The dynamics of stars around spiral arms

By R. Grand, Daisuke Kawata, M. Cropper. 2011

158 citations recorded by the source corpus.

Spiral density wave theory attempts to describe the spiral pattern in spiral galaxies in terms of a long-lived wave structure with a constant pattern speed in order to avoid the winding dilemma. The pattern is consequently a rigidly rotating, long-lived feature. We run N-body simulations of a giant disc galaxy consisting of a pure stellar disc and a static dark matter halo, and find that the spiral arms are transient features whose pattern speeds decrease with radius in such a way that the pattern speed is almost equal to the rotation curve of the galaxy. We trace particle motion around the spiral arms. We show that particles from behind and in front of the spiral arm are drawn towards and join the arm. Particles move along the arm in the radial direction and we find a clear trend that they migrate towards the outer (inner) radii on the trailing (leading) side of the arm. Our simulations demonstrate that because the spiral arm feature is corotating, the particles continue to be accelerated (decelerated) by the spiral arm for long periods, which leads to strong and efficient migration, at all radii in the disc.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/8ab74fd685e84b1edb6da167167934b30fc5cc86

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Citations in the corpus

Dawes Review 4: Spiral Structures in Disc Galaxies (2014, methodology): “The stars oscillate along the curve of circular motion by undergoing change in terms of both angular momentum and energy (Sellwood & Binney 2002; Grand et al. 2012a; Roškar et al. 2012; Baba et al. 2013).”
Measuring Radial Orbit Migration in the Galactic Disk (2018, background): “…the angular momentum (and hence the size of the orbit) of any star may change by of the order of unity over timescales as short as a few Gyr (Grand et al. 2012, 2016; Kubryk et al. 2013), the detail depending on the properties of the non-axisymmetric structures, such as their pattern speeds…”
Radial migration does little for Galactic disc thickening (2012, background): “…to exist in both observation (Elmegreen et al., 1992; Rix and Zaritsky, 1995; Meidt et al., 2009) and simulations (e.g., Masset and Tagger 1997; Quillen et al. 2011; Minchev et al. 2012a; Grand et al. 2012; Roškar et al. 2012), therefore this heating process may be ubiquitous in disc galaxies.”
Estimating stellar birth radii and the time evolution of Milky Way’s ISM metallicity gradient (2018, background): “Grand et al. (2012) showed that the spirals seen in disk morphology (as opposed to the power spectrum) in their N-body simulations were moving close to corotation at all radii, which was interpreted by Comparetta & Quillen (2012) as the effect of long-lived multiple modes (Tagger et al. 1987;…”
SELF-PERPETUATING SPIRAL ARMS IN DISK GALAXIES (2012, background): “However, recent investigations using numerical simulations of stellar disks have challenged this claim and and argue that the arms might be material structures (Grand et al. 2012).”
Impacts of a flaring star-forming disc and stellar radial mixing on the vertical metallicity gradient (2016, methodology): “We initially set up an isolated disc galaxy which consists of stellar discs, with no bulge component, in a static dark matter halo potential (Rahimi & Kawata 2012; Grand et al. 2012).”
Stellar population gradients in galaxy discs from the CALIFA survey - The influence of bars (2014, background): “…literature over the past few years (Sellwood & Binney 2002; Roškar et al. 2008a,b; Berentzen et al. 2007; Minchev & Famaey 2010; Minchev et al. 2011, 2012a,b, 2014a,b; Grand et al. 2012a,b; Comparetta & Quillen 2012; Di Matteo et al. 2013; Brunetti et al. 2011; Shevchenko 2011; Kubryk et al. 2013).”
Constraining the Milky Way assembly history with Galactic Archaeology (2016, methodology): “A number of works using Nbody and N-body/SPH simulations (e.g., Grand et al. 2012; Minchev et al. 2011; Roškar et al. 2008) have confirm that migration always takes place in numerical galactic discs.”
THE EFFECT OF RADIAL MIGRATION ON GALACTIC DISKS (2014, background): “…on direct numerical simulation, some studies are based on the response of equilibrium disk models to transient spiral modes (Sellwood & Binney 2002; Grand et al. 2012; Solway et al. 2012; Sellwood & Carlberg 2014) or to the tidal perturbation of a massive satellite (Kazantzidis et al. 2008;…”
Vertical disc heating in Milky Way-sized galaxies in a cosmological context (2015, background): “…with the systematic radial motion of star particles as a response to continual tangential gravitational forces supplied by transient spiral arms seen in isolated simulations (Grand et al. 2012a,b, 2014), and indicative that spiral arms and a bar drive radial migration in our suite of simulations.”