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Celestial Mechanics and Dynamical Astronomy, 2011 We study the role of asymptotic curves in supporting the spiral structure of a N-body model simulating a barred spiral galaxy. Chaotic orbits with initial conditions on the unstable asymptotic curves of the main unstable periodic orbits follow the shape ...
Contopoulos, George, Harsoula, Mirella
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Six spiral galaxies lacking dark matter [PDF]
Scientific ReportsDark matter is believed to be the essential building blocks of galaxy formation. While instances of galaxies lacking dark matter have been observed, these occurrences are typically linked to specific formation mechanisms, making them stand out as unique ...
Cheng-Yu Chen, Chorng-Yuan Hwang
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A Cloud-Scale View of the Molecular Gas Disk in the Whirlpool Galaxy and Beyond [PDF]
EPJ Web of Conferences, 2022 The nearby galaxy M51 (also known as the Whirlpool galaxy) hosts an iconic grand-design spiral pattern and both IRAM facilities conducted the first cloud-scale (∼50 pc resolution) survey of the molecular gas reservoir across a the disk of a massive star ...
Schinnerer Eva +8 more
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Annual Review of Astronomy and Astrophysics, 2022 Spirals in galaxies have long been thought to be caused by gravitational instability in the stellar component of the disk, but discerning the precise mechanism had proved elusive. Tidal interactions, and perhaps bars, may provoke some spiral responses, but spirals in many galaxies must be self-excited.
Sellwood, Jerry A., Masters, Karen
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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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Dependence of stellar substructures in M31 type galaxy on satellite morphology in galaxy mergers [PDF]
Serbian Astronomical Journal, 2022 Stellar streams and shells are observed in halos of spiral galaxies. In this paper, we investigated the formation of these structures due to mergers between the host spiral galaxy and its dwarf satellite galaxies.
Milošević S.
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Planetary Nebulae and the Ionization of the Interstellar Medium in Galaxies
Frontiers in Astronomy and Space Sciences, 2022 We discuss the role of planetary nebulae and their progeny in galaxy context in terms of ionization of the galaxy interstellar medium. This regards ionized gas outside the disk of spiral galaxies, the diffuse ionized medium in spiral galaxies, and the ...
Grażyna Stasińska +2 more
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Universe, 2022 The rotational velocity curve, which is the circular velocity profile of the stars and gas in a spiral galaxy as a function of their distance from the galactic center, plays an important role in the kinematic and dynamic investigation of spiral galaxies.
Miroslava Vukcevic
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Lopsided spiral galaxies [PDF]
Physics Reports, 2009 The light distribution in the disks of many galaxies is non-axisymmetric or `lopsided' with a spatial extent much larger along one half of a galaxy than the other, as in M101. Recent near-IR observations show that lopsidedness is common. The stellar disks in nearly 30 % of galaxies have significant lopsidedness, greater than 10 % measured as the ...
Jog, Chanda J, Combes, Francoise
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The Identification of a Dusty Multiarm Spiral Galaxy at z = 3.06 with JWST and ALMA
The Astrophysical Journal Letters, 2022 Spiral arms serve crucial purposes in star formation and galaxy evolution. In this paper, we report the identification of “A2744-DSG- z 3,” a dusty, multiarm spiral galaxy at z = 3.059 using the James Webb Space Telescope (JWST) NIRISS imaging and grism ...
Yunjing Wu +15 more
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