Search Publications
Buried AGNs in Advanced Mergers: Mid-infrared Color Selection as a Dual AGN Candidate Finder
Ellison, Sara L.; Ricci, Claudio; Blecha, Laura +7 more
A direct consequence of hierarchical galaxy formation is the existence of dual supermassive black holes, which may be preferentially triggered as active galactic nuclei (AGNs) during galaxy mergers. Despite decades of searching, however, dual AGNs are extremely rare, and most have been discovered serendipitously. Using the all-sky WISE survey, we …
Modeling observations of solar coronal mass ejections with heliospheric imagers verified with the Heliophysics System Observatory
Rodriguez, L.; Zhang, T. L.; Möstl, C. +19 more
We present an advance toward accurately predicting the arrivals of coronal mass ejections (CMEs) at the terrestrial planets, including Earth. For the first time, we are able to assess a CME prediction model using data over two thirds of a solar cycle of observations with the Heliophysics System Observatory. We validate modeling results of 1337 CME…
Tracing the Hercules stream with Gaia and LAMOST: new evidence for a fast bar in the Milky Way
Famaey, Benoit; Kawata, Daisuke; Hunt, Jason A. S. +1 more
The length and pattern speed of the Milky Way bar are still controversial. Photometric and spectroscopic surveys of the inner Galaxy, as well as gas kinematics, favour a long and slowly rotating bar, with corotation around a Galactocentric radius of 6 kpc. On the other hand, the existence of the Hercules stream in local velocity space favours a sh…
Intermittent Reconnection and Plasmoids in UV Bursts in the Low Solar Atmosphere
De Pontieu, B.; Martínez-Sykora, J.; Hansteen, V. H. +9 more
Magnetic reconnection is thought to drive a wide variety of dynamic phenomena in the solar atmosphere. Yet, the detailed physical mechanisms driving reconnection are difficult to discern in the remote sensing observations that are used to study the solar atmosphere. In this Letter, we exploit the high-resolution instruments Interface Region Imagin…
A tidal disruption event in the nearby ultra-luminous infrared galaxy F01004-2237
Mullaney, J.; Rose, M.; Tadhunter, C. +2 more
Tidal disruption events (TDEs), in which stars are gravitationally disrupted as they pass close to the supermassive black holes in the centres of galaxies 1 , are potentially important probes of strong gravity and accretion physics. Most TDEs have been discovered in large-area monitoring surveys of many thousands of galaxies, and a rela…
Rotating Starburst Cores in Massive Galaxies at z = 2.5
Übler, Hannah; Tamura, Yoichi; Kohno, Kotaro +21 more
We present spatially resolved ALMA observations of the CO J=3-2 emission line in two massive galaxies at z = 2.5 on the star-forming main sequence. Both galaxies have compact dusty star-forming cores with effective radii of {R}{{e}}=1.3+/- 0.1 {kpc} and {R}{{e}}=1.2+/- 0.1 {kpc} in the 870 µm continuum emission. The spa…
Formation of bi-lobed shapes by sub-catastrophic collisions. A late origin of comet 67P's structure
Benz, W.; Jutzi, M.
Context. The origin of the particular shape of comet 67P/Churyumov-Gerasimenko (67P) is a topic of active research. How and when it acquired its peculiar characteristics has distinct implications on the origin of the solar system and its dynamics.
Aims: We investigate how shapes such as that of comet 67P can result from a new type of low-ener…
Do galaxies that leak ionizing photons have extreme outflows?
Chisholm, J.; Schaerer, D.; Thuan, T. X. +5 more
Context. To reionize the early universe, high-energy photons must escape the galaxies that produce them. How these photons escape is debated because too many ionizing photons are absorbed even at small H I column densities. It has been suggested that stellar feedback drives galactic outflows out of star-forming regions, creating low density channe…
The Complete Local Volume Groups Sample - I. Sample selection and X-ray properties of the high-richness subsample
Babul, Arif; Raychaudhury, Somak; Ponman, Trevor J. +7 more
We present the Complete Local-Volume Groups Sample (CLoGS), a statistically complete optically selected sample of 53 groups within 80 Mpc. Our goal is to combine X-ray, radio and optical data to investigate the relationship between member galaxies, their active nuclei and the hot intra-group medium (IGM). We describe sample selection, define a 26-…
Interstellar Pickup Ion Observations to 38 au
McComas, D. J.; Schwadron, N. A.; Szalay, J. R. +9 more
We provide the first direct observations of interstellar H+ and He+ pickup ions in the solar wind from 22 to 38 au. We use the Vasyliunas and Siscoe model functional form to quantify the pickup ion distributions, and while the fit parameters generally lie outside their physically expected ranges, this form allows fits that qu…