropolarimetric data of the classical T Tauri star CI Tau collected with ESPaDOnS at the Canada-France-Hawaii Telescope, with the aims of detecting and characterizing the large-scale magnetic field that the star hosts, and of investigating how the star interacts with the inner regions of its accretion disc through this fiel…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 53
Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era
DOI: 10.1051/0004-6361/201936360 Bibcode: 2020A&A...633A..34C

Jasniewicz, G.; Lagarde, N.; Smiljanic, R. +7 more

Context. Li is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors.
Aims: We present the results of a new large Li survey in red giant stars and combine it with surveys from the literature to probe the impact of rotation-induced mixing and thermohaline double-diffusive instability along stella…

2020 Astronomy and Astrophysics
Gaia Hipparcos 53
High-resolution Spectroscopy of the GD-1 Stellar Stream Localizes the Perturber near the Orbital Plane of Sagittarius
DOI: 10.3847/2041-8213/ab800c Bibcode: 2020ApJ...892L..37B

Conroy, Charlie; Cargile, Phillip A.; Johnson, Benjamin D. +6 more

The 100° long thin stellar stream in the Milky Way halo, GD-1, has an ensemble of features that may be due to dynamical interactions. Using high-resolution MMT/Hectochelle spectroscopy we show that a spur of GD-1-like stars outside of the main stream are kinematically and chemically consistent with the main stream. In the spur, as in the main stre…

2020 The Astrophysical Journal
Gaia 53