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Related papers: New Developments in Spiral Structure Theory

200 papers

Context: Resonances in the stellar orbital motion under perturbations from spiral arms structure play an important role in the evolution of the disks of spiral galaxies. The epicyclic approximation allows the determination of the…

Astrophysics of Galaxies · Physics 2016-10-20 Tatiana A. Michtchenko , Ronaldo S. S. Vieira , Douglas A. Barros , Jacques R. D. Lépine

We present a map of the spiral structure of the Galaxy, as traced by molecular CS emission associated with IRAS sources which are believed to be compact HII regions. The CS line velocities are used to determine the kinematic distances of…

Astrophysics of Galaxies · Physics 2015-05-20 J. R. D. Lepine , A. Roman-Lopes , Zulema Abraham , T. C. Junqueira , Yu. N. Mishurov

Spiral wave patterns observed in models of cardiac arrhythmias and chemical oscillations develop alternans and stationary line defects, which can both be thought of as period-doubling instabilities. These instabilities are observed on…

Dynamical Systems · Mathematics 2019-05-30 Stephanie Dodson , Bjorn Sandstede

This two-part review summarizes interstellar turbulence and its implications. The first part begins with diagnostics and energy sources. Turbulence theory is considered in detail, including the basic fluid equations, solenoidal and…

Astrophysics · Physics 2008-11-26 Bruce G. Elmegreen , John Scalo

Spiral patterns are important agents of galaxy evolution. In this review, I describe how the redistribution of angular momentum by recurrent transient spiral patterns causes the random speeds of stars to rise over time, metallicity…

Astrophysics · Physics 2008-03-14 J. A. Sellwood

Spiral wave, whose rotation center can be regarded as a point defect, widely exists in various two dimensional excitable systems. In this paper, by making use of \emph{Duan's topological current theory}, we obtain the charge density of…

Pattern Formation and Solitons · Physics 2009-05-06 Ji-Rong Ren , Tao Zhu , Shu-Fan Mo

We derive a simple, accurate, non-linear, global equation governing spiral density waves in thin, non-self-gravitating, inviscid accretion discs. These discs may have any slowly varying surface density or temperature profile. For specific…

Earth and Planetary Astrophysics · Physics 2025-12-15 Joshua J. Brown , Gordon I. Ogilvie

It is discussed that the formation of the spiral galaxies is driven by the cosmic background rotation, not a result of an isolated evolution proposed by the density wave theory. To analyze the motions of the galaxies, a simple double…

Astrophysics of Galaxies · Physics 2018-02-20 Zexin Cao , Ling Liu , Tingting Zheng

Theories of spiral structure traditionally separate into tight-winding Lin-Shu spiral density waves and the swing-amplified material patterns of Goldreich & Lynden-Bell and Julian & Toomre. In this paper we consolidate these two types of…

Astrophysics of Galaxies · Physics 2023-12-06 Sharon E. Meidt , Arjen van der Wel

We describe the structure and composition of six major stellar streams in a population of 20 574 local stars in the New Hipparcos Reduction with known radial velocities. We find that, once fast moving stars are excluded, almost all stars…

General Physics · Physics 2010-01-15 Charles Francis , Erik Anderson

We investigate the formation of substructure in spiral galaxies using global MHD simulations, including gas self-gravity. Our models extend previous local models by Kim and Ostriker (2002) by including the full effects of curvilinear…

Astrophysics · Physics 2011-02-11 Rahul Shetty , Eve C. Ostriker

The numerical simulation of turbulence in stars has led to a rich set of possibilities regarding stellar pulsations, asteroseismology, thermonuclear yields, and formation of neutron stars and black holes. The breaking of symmetry by…

Solar and Stellar Astrophysics · Physics 2016-10-05 W. David Arnett , Casey Meakin

The first results of the observational program of the study of 2D-kinematics in double-barred galaxies are presented. We show that, for the main part of the sample, the inner bars do not affect the circumnuclear stellar kinematics.…

Astrophysics · Physics 2007-05-23 A. V. Moiseev , J. R. Valdes , V. H. Chavushyan

We study a heretofore ignored class of spiral patterns for oscillatory media as characterized by the complex Landau-Ginzburg model. These spirals emerge from modulating the growth rate as a function of $r$, thereby turning off the…

Pattern Formation and Solitons · Physics 2017-08-02 David A. Kessler , Herbert Levine

Planetary rings sustain a continual bombardment of hypervelocity meteoroids that erode the surfaces of ring particles on time scales of 10^5 - 10^7 years. The debris ejected from such impacts re-accretes on to the ring, though often at a…

Earth and Planetary Astrophysics · Physics 2015-06-11 Henrik Latter , Gordon Ogilvie , Marie Chupeau

This paper presents a detailed analysis of two-armed spiral structure in a sample of galax- ies from the Spitzer Infrared Nearby Galaxies Survey (SINGS), with particular focus on the relationships between the properties of the spiral…

Astrophysics of Galaxies · Physics 2015-06-23 S. Kendall , C. Clarke , R. C. Kennicutt

Gaia recently revealed a two-armed spiral pattern in the vertical phase-space distribution of the inner Galactic disk (guiding radius $R_\textrm{g} \sim 6.2$ kpc), indicating that some non-adiabatic perturbation symmetric about the…

Astrophysics of Galaxies · Physics 2025-10-22 Rimpei Chiba , Neige Frankel , Chris Hamilton

Results are presented of numerical simulations of normal isolated late type spiral galaxies. Specifically the galaxy NGC 628 is used as a template. The method employs a TREESPH code including stellar particles, gas particles, cooling and…

Astrophysics · Physics 2009-11-07 Roelof Bottema

Scalar-tensor~(ST) theories of gravity are natural phenomenological extensions to general relativity. Although these theories are severely constrained both by solar system experiments and by binary pulsar observations, a large set of ST…

General Relativity and Quantum Cosmology · Physics 2016-02-10 Carlos Palenzuela , Steve Liebling

Spiral waves in active media react to small perturbations as particle-like objects. Here we apply the asymptotic theory to the interaction of spiral waves with a localized inhomogeneity, which leads to a novel prediction: drift of the…

Pattern Formation and Solitons · Physics 2010-01-25 V. N. Biktashev , D. Barkley , I. V. Biktasheva
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