Results 1 to 10 of about 67,646 (268)
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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Measuring the Spin of Spiral Galaxies [PDF]
The Astrophysical Journal, 2006 We compute the angular momentum, the spin parameter and the related distribution function for Dark Matter halos hosting a spiral galaxy. We base on scaling laws, inferred from observations, that link the properties of the galaxy to those of the host halo; we further assume that the Dark Matter has the same total specific angular momentum of the baryons.
C. Tonini +7 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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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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SUPERLUMINOUS SPIRAL GALAXIES [PDF]
The Astrophysical Journal, 2016 ABSTRACT We report the discovery of spiral galaxies that are as optically luminous as elliptical brightest cluster galaxies, with r-band monochromatic luminosity L r = 8–14L* (4.3–7.5 × 1044 erg s−1).
Patrick M. Ogle +3 more
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Reanalysis of the Spin Direction Distribution of Galaxy Zoo SDSS Spiral Galaxies
Advances in Astronomy, 2023 The distribution of the spin directions of spiral galaxies in the Sloan Digital Sky Survey has been a topic of debate in the past two decades, with conflicting conclusions reported even in cases where the same data were used.
Darius Mcadam, Lior Shamir
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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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Discovery of a Planar Black Hole Mass Scaling Relation for Spiral Galaxies
The Astrophysical Journal Letters, 2023 Supermassive black holes (SMBHs) are tiny in comparison to the galaxies they inhabit, yet they manage to influence and coevolve along with their hosts.
Benjamin L. Davis, Zehao Jin
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Galaxy Zoo:dust in spiral galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2011 We investigate the effect of dust on spiral galaxies by measuring the inclination dependence of optical colours for 24 276 well-resolved Sloan Digital Sky Survey (SDSS) galaxies visually classified via the Galaxy Zoo project. We find clear trends of reddening with inclination which imply a total extinction from face-on to edge-on of 0.7, 0.6, 0.5 and 0.
Masters, Karen L. +14 more
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