The Distribution of Open Clusters in the Galaxy
Frontiers in Astronomy and Space Sciences, 2021 In this work we explore the new catalog of galactic open clusters that became available recently, containing 1,750 clusters that have been re-analyzed using the Gaia DR2 catalog to determine the stellar memberships.
Hektor Monteiro +3 more
doaj +1 more source
The Principle of Maximum Entropy and the Distribution of Mass in Galaxies
Universe, 2022 We do not have a final answer to the question of why galaxies choose a particular internal mass distribution. Here we examine whether the distribution is set by thermodynamic equilibrium (TE).
Jorge Sánchez Almeida
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The Quest for the Nature of the Dark Matter: The Need of a New Paradigm
Astronomy, 2023 The phenomenon of the Dark matter baffles the researchers: the underlying dark particle has escaped so far the detection and its astrophysical role appears complex and entangled with that of the standard luminous particles.
Fabrizio Nesti +2 more
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Quantitative Morphology of High-Redshift Galaxies Using GALEX Ultraviolet Images of Nearby Galaxies [PDF]
Journal of Astronomy and Space Sciences, 2017 We present simulations of the optical-band images of high-redshift galaxies utilizing 845 near-ultraviolet (NUV) images of nearby galaxies obtained through the Galaxy Evolution Explorer (GALEX). We compute the concentration (C), asymmetry (A), Gini (G),
Bum-Suk Yeom +6 more
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Warm Dark Matter Galaxies with Central Supermassive Black Holes
Universe, 2022 We generalize the Thomas–Fermi approach to galaxy structure to include central supermassive black holes and find, self-consistently and non-linearly, the gravitational potential of the galaxy plus the central black hole (BH) system.
Hector J. de Vega, Norma G. Sanchez
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Galaxy Phase-Space Density Data Preclude That Bose–Einstein Condensate Be the Total Dark Matter
Universe, 2022 Ultralight scalars with a typical mass of the order m∼10−22 eV and light scalars forming a Bose–Einstein condensate (BEC) exhibit a Jeans length in the kpc scale and were therefore proposed as dark matter (DM) candidates.
Héctor J. de Vega, Norma G. Sanchez
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Spirality: A Novel Way to Measure Spiral Arm Pitch Angle
Galaxies, 2022 We present the MATLAB code Spirality, a novel method for measuring spiral arm pitch angles by fitting galaxy images to spiral templates of known pitch. Computation time is typically on the order of 2 min per galaxy, assuming 8 GB of working memory.
Deanna Shields +9 more
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RR Lyrae Variables as Tracers of the Galactic Bulge Kinematic Structure
Universe, 2022 RR Lyrae stars are recognized as some of the oldest stars in the Universe. In addition, they are some of the few old celestial objects for which distances can be reliably inferred.
Andrea M. Kunder
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Vertical Density Distribution of the Galaxy from Star Count Analysis [PDF]
Journal of Astronomy and Space Sciences, 2002 The five space density distribution D(z) with distance perpendicular to the Galactic plane were combined. The scale heights and the local densities at z = 0 of the thin disk, thick disk, and the halo components were estimated from the nonlinear least ...
Young-Jong Sohn
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Targeted decrease of portal hepatic pressure gradient improves ascites control after TIPS
Hepatology, EarlyView., 2022 The river diagram demonstrates that after transjugular intrahepatic portosystemic shunt insertion (TIPS) the majority of patients without ascites and 50% of the patients with ascites detectable at ultrasound, show the best response in the long term follow‐up.
Alexander Queck +14 more
wiley +1 more source