Search Publications

Relation of X-ray activity and rotation in M dwarfs and predicted time-evolution of the X-ray luminosity
DOI: 10.1051/0004-6361/201937408 Bibcode: 2020A&A...638A..20M

Scholz, A.; Stelzer, B.; Covey, K. R. +3 more

The relation of activity to rotation in M dwarfs is of high astrophysical interest because it provides observational evidence of the stellar dynamo, which is poorly understood for low-mass stars, especially in the fully convective regime. Previous studies have shown that the relation of X-ray activity to rotation consists of two different regimes:…

2020 Astronomy and Astrophysics
XMM-Newton 73
ARES. II. Characterizing the Hot Jupiters WASP-127 b, WASP-79 b, and WASP-62b with the Hubble Space Telescope
DOI: 10.3847/1538-3881/ab94a3 Bibcode: 2020AJ....160..109S

Drossart, Pierre; Blain, Doriann; Beaulieu, Jean-Philippe +24 more

This paper presents the atmospheric characterization of three large, gaseous planets: WASP-127 b, WASP-79 b, and WASP-62 b. We analyzed spectroscopic data obtained with the G141 grism (1.088-1.68 µm) of the Wide Field Camera 3 on board the Hubble Space Telescope using the Iraclis pipeline and the TauREx3 retrieval code, both of which are pub…

2020 The Astronomical Journal
eHST 73
A super-Earth and a sub-Neptune orbiting the bright, quiet M3 dwarf TOI-1266
DOI: 10.1051/0004-6361/202038616 Bibcode: 2020A&A...642A..49D

Watson, A. M.; Bouchy, F.; Queloz, D. +70 more

We report the discovery and characterisation of a super-Earth and a sub-Neptune transiting the bright (K = 8.8), quiet, and nearby (37 pc) M3V dwarf TOI-1266. We validate the planetary nature of TOI-1266 b and c using four sectors of TESS photometry and data from the newly-commissioned 1-m SAINT-EX telescope located in San Pedro Mártir (México). W…

2020 Astronomy and Astrophysics
Gaia 73
Not all stars form in clusters - Gaia-DR2 uncovers the origin of OB associations
DOI: 10.1093/mnras/staa1056 Bibcode: 2020MNRAS.495..663W

Kruijssen, J. M. Diederik; Rix, Hans-Walter; Ward, Jacob L.

Historically, it has often been asserted that most stars form in compact clusters. In this scenario, present-day gravitationally unbound OB associations are the result of the expansion of initially gravitationally bound star clusters. However, this paradigm is inconsistent with recent results, both theoretical and observational, that instead favou…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 72
Dual MeV gamma-ray and dark matter observatory - GRAMS Project
DOI: 10.1016/j.astropartphys.2019.07.002 Bibcode: 2020APh...114..107A

Odaka, Hirokazu; Aramaki, Tsuguo; Karagiorgi, Georgia +1 more

GRAMS (Gamma-Ray and AntiMatter Survey) is a novel project that can simultaneously target both astrophysical observations with MeV gamma rays and an indirect dark matter search with antimatter. The GRAMS instrument is designed with a cost-effective, large-scale LArTPC (Liquid Argon Time Projection Chamber) detector surrounded by plastic scintillat…

2020 Astroparticle Physics
INTEGRAL 72
Ubiquitous velocity fluctuations throughout the molecular interstellar medium
DOI: 10.1038/s41550-020-1126-z Bibcode: 2020NatAs...4.1064H

Henning, Thomas; Henshaw, Jonathan D.; Kruijssen, J. M. Diederik +23 more

The density structure of the interstellar medium determines where stars form and release energy, momentum and heavy elements, driving galaxy evolution1-4. Density variations are seeded and amplified by gas motion, but the exact nature of this motion is unknown across spatial scales and galactic environments5. Although dense s…

2020 Nature Astronomy
Herschel 72
Reflex motion in the Milky Way stellar halo resulting from the Large Magellanic Cloud infall
DOI: 10.1093/mnrasl/slaa029 Bibcode: 2020MNRAS.494L..11P

Peñarrubia, Jorge; Petersen, Michael S.

We present the results of N-body models of the Milky Way and Large Magellanic Cloud system and study the kinematic reflex motion in the stellar halo owing to the barycentre displacement of the disc. In agreement with previous studies, we find that the Milky Way disc may be moving at 40 km~s^{-1} relative to the barycentre prior to the Large Magell…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 72
The Gaia-ESO survey: the non-universality of the age-chemical-clocks-metallicity relations in the Galactic disc
DOI: 10.1051/0004-6361/202038055 Bibcode: 2020A&A...639A.127C

Baratella, M.; Gilmore, G.; Bayo, A. +36 more

Context. In the era of large spectroscopic surveys, massive databases of high-quality spectra coupled with the products of the Gaia satellite provide tools to outline a new picture of our Galaxy. In this framework, an important piece of information is provided by our ability to infer stellar ages, and consequently to sketch a Galactic timeline.

2020 Astronomy and Astrophysics
Gaia 72
Globular clusters in Coma cluster ultra-diffuse galaxies (UDGs): evidence for two types of UDG?
DOI: 10.1093/mnras/staa180 Bibcode: 2020MNRAS.492.4874F

Forbes, Duncan A.; Romanowsky, Aaron J.; Brodie, Jean P. +2 more

Ultra-diffuse galaxies (UDGs) reveal extreme properties. Here, we compile the largest study to date of 85 globular cluster (GC) systems around UDGs in the Coma cluster, using new deep ground-based imaging of the known UDGs and existing imaging from the Hubble Space Telescope of their GC systems. We find that the richness of GC systems in UDGs gene…

2020 Monthly Notices of the Royal Astronomical Society
eHST 72
Project AMIGA: The Circumgalactic Medium of Andromeda
DOI: 10.3847/1538-4357/aba49c Bibcode: 2020ApJ...900....9L

Brown, Thomas M.; Faucher-Giguère, Claude-André; Hafen, Zachary +22 more

Project AMIGA (Absorption Maps In the Gas of Andromeda) is a survey of the circumgalactic medium (CGM) of Andromeda (M31, ${R}_{\mathrm{vir}}$ ≃ 300 kpc) along 43 QSO sightlines at impact parameters 25 ≤ R ≤ 569 kpc (25 at R ≲ ${R}_{\mathrm{vir}}$). We use ultraviolet absorption measurements of Si II, Si III, Si IV, C II, and C IV from the Hubble …

2020 The Astrophysical Journal
eHST 72