Search Publications
Drag-Based Model (DBM) Tools for Forecast of Coronal Mass Ejection Arrival Time and Speed
Dumbović, Mateja; Temmer, Manuela; Veronig, Astrid +4 more
Forecasting the arrival time of coronal mass ejections (CMEs) and their associated shocks is one of the key aspects of space weather research. One of the commonly used models is the analytical drag-based model (DBM) for heliospheric propagation of CMEs due to its simplicity and calculation speed. The DBM relies on the observational fact that slow …
Threads, Ribbons, and Rings in the Radio Galaxy IC 4296
Camilo, F.; White, S. V.; Condon, J. J. +5 more
The nearby elliptical galaxy IC 4296 has produced a large (510 kpc) low-luminosity radio source with typical FR I core/jet/lobe morphology. The unprecedented combination of brightness sensitivity, dynamic range, and angular resolution of a new 1.28 GHz MeerKAT continuum image reveals striking new morphological features, which we call threads, ribb…
Magnetic white dwarfs in post-common-envelope binaries
Gänsicke, B. T.; Breedt, E.; Marsh, T. R. +5 more
Magnitude-limited samples have shown that 20-25 per cent of cataclysmic variables contain white dwarfs with magnetic fields of Mega Gauss strength, in stark contrast to the approximately 5 per cent of single white dwarfs with similar magnetic field strengths. Moreover, the lack of identifiable progenitor systems for magnetic cataclysmic variables …
Determination of the escape velocity of the Milky Way using a halo sample selected based on proper motion
Helmi, Amina; Koppelman, Helmer H.
Context. The Gaia mission has provided the largest catalogue ever of sources with tangential velocity information. However, it is difficult to use this catalogue for dynamical studies because most of the stars lack line-of-sight velocity measurements. Recently, we presented a selection of ∼107 halo stars with accurate distances that wer…
Untangling the Galaxy. III. Photometric Search for Pre-main-sequence Stars with Deep Learning
Kounkel, Marina; Covey, Kevin; Hutchinson, Brian +2 more
A reliable census of pre-main-sequence stars with known ages is critical to our understanding of early stellar evolution, but historically there has been difficulty in separating such stars from the field. We present a trained neural network model, Sagitta, that relies on Gaia DR2 and 2 Micron All-Sky Survey photometry to identify pre-main-sequenc…
Radial Migration from the Metallicity Gradient of Open Clusters and Outliers
Zhao, Gang; Chen, Yuqin; Zhang, Haopeng
Radial migration is an important process in the evolution of the Galactic disk. The metallicity gradient of open clusters and its outliers provide an effective way to examine this process. In this work, we compile metallicity, age, and kinematic parameters for 225 open clusters and carry out a quantitative analysis of radial migration via the calc…
Jets from MRC 0600-399 bent by magnetic fields in the cluster Abell 3376
Nakanishi, Hiroyuki; Akamatsu, Hiroki; Takeuchi, Tsutomu T. +7 more
Galaxy clusters are known to harbour magnetic fields, the nature of which remains unresolved. Intra-cluster magnetic fields can be observed at the density contact discontinuity formed by cool and dense plasma running into hot ambient plasma1,2, and the discontinuity exists3 near the second-brightest galaxy4, MRC 06…
The ASKAP-EMU Early Science Project: 888 MHz radio continuum survey of the Large Magellanic Cloud
Maitra, Chandreyee; Koribalski, Bärbel S.; Norris, Ray P. +28 more
We present an analysis of a new 120 deg2 radio continuum image of the Large Magellanic Cloud (LMC) at 888 MHz with a bandwidth of 288 MHz and beam size of 13${_{.}^{\prime\prime}}$9 × 12${_{.}^{\prime\prime}}$1 from the Australian Square Kilometre Array Pathfinder processed as part of the Evolutionary Map of the Universe survey. The med…
A Planck-selected dusty proto-cluster at z = 2.16 associated with a strong overdensity of massive Hα-emitting galaxies
Koyama, Yusei; Kodama, Tadayuki; Tanaka, Ichi +6 more
We have discovered an overdensity of Hα-emitting galaxies associated with a Planck compact source in the COSMOS field (PHz G237.0+42.5) through narrow-band imaging observations with the Subaru Multi-Object InfraRed Camera and Spectrograph (MOIRCS). This Planck-selected dusty proto-cluster at z = 2.16 has 38 Hα emitters including six spectroscopica…
An Exploration of Model Degeneracies with a Unified Phase Curve Retrieval Analysis: The Light and Dark Sides of WASP-43 b
Waldmann, I. P.; Tinetti, G.; Edwards, B. +2 more
The analysis of exoplanetary atmospheres often relies upon the observation of transit or eclipse events. While very powerful, these snapshots provide mainly one-dimensional information on the planet structure and do not easily allow precise latitude-longitude characterizations. The phase curve technique, which consists of measuring the planet emis…