Search Publications
Attention-gating for improved radio galaxy classification
Scaife, Anna M. M.; Bowles, Micah; Tang, Hongming +2 more
In this work, we introduce attention as a state-of-the-art mechanism for classification of radio galaxies, using convolutional neural networks. We present an attention-based model that performs on par with previous classifiers while using more than 50 per cent fewer parameters than the next smallest classic CNN application in this field. We demons…
CAPOS: The bulge Cluster APOgee Survey. I. Overview and initial ASPCAP results
Minniti, D.; Zoccali, M.; Rojas-Arriagada, A. +39 more
Context. Bulge globular clusters (BGCs) are exceptional tracers of the formation and chemodynamical evolution of this oldest Galactic component. However, until now, observational difficulties have prevented us from taking full advantage of these powerful Galactic archeological tools.
Aims: CAPOS, the bulge Cluster APOgee Survey, addresses thi…
Further Evidence for Tidal Spin-up of Hot Jupiter Host Stars
Winn, Joshua N.; Anderson, Kassandra R.; Tejada Arevalo, Roberto A.
For most hot Jupiters around main-sequence Sun-like stars, tidal torques are expected to transfer angular momentum from the planet's orbit to the star's rotation. The timescale for this process is difficult to calculate, leading to uncertainties in the history of orbital evolution of hot Jupiters. We present evidence for tidal spin-up by taking ad…
Non-Keplerian spirals, a gas-pressure dust trap, and an eccentric gas cavity in the circumbinary disc around HD 142527
Pinte, C.; Casassus, S.; Boehler, Y. +7 more
We present ALMA observations of the 12CO, 13CO, C18O J = 2-1 transitions and the 1.3 mm continuum emission for the circumbinary disc around HD 142527, at an angular resolution of ≈ 0${_{.}^{\prime\prime}}$3. We observe multiple spiral structures in intensity, velocity, and velocity dispersion for the 12C…
Measurements of Solar Differential Rotation Using the Century Long Kodaikanal Sunspot Data
Chatterjee, Subhamoy; Banerjee, Dipankar; Jha, Bibhuti Kumar +2 more
The rotational profile of the Sun is considered to be one of the key inputs in a solar dynamo model. Hence, precise and long-term measurements of this quantity is important for our understanding of solar magnetism and its variability. In this study, we use the newly digitised, white-light sunspot data (1923 - 2011) from Kodaikanal Solar Observator…
Physical properties of brightest cluster galaxies up to redshift 1.80 based on HST data
Durret, F.; Márquez, I.; Chu, A.
Context. Brightest cluster galaxies (BCGs) grow by accreting numerous smaller galaxies, and can be used as tracers of cluster formation and evolution in the cosmic web. However, there is still controversy regarding the main epoch of formation of BCGs; some authors believe they already formed before redshift z = 2, while others find that they are s…
An HST Survey of Protostellar Outflow Cavities: Does Feedback Clear Envelopes?
Manoj, P.; Kounkel, Marina; Pokhrel, Riwaj +10 more
We study protostellar envelope and outflow evolution using Hubble Space Telescope NICMOS or WFC3 images of 304 protostars in the Orion molecular clouds. These near-IR images resolve structures in the envelopes delineated by the scattered light of the central protostars with 80 au resolution, and they complement the 1.2 µm to 870 µm spe…
Discovery of 178 Giant Radio Galaxies in 1059 deg2 of the Rapid ASKAP Continuum Survey at 888 MHz
Andernach, Heinz; Jiménez-Andrade, Eric F.; Willis, Anthony G.
We report the results of a visual inspection of images of the Rapid ASKAP Continuum Survey (RACS) in search of extended radio galaxies (ERG) that reach or exceed linear sizes on the order of one Megaparsec. We searched a contiguous area of 1059 deg2 from RAJ = 20h20m to 06h20m, and ‑50∘<DecJ<‑40∘, which is covered by deep multi-band optical …
The VISCACHA survey. III. Star clusters counterpart of the Magellanic Bridge and Counter-Bridge in 8D
Geisler, D.; Bica, E.; Barbuy, B. +15 more
Context. The interactions between the Small and Large Magellanic Clouds (SMC and LMC) created the Magellanic Bridge; a stream of gas and stars pulled out of the SMC towards the LMC about 150 Myr ago. The tidal counterpart of this structure, which should include a trailing arm, has been predicted by models but no compelling observational evidence h…
Energetic Electron Distribution of the Coronal Acceleration Region: First Results from Joint Microwave and Hard X-Ray Imaging Spectroscopy
Krucker, Säm; Reeves, Katharine K.; Chen, Bin +2 more
Nonthermal sources located above bright flare arcades, referred to as the "above-the-loop-top" sources, have been often suggested as the primary electron acceleration site in major solar flares. The X8.2 limb flare on 2017 September 10 features such an above-the-loop-top source, which was observed in both microwaves and hard X-rays (HXRs) by the E…