Results 41 to 50 of about 12,012 (266)
Surface Density of Disk Galaxies in MOND
Universe, 2023 In this paper, we extend a paper by Milgrom (2009, MNRAS 398, 1023) dealing with the existence of a quasi-universal surface density for object of all mass and structure, if they are in the Newtonian regime, i.e., that their mean acceleration is larger ...
Antonino Del Popolo, Morgan Le Delliou
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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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Direct Imaging of a Toroidal Magnetic Field in the Inner Jet of NRAO 150
Galaxies, 2016 Most formation models and numerical simulations cause a helical magnetic field to form, accelerate and collimate jets in active galactic nuclei (AGN). For this reason, observational direct evidence for the existence of these helical magnetic fields is of
Sol N. Molina +5 more
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New Strong Constraints on the Central Behaviour of Spherical Galactic Models
Astronomy, 2023 First of all, we show that any spherically symmetric galactic model with integrated mass profile M(r)→0 as r→0 is physically correct close to the centre only provided that the circular velocity vc(r)→0 and the gravitational field g(r)→0 as r→0.
Marco Roncadelli, Giorgio Galanti
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Lensing by galaxy haloes in clusters of galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 1997 17 pages, LaTeX file, MNRAS in ...
Natarajan, Priyamvada, Kneib, Jean-Paul
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Quantitative Analysis of Galaxy‐Galaxy Lensing [PDF]
The Astrophysical Journal, 1997 20 pages, Plain-Tex, no macros needed, including 8 figures, submitted to Astrophysical ...
Schneider, Peter, Rix, Hans-Walter
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Emission Knots and Polarization Swings of Swinging Jets
Galaxies, 2016 Knots (emission features in jets of active galactic nuclei) often show non-ballistic dynamics and variable emission/polarization properties. We model these features as emission pattern propagating in a jet that carries a helical magnetic field and is ...
Maxim Lyutikov, Evgeniya Kravchenko
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Galaxies, 2023 We develop a lepton–hadron model for the possible origin of hard very high energy (VHE) spectra from a distant blazar. The model includes synchrotron self-Compton (SSC) and hadronic components.
Wenjing Dong, Qian Dong, Yonggang Zheng
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The Millennium Galaxy Catalogue: Galaxy Bimodality [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractGalaxy bimodality is caused by the bulge-disc nature of galaxies as opposed to two distinct galaxy classes. This is evident in the colour-structure plane which clearly shows that elliptical galaxies (bulge-only) lie in the red compact peak and late-type spiral galaxies (disc-dominated) lie in the blue diffuse peak.
Driver, Simon P. +2 more
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Structural and Morphological Properties of Ultraluminous Infrared Galaxies at 1 < z < 3
Open Astronomy, 2015 Using the Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) near-infrared high-resolution imaging from the 3D-HST survey, we analyze the morphology and structure of 502 ultraluminous infrared galaxies (ULIRGs; LIR > 1012L⊙) at 1 < z < 3. Their rest-
Fang Guanwen +3 more
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