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Related papers: Pitch angle variations in spiral galaxies

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As a result of our statistical study of 540 edge-on galaxies, we present here the images and preliminary statistical analysis of a sub-sample of 60 galaxies, that were selected to be S-type warped spirals. Computing the average volumic…

Astrophysics · Physics 2009-10-31 Vladimir Reshetnikov , Francoise Combes

We present a numerical study of the properties of the stellar velocity distribution in stellar discs which have developed a saturated, two-armed spiral structure. We follow the growth of the spiral structure deeply into the non-linear…

Astrophysics · Physics 2009-11-13 E. I. Vorobyov , Ch. Theis

We describe a system for the automatic quantification of structure in spiral galaxies. This enables translation of sky survey images into data needed to help address fundamental astrophysical questions such as the origin of spiral…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-04 Darren Davis , Wayne Hayes

Context: Because of our viewing point within the Galactic disc, it is extremely difficult to observe the spiral structure of the Milky Way. Aims: To clarify the structure of the Galaxy by re-examination of gas distributions and data from…

Astrophysics of Galaxies · Physics 2015-06-04 Charles Francis , Erik Anderson

We investigate the photometric properties of 456 bright galaxies using imaging data recorded during the commissioning phase of the Sloan Digital Sky Survey (SDSS). Morphological classification is carried out by correlating results of…

Astrophysics · Physics 2009-07-09 K. Shimasaku , M. Fukugita , M. Doi , M. Hamabe , T. Ichikawa , S. Okamura , M. Sekiguchi , N. Yasuda

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…

Astrophysics of Galaxies · Physics 2022-10-26 George Contopoulos

The generation of spiral arms and the mechanisms controlling their properties within a realistic cosmological framework - the complete understanding is still beyond our grasp. Using a statistically significant sample of Milky Way- and…

Astrophysics of Galaxies · Physics 2025-10-31 Soumavo Ghosh , Elena D'Onghia

Spiral arms play a central role in disc galaxies, but their dynamical nature remains a long-standing open question. Azimuthal offsets between molecular gas and star formation are expected if gas crosses spiral arms, as predicted by…

The dynamical nature and formation mechanism(s) of galactic spiral arms remain long-standing problems in astrophysics. Most theoretical work is based on analytic calculations or idealised simulations, which has yielded several theories of…

We expand our pervious numerical study of the properties of the stellar velocity distribution within the disk of a two-armed spiral galaxy by considering spiral stellar density waves with different global Fourier amplitudes, C_2. We confirm…

Astrophysics · Physics 2009-11-13 E. I. Vorobyov , Christian Theis

Spiral arms are distinctive features of many circumstellar disks, observed in scattered light, which traces the disk surface, millimeter dust emission, which probes the disk midplane, as well as molecular emission. The two leading…

Earth and Planetary Astrophysics · Physics 2021-03-24 Hans Baehr , Zhaohuan Zhu

(abridged) Measures of the HI properties of a galaxy are among the most sensitive interaction diagnostic at our disposal. We report here on a study of HI profile asymmetries (e.g., lopsidedness) in a sample of some of the most isolated…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 D. Espada , L. Verdes-Montenegro , W. K. Huchtmeier , J. Sulentic , S. Verley , S. Leon , J. Sabater

We consider the possible pattern of the overall spiral structure of the Galaxy, using data on the distribution of neutral (atomic), molecular, and ionized hydrogen, on the base of the hypothesis of the spiral structure being symmetric, i.e.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Yuri N. Efremov

As galaxies evolve over time, the orbits of their constituent stars are expected to change in size and shape, moving stars away from their birth radius. Radial gas flows are also expected. Spiral arms and bars in galaxies are predicted to…

Astrophysics of Galaxies · Physics 2026-04-21 M. E. Wisz , Karen L. Masters , Kathryne J. Daniel , David V. Stark , Francesco Belfiore

The mean Galactocentric radial velocities $\langle v_{R}\rangle(R,\varphi)$ of luminous red giant stars within the mid-plane of the Milky Way reveal a spiral signature, which could plausibly reflect the response to a non-axisymmetric…

Using imaging data from the SDSS survey, we present the g' and r' radial stellar light distribution of a complete sample of ~90 face-on to intermediate inclined, nearby, late-type (Sb-Sdm) spiral galaxies. The surface brightness profiles…

Astrophysics · Physics 2009-11-11 M. Pohlen , I. Trujillo

This paper is the first part in our series on the influence of tidal interactions and minor mergers on the radial and vertical disk structure of spiral galaxies. We report on the sample selection, our observations, and data reduction.…

Astrophysics · Physics 2010-01-25 U. Schwarzkopf , R. -J. Dettmar

We run N-body smoothed particle hydrodynamics (SPH) simulations of a Milky Way sized galaxy. The code takes into account hydrodynamics, self-gravity, star formation, supernova and stellar wind feedback, radiative cooling and metal…

Astrophysics of Galaxies · Physics 2015-06-04 Robert J. J. Grand , Daisuke Kawata , Mark Cropper

A dataset of 126,501 spiral galaxies taken from Sloan Digital Sky Survey was used to analyze the large-scale galaxy handedness in different regions of the local universe. The analysis was automated by using a transformation of the galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Lior Shamir