Related papers: Fluctuations in Isothermal Spheres
We study, using $N$-body simulation, the shape evolution in gravitational collapse of cold uniform spherical system. The central interest is on how the deviation from spherical symmetry depends on particle number $N$. By revisit of the…
We present the statistical analysis of X-ray surface brightness and gas density fluctuations in cool cores of ten, nearby and bright galaxy clusters that have deep Chandra observations and show observational indications of radio-mechanical…
We investigate the stability of bounded self-gravitating systems in the canonical ensemble by using a thermodynamical approach. Our study extends the earlier work of Padmanabhan [Astrophys. J. Supp. 71, 651 (1989)] in the microcanonical…
Nuclear rings at centers of barred galaxies exhibit strong star formation activities. They are thought to undergo gravitational instability when sufficiently massive. We approximate them as rigidly-rotating isothermal objects and…
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…
We study the thermal fluctuations of vortex positions in small vortex clusters in a harmonically trapped rotating Bose-Einstein condensate. It is shown that the order-disorder transition of two-shells clusters occurs via the decoupling of…
We complete the existing literature on the structure and stability of polytropic gas spheres reported in the classical monograph of Chandrasekhar (1942). For isolated polytropes with index $1<n<5$, we provide a new, alternative, proof that…
Large-amplitude isothermal fluctuations in the dark matter energy density, parameterized by $\Phi\equiv\delta\rhodm/\rhodm$, are studied within the framework of a spherical collapse model. For $\Phi \ga 1$, a fluctuation collapses in the…
High-resolution simulations of the cooling regions of spherically symmetric supernova remnants demonstrate a strong radiative instability. This instability, whose presence is dependent on the shock velocity, causes large-amplitude…
Heat input roughly balances radiative cooling in the gaseous cores of galaxy clusters even when the central cooling time is short, implying that cooling triggers a feedback loop that maintains thermal balance. Furthermore, cores with short…
Fluctuations are a key property of both classical and quantum systems. While the fluctuations are well understood for many quantum systems at zero temperature, the case of an interacting quantum system at finite temperature still poses…
Thermal instability (TI) is a trigger mechanism, which can explain the formation of small condensations through some regions of the interstellar clouds. The instability criterion for flat geometry approximations has been investigated in…
We study the thermal equilibrium and stability of isobaric, spherical structures having a radiation source located at its center. The thermal conduction coefficient, external heating and cooling rates are represented as power laws of the…
Density fluctuations resulting from spinodal decomposition in a non-equilibrium first-order chiral phase transition are explored. We show that such instabilities generate divergent fluctuations of conserved charges along the isothermal…
We study particle clustering in a temperature stratified turbulence with small finite correlation time. It is shown that the temperature stratified turbulence strongly increases the degree of compressibility of particle velocity field. This…
We investigate a phase separation instability that occurs in a system of nearly elastically colliding hard spheres driven by a thermal wall. If the aspect ratio of the confining box exceeds a threshold value, granular hydrostatics predict…
It is usually expected and observed that non-integrable isolated quantum systems thermalize. However, for some non-integrable spin chain models, in a numerical study, initial states with oscillations that persisted for some time were found…
Using controlled numerical N-body experiments, we show how, in the collapse dynamics of an initially cold and uniform distribution of particles with a generic asymmetric shape, finite $N$ fluctuations and perturbations induced by the…
The question of how and which physical observables or thermodynamic parameters can best predict the onset of a possible phase transition in the inner crust of neutron stars remains largely unresolved. Using semiclassical Monte Carlo…
Quantum systems are typically characterized by the inherent fluctuation of their physical observables. Despite this fundamental importance, the investigation of the fluctuations in interacting quantum systems at finite temperature continues…