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High-energy Jet Emission from GRS 1758–258 and 1E 1740.7–2942 with INTEGRAL?
Ubertini, Pietro; Bazzano, Angela; Rodi, James
GRS 1758–258 and 1E 1740.7–2942 are two long-known persistent black hole binaries in the Galactic center region. Using the International Gamma-Ray Astrophysics Laboratory (INTEGRAL)'s extensive monitoring of the Galactic center and bulge, we studied their temporal and spectral evolutions in the 30–610 keV energy range from 2003 March through 2022 …
KOBE-1: The first planetary system from the KOBE survey: Two planets likely residing in the sub-Neptune mass regime around a late K-dwarf
Nagel, E.; Aceituno, J.; Morales, J. C. +35 more
Context. K-dwarf stars are promising targets in the exploration of potentially habitable planets. Their properties, falling between G and M dwarfs, provide an optimal trade-off between the prospect of habitability and ease of detection. The KOBE experiment is a blind-search survey exploiting this niche, monitoring the radial velocity of 50 late-ty…
Cataclysmic variables from Sloan Digital Sky Survey - V (2020-2023) identified using machine learning
Thorstensen, John R.; Anderson, Scott F.; Brownstein, Joel R. +16 more
SDSS-V is carrying out a dedicated survey for white dwarfs, single and in binaries, and we report the analysis of the spectroscopy of 504 cataclysmic variables (CVs) and CV candidates obtained during the first 34 months of observations of SDSS-V. We developed a convolutional neural network (CNN) to aid with the identification of CV candidates amon…
Variations of Absolute Source Positions Determined from Quad-band VLBI Observations
Xu, Ming Hui; Charlot, Patrick
Active galactic nuclei (AGNs) observed with the very long baseline interferometry (VLBI) technique are used as fiducial references on the sky to precisely measure the shape and orientation of the Earth. Their positions form a celestial reference frame that plays an important role in both astronomy and geodesy. This study investigates the accuracy …
Instantaneous asymmetry of the Martian bow shock: A single- and dual-spacecraft study using MAVEN and Mars Express
Goetz, Charlotte; Gunell, Herbert; Nesbit-Östman, Sara
Aims. We study the instantaneous asymmetry of the Martian bow shock during a change in the direction of the interplanetary magnetic field (IMF) and for steady-state conditions. Specifically, we study the asymmetry with regard to the convective electric field and to the crustal fields of Mars. Methods. Two methods were used: First, a single-spacecr…
PSR J1947‑1120: A New Huntsman Millisecond Pulsar Binary
Strader, Jay; Dage, Kristen C.; Deneva, Julia S. +11 more
We present the discovery of PSR J1947–1120, a new huntsman millisecond pulsar with a red giant companion star in a 10.3 day orbit. This pulsar was found via optical, X-ray, and radio follow-up of the previously unassociated γ-ray source 4FGL J1947.6–1121. PSR J1947–1120 is the second confirmed pulsar in the huntsman class and establishes this as a…
Vertical kinematics of the young Galactic clusters
Elmegreen, Bruce; Alfaro, Emilio J.; Sánchez-Gil, M. Carmen
The young disc vertical phase is paramount in our understanding of Galaxy evolution. Analysing the vertical kinematics at different Galactic regions provides important information about the space-time variations of the Galactic potential. The vertical phase snail shell structure identified in Gaia Data Release 2 includes a wide age range. However,…
A first glimpse at the MeerKAT DEEP2 field at S-band
Camilo, F.; Kramer, M.; Menten, K. +15 more
We present the first wide-field extragalactic continuum catalogue with the MeerKAT S-band (2.5 GHz), of the radio-selected DEEP2 field. The combined image over the S1 (1.96-2.84 GHz) and S4 (2.62-3.50 GHz) sub-bands has an angular resolution of 6.8 arcsec
New Orbital Parameters of 850 Wide Visual Binary Stars and Their Statistical Properties
Izmailov, Igor; Khovritchev, Maxim
Based on positional observations and measurements of radial velocities, the orbits of 850 wide visual binary stars have been determined. The parameters of the log-normal distributions for the histograms of orbital periods, stellar masses, and semimajor axes in astronomical units have been obtained. The eccentricity histogram for binary stars with …
Hemispheric asymmetry of coronal bright point's number and area over solar cycles 23-24
Karachik, Nina V.; Minenko, Ekaterina P.
Temporal variations in the number and area of coronal bright points (CBPs) were studied separately in the Northern and Southern hemispheres over more than two solar cycles (years 1996-2022). Hemispheric asymmetry was identified in both the total number and area of CBPs, with differences reaching up to 15 per cent. Statistical analysis using Studen…