Search Publications
Three new Galactic star clusters discovered in the field of the open cluster NGC 5999 with Gaia DR2
Corradi, W. J. B.; Ferreira, Filipe A.; Santos, J. F. C. +2 more
We report the serendipitous discovery of three new open clusters, named UFMG 1, UFMG 2, and UFMG 3 in the field of the intermediate-age cluster NGC 5999, by using Gaia DR2 data. A colour-magnitude filter tailored for a proper selection of main-sequence stars and red clump giants turned evident the presence of NGC 5999 and these three new stellar g…
Molecular complexity on disc scales uncovered by ALMA. Chemical composition of the high-mass protostar AFGL 4176
van Dishoeck, Ewine F.; Hogerheijde, Michiel R.; Ligterink, Niels F. W. +4 more
Context. The chemical composition of high-mass protostars reflects the physical evolution associated with different stages of star formation. In addition, the spatial distribution and velocity structure of different molecular species provide valuable information on the physical structure of these embedded objects. Despite an increasing number of i…
The white dwarf mass-radius relation and its dependence on the hydrogen envelope
Kepler, S. O.; Romero, Alejandra D.; Joyce, S. R. G. +2 more
We present a study of the dependence of the mass-radius relation for DA white dwarf stars on the hydrogen envelope mass and the impact on the value of log g, and thus the determination of the stellar mass. We employ a set of full evolutionary carbon-oxygen core white dwarf sequences with white dwarf mass between 0.493 and 1.05 M⊙. Compu…
Infrared Contributions of X-Ray Selected Active Galactic Nuclei in Dusty Star-forming Galaxies
Azadi, Mojegan; Cooray, Asantha; Ma, Jingzhe +3 more
We investigate the infrared (IR) contribution from supermassive black hole activity versus host galaxy emission in the mid- to far-IR spectrum for a large sample of X-ray bright active galactic nuclei (AGN) residing in dusty, star-forming host galaxies. We select 703 AGN with {L}{{X}}={10}42{--}{10}46 erg s-1<…
SWAN/SOHO Lyman-α Mapping: The Hydrogen Geocorona Extends Well Beyond the Moon
Schmidt, W.; Bertaux, J. -L.; Quémerais, E. +2 more
The Earth's hydrogen exosphere Lyman-α radiation was mapped with the Solar Wind Anisotropies/Solar and Heliospheric Observatory (SWAN/SOHO) instrument in January 1996, 1997, and 1998 (low solar activity). The use of a hydrogen absorption cell allowed to disentangle the interplanetary emission from the geocoronal one and to assign the absorbed sign…
A stellar relic filament in the Orion star-forming region
Anderson, Richard I.; Boffin, Henri M. J.; Jerabkova, Tereza +1 more
We report the discovery of the oldest stellar substructure in the Orion star-forming region (OSFR), the Orion relic filament. The relic filament is physically associated with the OSFR, as demonstrated by Gaia DR2 photometry and astrometry, as well as by targeted radial velocity follow-up observations of a bright subsample of proper motion-selected…
First ALMA Millimeter-wavelength Maps of Jupiter, with a Multiwavelength Study of Convection
de Pater, Imke; Sault, R. J.; Wong, Michael H. +15 more
We obtained the first maps of Jupiter at 1-3 mm wavelength with the Atacama Large Millimeter/Submillimeter Array (ALMA) on 2017 January 3-5, just days after an energetic eruption at 16.°5S jovigraphic latitude had been reported by the amateur community, and about two to three months after the detection of similarly energetic eruptions in the north…
Detection of a 50° long Trailing Tidal Tail for the Globular Cluster M5
Grillmair, Carl J.
Using photometry and proper motions from Gaia Data Release 2, we detect a 50° long stream of about 70 stars extending westward from the halo globular cluster M5. Based on the similarities in distance, proper motions, inferred color-magnitude distribution, and trajectory, we identify this stream as the trailing tidal tail of M5. While the surface d…
HST unveils a compact mildly relativistic broad-line region in the candidate true type 2 NGC 3147
Laor, Ari; Bianchi, Stefano; La Franca, Fabio +9 more
NGC 3147 has been considered the best case of a true type 2 AGN: an unobscured AGN, based on the unabsorbed compact X-ray continuum, which lacks a broad-line region (BLR). However, the very low luminosity of NGC 3147 implies a compact BLR, which produces very broad lines, hard to detect against the dominant background host galaxy. Narrow (0.1 arcs…
Episodically Active Asteroid 6478 Gault
Kotulla, Ralf; Jewitt, David; Rajagopal, Jayadev +4 more
We present imaging and spectroscopic observations of 6478 Gault, a ∼6 km diameter inner main-belt asteroid currently exhibiting strong, comet-like characteristics. Three distinct tails indicate that ultra-slow dust (ejection speed 0.15 ± 0.05 m s-1) was emitted from Gault in separate episodes beginning UT 2018 October 28 ± 5 (Tail A), U…