Search Publications
A comprehensive investigation of the variable overcontact system EH Cancri
Nelson, Robert H.; Alton, Kevin B.; StÈ©pień, Kazimierz
Precise multi-color CCD-derived photometric data were obtained from EH Cnc at two sites during 2010, 2014 and 2018 wherein each epoch used a different instrument. This has provided a unique opportunity to investigate parameter uncertainty following Roche modeling of light curves optimized by differential corrections using the Wilson–Devinney code.…
Galaxy and Mass Assembly: A Comparison between Galaxy-Galaxy Lens Searches in KiDS/GAMA
Holwerda, Benne W.; Hopkins, Andrew M.; Bilicki, Maciej +9 more
Strong gravitational lenses are a rare and instructive type of astronomical object. Identification has long relied on serendipity, but different strategies—such as mixed spectroscopy of multiple galaxies along the line of sight, machine-learning algorithms, and citizen science—have been employed to identify these objects as new imaging surveys bec…
Observations and numerical modelling of a convective disturbance in a large-scale cyclone in Jupiter's South Temperate Belt
Hansen, C. J.; Hueso, R.; Sánchez-Lavega, A. +8 more
Moist convective storms in Jupiter develop frequently and can trigger atmospheric activity of different scales, from localized storms to planetary-scale disturbances including convective activity confined inside a larger meteorological system. In February 2018 a series of convective storms erupted in Jupiter's South Temperate Belt (STB) (planetoce…
Electric Current Evolution at the Footpoints of Solar Eruptions
Barczynski, Krzysztof; Aulanier, Guillaume; Janvier, Miho +2 more
Electric currents play a critical role in the triggering of solar flares and their evolution. The aim of the present paper is to test whether the surface electric current has a surface or subsurface fixed source as predicted by the circuit approach of flare physics, or is the response of the surface magnetic field to the evolution of the coronal m…
Constraints on the spin-pole orientation, jet morphology, and rotation of interstellar comet 2I/Borisov with deep HST imaging
Lisse, Carey M.; Bolin, Bryce T.
We present high resolution, deep imaging of interstellar comet 2I/Borisov taken with the Hubble Space Telescope/Wide Field Camera 3 (HST/WFC3) on 2019 December 8 UTC and 2020 January 27 UTC (HST GO 16040, PI: Bolin) before and after its perihelion passage in combination with HST/WFC3 images taken on 2019 October 12 UTC and 2019 November 16 UTC (HS…
Microlensing Analysis for the Gravitational Lens Systems SDSS0924+0219, Q1355-2257, and SDSS1029+2623
Mediavilla, E.; Rojas, K.; Fian, C. +3 more
We use spectroscopic observations of the gravitationally lensed systems SDSS0924+0219(BC), Q1355-2257(AB), and SDSS1029+2623(BC) to analyze microlensing and dust extinction in the observed components. We detect chromatic microlensing effects in the continuum and microlensing in the broad emission line profiles of the systems SDSS0924+0219(BC) and …
Bayesian Characterization of Main-sequence Binaries in the Old Open Cluster NGC 188
Cohen, Roger E.; von Hippel, Ted; Geller, Aaron M.
The binary fractions of open and globular clusters yield powerful constraints on their dynamical state and evolutionary history. We apply publicly available Bayesian analysis tools to a UBV RIJHK S photometric catalog of the open cluster NGC 188 to detect and characterize photometric binaries along the cluster main sequence. This tech…
AGILE and Konus-Wind Observations of GRB 190114C: The Remarkable Prompt and Early Afterglow Phases
Antonelli, L. A.; Costa, E.; Barbiellini, G. +36 more
GRB 190114C represents a breakthrough for the physics of gamma-ray bursts (GRBs), being the first GRB with delayed emission above 300 GeV, as reported by MAGIC. We present in this paper the sub-MeV/MeV data of the prompt and early afterglow emissions of GRB 190114C, as detected by AGILE and Konus-Wind, in the 20 keV-100 MeV energy range. The first…
The auroral radio emission of the magnetic B-type star ρ-=OphC
Umana, G.; Fossati, L.; Loru, S. +19 more
The non-thermal radio emission of main-sequence early-type stars is a signature of stellar magnetism. We present multiwavelength (1.6-16.7 GHz) ATCA measurements of the early-type magnetic star ρ-=OphC, which is a flat-spectrum non-thermal radio source. The ρ-=OphC radio emission is partially circularly polarized with a steep spectral dependence: …
Connecting measurements of solar and stellar brightness variations
Solanki, S. K.; Shapiro, A. I.; Krivova, N. A. +3 more
Context. A comparison of solar and stellar brightness variations is hampered by the difference in spectral passbands that are used in observations, and also by the possible difference in the inclination of the solar and stellar rotation axes from the line of sight.
Aims: We calculate the rotational variability of the Sun as it would be measur…