Results 61 to 70 of about 12,684 (325)
IEEE Access, 2022 The analysis of Archimedean spiral slots using the theory of characteristic modes is presented in this article. Purely magnetic characteristic modes are used to study the behavior of a spiral slot etched in an infinite ground plane.
Pallavi Sharma, Jennifer T. Bernhard
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Highly Embedded 8 μm cores of Star Formation in the Spiral Arms and Filaments of 15 Nearby Disk Galaxies [PDF]
Astrophysical Journal Supplement Series, 2019 Spitzer Space Telescope observations of 15 spiral galaxies show numerous dense cores at 8 μm that are revealed primarily in unsharp mask images. The cores are generally invisible in optical bands because of extinction, and they are also indistinct at 8 ...
B. Elmegreen, D. Elmegreen
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The evolution of pitch angles of spiral arms [PDF]
Monthly notices of the Royal Astronomical Society, 2019 In spiral galaxies, the pitch angle, α, of the spiral arms is often proposed as a discriminator between theories for the formation of the spiral structure.
J. Pringle, C. Dobbs
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Spiral arms across stellar populations in simulations via the local dimension method
Astronomy & AstrophysicsContext. The origin and nature of spiral arms remain unclear. Star-forming regions and young stars are generally strongly associated with the spiral structure, but there are few quantitative predictions from simulations about the contribution of stars of
Ardèvol J. +5 more
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Spiral arms and instability within the AFGL 4176 mm1 disc [PDF]
Astronomy & Astrophysics, 2019 We present high-resolution (30 mas or 130 au at 4.2 kpc) Atacama Large Millimeter/submillimeter Array observations at 1.2 mm of the disc around the forming O-type star AFGL 4176 mm1.
K. Johnston +9 more
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Theoretical Model of Spiral Rain Clusters and Analysis of Their Horizontal Structure Equation
Atmosphere, 2017 Rain clusters are mesoscale disaster weather systems, and some of rain clusters have spiral structures. In this paper, a theoretical model of spiral rain cluster is established under pseudo-adiabatic approximation, and its horizontal structure equation ...
Jie Yu, Jiquan Zhang, Ming Zhang
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SELF-PERPETUATING SPIRAL ARMS IN DISK GALAXIES [PDF]
The Astrophysical Journal, 2013 16 pages, 11 figures, APJ accepted. Interpretation and conclusions unchanged.
D’Onghia, Elena +2 more
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ALMA Reveals Potential Evidence for Spiral Arms, Bars, and Rings in High-redshift Submillimeter Galaxies [PDF]
, 2018 We present subkiloparsec-scale mapping of the 870 mu m ALMA continuum emission in six luminous (LIR similar to 5 x 10(12 )L(circle dot)) submillimeter galaxies (SMGs) from the ALESS survey of the Extended Chandra Deep Field South.
J. Hodge +22 more
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Spiral Arms in Disks: Planets or Gravitational Instability? [PDF]
Astrophysical Journal, 2018 Spiral arm structures seen in scattered-light observations of protoplanetary disks can potentially serve as signposts of planetary companions. They can also lend unique insights into disk masses, which are critical in setting the mass budget for planet ...
Ruobing 若冰 Dong 董 +2 more
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, 2022 The most important theory of the spiral arms of galaxies is the density wave theory based on the Lin-Shu dispersion relation. However, the density waves move with the group velocity towards the inner Lindblad resonance and tend to disappear. Various mechanisms to replenish the spiral waves have been proposed.
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