Search Publications

Resolving the FU Orionis System with ALMA: Interacting Twin Disks?
DOI: 10.3847/1538-4357/ab5c1b Bibcode: 2020ApJ...889...59P

Liu, Hauyu Baobab; Williams, Jonathan; Zhu, Zhaohuan +7 more

FU Orionis objects are low-mass pre-main sequence stars characterized by dramatic outbursts several magnitudes in brightness. These outbursts are linked to episodic accretion events in which stars gain a significant portion of their mass. The physical processes behind these accretion events are not yet well understood. The archetypal FU Ori system…

2020 The Astrophysical Journal
Gaia 43
Multiwavelength Follow-up of the Hyperluminous Intermediate-mass Black Hole Candidate 3XMM J215022.4-055108
DOI: 10.3847/2041-8213/ab745b Bibcode: 2020ApJ...892L..25L

Romanowsky, Aaron J.; Remillard, Ronald A.; Strader, Jay +6 more

We recently discovered the X-ray/optical outbursting source 3XMM J215022.4-055108. It was best explained as the tidal disruption of a star by an intermediate-mass black hole of mass of a few tens of thousand solar masses in a massive star cluster at the outskirts of a large barred lenticular galaxy at DL = 247 Mpc. However, we could not…

2020 The Astrophysical Journal
XMM-Newton 43
Lupus DANCe. Census of stars and 6D structure with Gaia-DR2 data
DOI: 10.1051/0004-6361/202038717 Bibcode: 2020A&A...643A.148G

Bertin, E.; Miret-Roig, N.; Bouy, H. +8 more

Context. Lupus is recognised as one of the closest star-forming regions, but the lack of trigonometric parallaxes in the pre-Gaia era hampered many studies on the kinematic properties of this region and led to incomplete censuses of its stellar population.
Aims: We use the second data release of the Gaia space mission combined with published …

2020 Astronomy and Astrophysics
Gaia 43
Exploring the Stellar Age Distribution of the Milky Way Bulge Using APOGEE
DOI: 10.3847/1538-4357/abaeee Bibcode: 2020ApJ...901..109H

Cohen, Roger E.; Cunha, Katia; Smith, Verne V. +20 more

We present stellar age distributions of the Milky Way bulge region using ages for ∼6000 high-luminosity ( $\mathrm{log}(g)\lt 2.0$ ), metal-rich ([Fe/H] ≥ -0.5) bulge stars observed by the Apache Point Observatory Galactic Evolution Experiment. Ages are derived using The Cannon label-transfer method, trained on a sample of nearby luminous giants w…

2020 The Astrophysical Journal
Gaia 43
Expanding the Y Dwarf Census with Spitzer Follow-up of the Coldest CatWISE Solar Neighborhood Discoveries
DOI: 10.3847/1538-4357/ab6215 Bibcode: 2020ApJ...889...74M

Meisner, Aaron M.; Cushing, Michael C.; Kirkpatrick, J. Davy +11 more

We present Spitzer 3.6 and 4.5 µm follow-up of 170 candidate extremely cool brown dwarfs newly discovered via the combination of Wide-field Infrared Survey Explorer (WISE) and NEOWISE imaging at 3-5 µm. CatWISE, a joint analysis of archival WISE and NEOWISE data, has improved upon the motion measurements of AllWISE by leveraging a >…

2020 The Astrophysical Journal
Gaia 43
JINGLE - IV. Dust, H I gas, and metal scaling laws in the local Universe
DOI: 10.1093/mnras/staa1496 Bibcode: 2020MNRAS.496.3668D

Clements, D. L.; Lin, L.; Saintonge, A. +29 more

Scaling laws of dust, H I gas, and metal mass with stellar mass, specific star formation rate, and metallicity are crucial to our understanding of the build-up of galaxies through their enrichment with metals and dust. In this work, we analyse how the dust and metal content varies with specific gas mass (MH I/M) across a div…

2020 Monthly Notices of the Royal Astronomical Society
Herschel 43
Magnetic Flux of Active Regions Determining the Eruptive Character of Large Solar Flares
DOI: 10.3847/1538-4357/aba6ef Bibcode: 2020ApJ...900..128L

Veronig, Astrid M.; Hou, Yijun; Li, Ting +3 more

We establish the largest eruptive/confined flare database to date and analyze 322 flares of Geostationary Operational Environmental Satellite class M1.0 and larger that occurred during 2010-2019, i.e., almost spanning all of solar cycle 24. We find that the total unsigned magnetic flux ( ${{\rm{\Phi }}}_{\mathrm{AR}}$ ) of active regions (ARs) is …

2020 The Astrophysical Journal
SOHO 43
A Free-floating or Wide-orbit Planet in the Microlensing Event OGLE-2019-BLG-0551
DOI: 10.3847/1538-3881/ab8aeb Bibcode: 2020AJ....159..262M

Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +32 more

High-cadence observations of the Galactic bulge by the microlensing surveys led to the discovery of a handful of extremely short-timescale microlensing events that can be attributed to free-floating or wide-orbit planets. Here, we report the discovery of another strong free-floating planet candidate, which was found from the analysis of the gravit…

2020 The Astronomical Journal
Gaia eHST 43
A Helium-flash-induced Mixing Event Can Explain the Lithium Abundances of Red Clump Stars
DOI: 10.3847/2041-8213/abb45f Bibcode: 2020ApJ...901L..18S

Schwab, Josiah

Observations demonstrate that the surface abundance of ${}^{7}\mathrm{Li}$ in low-mass stars changes dramatically between the tip of the red giant branch and the red clump. This naturally suggests an association with the helium core flash, which occurs between these two stages. Using stellar evolution models and a simple, ad hoc mixing prescriptio…

2020 The Astrophysical Journal
Gaia 43
Stellar 3D kinematics in the Draco dwarf spheroidal galaxy
DOI: 10.1051/0004-6361/201935613 Bibcode: 2020A&A...633A..36M

Massari, D.; Helmi, A.; Spina, L. +3 more


Aims: We present the first three-dimensional internal motions for individual stars in the Draco dwarf spheroidal galaxy.
Methods: By combining first-epoch Hubble Space Telescope observations and second-epoch Gaia Data Release 2 positions, we measured the proper motions of 149 sources in the direction of Draco. We determined the line-of-s…

2020 Astronomy and Astrophysics
Gaia eHST 43