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Related papers: Galactic Spiral Shocks with Thermal Instability

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The density wave theory predicted some physical offsets among different tracers of star formation. To test this prediction, here we compiled data on 40 galaxies searched observationally for a physical offset between spiral arm tracers, and…

Astrophysics of Galaxies · Physics 2019-11-21 Jacques P Vallee

By using $N$-body and hydro simulations, we study the formation and evolution of bars in galaxies with significant gas content focusing on the phenomenon of the buckling instability. The galaxies are initially composed of a spherical dark…

Astrophysics of Galaxies · Physics 2020-02-26 Ewa L. Lokas

The Gaia satellite revealed a remarkable spiral pattern ('phase spiral', PS) in the z-Vz phase-plane throughout the solar neighbourhood, where z and Vz are the displacement and velocity of a star perpendicular to the Galactic plane. As…

Astrophysics of Galaxies · Physics 2025-08-21 Thor Tepper-García , Joss Bland-Hawthorn , Timothy R. Bedding , Christoph Federrath , Oscar Agertz

We study the stability of a hot saturated gas coexisting with condensed particles in an optically thin medium. Such a situation may obtain downstream of a shock, at condensation fronts, or in vaporizing impacts. We show that the…

Earth and Planetary Astrophysics · Physics 2025-08-08 Kecheng Stephon Qian , Eugene Chiang

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…

Collisional self-interactions occurring in protostellar jets give rise to strong shocks, the structure of which can be affected by radiative cooling within the flow. To study such colliding flows, we use the AstroBEAR AMR code to conduct…

High Energy Astrophysical Phenomena · Physics 2022-12-13 R. N. Markwick , A. Frank , J. Carroll-Nellenback , B. Liu , E. G. Blackman , S. V. Lebedev , P. M. Hartigan

In this work, we have carried out a two-dimensional (2D) simulation of thermal instability (TI) in interstellar matter (ISM), considering it to be a weakly ionised inviscid plasma with radiation loss. We carry out the simulation using our…

Plasma Physics · Physics 2026-02-04 Hitendra Sarkar , Madhurjya P. Bora

One of the scenarios for the formation of grand-design spiral arms in disky galaxies involves their interactions with a satellite or another galaxy. Here we consider another possibility, where the perturbation is instead due to the…

Astrophysics of Galaxies · Physics 2016-12-28 Marcin Semczuk , Ewa L. Lokas , Andres del Pino

Using high-resolution {\sc Romulus} simulations, we explore the origin and evolution of the circumgalactic medium (CGM) in the region 0.1 $\leq \mathrm{R}/\mathrm{R}_\mathrm{500} \leq$ 1 around massive central galaxies in group-scale halos.…

A recent survey of the fine-structure excitation of neutral carbon reveals that the interstellar medium in the Galactic plane exhibits a thermal pressure, nT/k, that ranges from about 10^3 to 10^4 cm{-3}K from one location to the next, with…

Astrophysics · Physics 2008-11-26 Edward B. Jenkins

The existence of substellar cold H2 globules in planetary nebulae and the mere existence of comets suggest that the physics of cold interstellar gas might be much richer than usually envisioned. We study the case of a cold gaseous medium in…

Astrophysics of Galaxies · Physics 2016-08-08 Andreas Füglistaler , Daniel Pfenniger

Precipitation of cold gas due to thermal instability in both galaxy clusters and the circumgalactic medium may regulate AGN feedback. We investigate thermal instability in idealized simulations of the circumgalactic medium with a parameter…

Astrophysics of Galaxies · Physics 2024-10-08 Benjamin D. Wibking , G. Mark Voit , Brian W. O'Shea

We report systematic variations in the CO(2-1)/CO(1-0) line ratio (R) in M51. The ratio shows clear evidence for the evolution of molecular gas from the upstream interarm regions, passage into the spiral arms and back into the downstream…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 J. Koda , N. Scoville , T. Hasegawa , D. Calzetti , J. Donovan Meyer , F. Egusa , R. Kennicutt , N. Kuno , M. Louie , R. Momose , T. Sawada , K. Sorai , M. Umei

Thermal instability in the circum-galactic medium (CGM) can be responsible for the existence of cold clouds (e.g., high-velocity clouds) embedded in a hot diffuse medium (e.g., X-ray emitting gas). While many previous studies have analyzed…

Astrophysics of Galaxies · Physics 2025-12-24 Izumi Seno , Shu-ichiro Inutsuka , Jiro Shimoda

We present the first dynamically and thermally self-consistent calculations of fast adiabatically expanding gas flows from the Galactic disk into the halo. It is shown that in a hot plasma (T >= 10^6 K) with a high overpressure with respect…

Astrophysics · Physics 2007-05-23 Dieter Breitschwerdt , Thomas Schmutzler

We study the temperature structure of the intergalactic medium (IGM) using a large cosmological N-body/SPH simulation. We employ a two-temperature model for the thermal evolution of the ionized gas, in which the relaxation process between…

Astrophysics · Physics 2009-11-10 Naoki Yoshida , Steven Furlanetto , Lars Hernquist

We present gas and stellar kinematics of a high-resolution zoom-in cosmological chemodynamical simulation, which fortuitously captures the formation and evolution of a star-forming barred spiral galaxy, from redshift $z\sim3$ to $z\sim2$ at…

Astrophysics of Galaxies · Physics 2019-08-07 Fiorenzo Vincenzo , Chiaki Kobayashi , Tiantian Yuan

We examine the development of a transient spiral arm in a disk galaxy made up of both gas and stars. To this end we have performed numerical simulations in a shearing sheet (basically a rectangular patch of a disc) that contains gas in the…

Astrophysics · Physics 2007-05-23 Markus Demleitner

The gas dynamics in the Galactic disc is modeled by releasing an initially axisymmetric SPH component in a completely self-consistent and symmetry-free 3D N-body simulation of the Milky Way in which the stellar components display a…

Astrophysics · Physics 2007-05-23 R. Fux

Acceleration can change the ionization of X-ray irradiated gas to the point that the gas becomes thermally unstable. Cloud formation, the expected outcome of thermal instability (TI), will be suppressed in a dynamic flow, however, due to…

Astrophysics of Galaxies · Physics 2022-06-08 Tim Waters , Daniel Proga , Randall Dannen , Sergei Dyda