How do different spiral arm models impact the ISM and GMC population?

  title={How do different spiral arm models impact the ISM and GMC population?},
  author={Alex R. Pettitt and Clare L. Dobbs and Junichi Baba and D. Colombo and Ana Duarte-Cabral and Fumi Egusa and Asao Habe},
  journal={Monthly Notices of the Royal Astronomical Society},
The nature of galactic spiral arms in disc galaxies remains elusive. Regardless of the spiral model, arms are expected to play a role in sculpting the star-forming interstellar medium. As such, different arm models may result in differences in the structure of the interstellar medium and molecular cloud properties. In this study we present simulations of galactic discs subject to spiral arm perturbations of different natures. We find very little difference in how the cloud population or gas… 

Spiral Structure Boosts Star Formation in Disk Galaxies

We investigate the impact of spiral structure on global star formation using a sample of 2226 nearby bright disk galaxies. Examining the relationship between spiral arms, star formation rate (SFR),

Quantifying the fine structures of disk galaxies with deep learning: Segmentation of spiral arms in different Hubble types

  • K. Bekki
  • Physics
    Astronomy & Astrophysics
  • 2021
Context. Spatial correlations between spiral arms and other galactic components such as giant molecular clouds and massive OB stars suggest that spiral arms can play vital roles in various aspects of

Large-scale Hydrodynamical Shocks as the Smoking-gun Evidence for a Bar in M31

The formation and evolutionary history of M31 are closely related to its dynamical structures, which remain unclear due to its high inclination. Gas kinematics could provide crucial evidence for the

Arm Tangents and the Spiral Structure of the Milky Way—The Age Gradient

  • J. Vallée
  • Physics
    International Journal of Astronomy and Astrophysics
  • 2021
From the Sun, a look at the edge of each spiral arm in our Milky Way (seen tangentially, along the line of sight) can yield numerous insights. Using different arm tracers (dust, masers, synchrotron

Giant molecular cloud catalogues for PHANGS-ALMA: methods and initial results

We present improved methods for segmenting CO emission from galaxies into individual molecular clouds, providing an update to the cprops algorithms presented by Rosolowsky & Leroy. The new code

A low density wave's spiral pattern speed, from the tracer separations (age gradient) across a spiral arm in the Milky Way

We observe the density wave’s angular pattern speed Ωp to be near 12-17 km/s/kpc, by the separation between a typical optical HII region (from the spiral arm’s dust lane) and using a HII-evolution



On the Dynamical Relevance of Galaxy Spiral Arm Evolution. I. Arm Density Structure

We explore the spiral arm structural properties in a large variety of simulated galaxy systems. We study spiral arms arising from isolated barred and unbarred galaxies, as well as from interactions

Gas and stellar spiral structures in tidally perturbed disc galaxies

Tidal interactions between disc galaxies and low mass companions are an established method for generating galactic spiral features. In this work we present a study of the structure and dynamics of

The Impact of Galactic Disc Environment on Star-Forming Clouds

We explore the effect of different galactic disc environments on the properties of star-forming clouds through variations in the background potential in a set of isolated galaxy simulations. Rising,

The changing GMC population in galaxy interactions

With the advent of modern observational efforts providing extensive giant molecular cloud catalogues, understanding the evolution of such clouds in a galactic context is of prime importance. While

Bars and spirals in tidal interactions with an ensemble of galaxy mass models

We present simulations of the gaseous and stellar material in several different galaxy mass models under the influence of different tidal fly-bys to assess the changes in their bar and spiral

Do giant molecular clouds care about the galactic structure

We investigate the impact of galactic environment on the properties of simulated giant molecular clouds formed in a M83-type barred spiral galaxy. Our simulation uses a rotating stellar potential to

Gaseous spiral structure and mass drift in spiral galaxies

We use hydrodynamic simulations to investigate nonlinear gas responses to an imposed stellar spiral potential in disk galaxies. The gaseous medium is assumed to be infinitesimally thin, isothermal,


We test whether the spiral patterns apparent in many large disk galaxies should be thought of as dynamical features that are stationary in a corotating frame for ≳ tdyn, as implied by the density

Search for star cluster age gradients across spiral arms of three LEGUS disc galaxies

One of the main theories for explaining the formation of spiral arms in galaxies is the stationary density wave theory. This theory predicts the existence of an age gradient across the arms. We use

The properties of the interstellar medium in disc galaxies with stellar feedback

We perform calculations of isolated disc galaxies to investigate how the properties of the interstellar medium (ISM), the nature of molecular clouds and the global star formation rate depend on the