Search Publications

The Nature of Soft Excess in ESO 362-G18 Revealed by XMM-Newton and NuSTAR Spectroscopy
DOI: 10.3847/1538-4357/abf430 Bibcode: 2021ApJ...913...13X

Walton, Dominic J.; García, Javier A.; Harrison, Fiona A. +3 more

We present a detailed spectral analysis of the joint XMM-Newton and NuSTAR observations of the active galactic nuclei (AGNs) in the Seyfert 1.5 Galaxy ESO 362-G18. The broadband (0.3-79 keV) spectrum shows the presence of a power-law continuum with a soft excess below 2 keV, iron Kα emission (∼6.4 keV), and a Compton hump (peaking at ∼20 keV). We …

2021 The Astrophysical Journal
XMM-Newton 29
The White Dwarf Binary Pathways Survey - IV. Three close white dwarf binaries with G-type secondary stars
DOI: 10.1093/mnras/staa3815 Bibcode: 2021MNRAS.501.1677H

Gänsicke, B. T.; Rebassa-Mansergas, A.; Raddi, R. +12 more

Constraints from surveys of post-common envelope binaries (PCEBs) consisting of a white dwarf plus an M-dwarf companion have led to significant progress in our understanding of the formation of close white dwarf binary stars with low-mass companions. The white dwarf binary pathways project aims at extending these previous surveys to larger seconda…

2021 Monthly Notices of the Royal Astronomical Society
Gaia Hipparcos 29
The Fundamental Plane in the LEGA-C Survey: Unraveling the M/L Ratio Variations of Massive Star-forming and Quiescent Galaxies at z ∼ 0.8
DOI: 10.3847/1538-4357/abf1e7 Bibcode: 2021ApJ...913..103D

Bell, Eric F.; Maseda, Michael V.; D'Eugenio, Francesco +10 more

We explore the connection between the kinematics, structures and stellar populations of massive galaxies at 0.6 < z < 1.0 using the fundamental plane (FP). Combining stellar kinematic data from the Large Early Galaxy Astrophysics Census (LEGA-C) survey with structural parameters measured from deep Hubble Space Telescope imaging, we obtain a …

2021 The Astrophysical Journal
eHST 29
The (im)possibility of strong chemical tagging
DOI: 10.1051/0004-6361/202141779 Bibcode: 2021A&A...654A.151C

Castro-Ginard, A.; Casamiquela, L.; Anders, F. +1 more

Context. The possibility of identifying co-natal stars that have dispersed into the Galactic disc based on chemistry alone is called strong chemical tagging. It has been debated for a long time whether this is indeed feasible; it holds the promise of reconstructing the detailed star formation history of a large fraction of stars in the Galactic di…

2021 Astronomy and Astrophysics
Gaia 29
Uniform Forward-modeling Analysis of Ultracool Dwarfs. I. Methodology and Benchmarking
DOI: 10.3847/1538-4357/abf8b2 Bibcode: 2021ApJ...916...53Z

Line, Michael R.; Marley, Mark S.; Liu, Michael C. +2 more

We present a forward-modeling framework using the Bayesian inference tool Starfish and cloudless Sonora-Bobcat model atmospheres to analyze low-resolution (R ≈ 80-250) near-infrared (1.0-2.5 µm) spectra of T dwarfs. Our approach infers effective temperatures, surface gravities, metallicities, radii, and masses, and by accounting for uncertai…

2021 The Astrophysical Journal
Gaia 29
Radial structure and formation of the Milky Way disc
DOI: 10.1051/0004-6361/202140453 Bibcode: 2021A&A...655A.111K

Katz, D.; Haywood, M.; Gómez, A. +2 more

Context. The formation of the Galactic disc is an enthusiastically debated issue. Numerous studies and models seek to identify the dominant physical process(es) that shaped its observed properties; for example, satellite accretion, starburst, quenching, gas infall, and stellar radial migration.
Aims: Taking advantage of the improved coverage …

2021 Astronomy and Astrophysics
Gaia 29
Solar wind turbulence: Connections with energetic particles
DOI: 10.1016/j.newast.2020.101507 Bibcode: 2021NewA...8301507O

Oughton, Sean; Engelbrecht, N. Eugene

For the solar wind, a wealth of observational evidence indicates that turbulence is an important dynamical process for velocity (v), magnetic (b), and other related fluctuations at MHD (fluid) scales. Here we review such observations and turbulence features, including discussion of when wave or turbulence descriptions can (or cannot) explain the o…

2021 New Astronomy
Cluster Ulysses 29
Revealing the Structure and Internal Rotation of the Sagittarius Dwarf Spheroidal Galaxy with Gaia and Machine Learning
DOI: 10.3847/1538-4357/abd5bf Bibcode: 2021ApJ...908..244D

van der Marel, Roeland P.; Fardal, Mark A.; Sohn, Sangmo Tony +3 more

We present a detailed study of the internal structure and kinematics of the core of the Sagittarius dwarf spheroidal galaxy (Sgr). Using machine-learning techniques, we have combined the information provided by 3300 RR Lyrae stars, more than 2000 spectroscopically observed stars, and the Gaia second data release to derive the full phase space, i.e…

2021 The Astrophysical Journal
Gaia eHST 29
Dust-enshrouded AGNs Can Dominate Host-galaxy-scale Cold Dust Emission
DOI: 10.3847/1538-4357/ac185f Bibcode: 2021ApJ...921...55M

Smith, Howard A.; Rosenthal, Lee J.; McKinney, Jed +4 more

It is widely assumed that long-wavelength infrared (IR) emission from cold dust (T ~ 20-40 K) is a reliable tracer of star formation even in the presence of a bright active galactic nucleus (AGN). Based on radiative transfer (RT) models of clumpy AGN tori, hot dust emission from the torus contributes negligibly to the galaxy spectral energy distri…

2021 The Astrophysical Journal
Herschel 29
Stellar substructures in the periphery of the Magellanic Clouds with the VISTA hemisphere survey from the red clump and other tracers
DOI: 10.1093/mnras/stab1075 Bibcode: 2021MNRAS.505.2020E

Sun, Ning-Chen; de Grijs, Richard; Ripepi, Vincenzo +11 more

We study the morphology of the stellar periphery of the Magellanic Clouds in search of substructure using near-infrared imaging data from the Visible and Infrared Survey Telescope for Astronomy Hemisphere Survey. Based on the selection of different stellar populations using the (J - Ks, Ks) colour-magnitude diagram, we confir…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 29