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The dynamics of temperature fluctuations of a gas of Brownian particles in local equilibrium with a nonequilibrium heat bath, are described using an approach consistent with Boltzmann-Gibbs statistics (BG). We use mesoscopic nonequilibrium…

Statistical Mechanics · Physics 2009-11-13 R. F. Rodriguez , I. Santamaria-Holek

The polarization spectrum, or wavelength dependence of the polarization fraction, of interstellar dust emission provides important insights into the grain alignment mechanism of interstellar dust grains. We investigate the far-infrared…

We consider a dynamical system subjected to weak but adiabatically slow fluctuations of external origin. Based on the ``adiabatic following'' approximation we carry out an expansion in \alpha/|\mu|, where \alpha is the strength of…

Statistical Mechanics · Physics 2009-10-31 S. K. Banik , D. S. Ray

Thermal fluctuations in the magnetization of interstellar grains will produce magnetic dipole emission at frequencies below ~100 GHz. We show how to calculate absorption and emission from small particles composed of magnetic materials. The…

Astrophysics · Physics 2009-10-30 B. T. Draine , A. Lazarian

The distinguishing feature of the evolution of close binary stars is the role played by the mass exchange between the component stars. Whether the mass transfer is dynamically stable is one of the essential questions in binary evolution. In…

Solar and Stellar Astrophysics · Physics 2020-09-02 Hongwei Ge , Ronald F Webbink , Xuefei Chen , Zhanwen Han

Scattering and absorption of X-rays by interstellar dust is calculated for a model consisting of carbonaceous grains and amorphous silicate grains. The calculations employ realistic dielectric functions with structure near X-ray absorption…

Astrophysics · Physics 2009-11-10 B. T. Draine

In the study of evolution equations, the method of adiabatic approximation is an essential tool to reduce an infinite-dimensional dynamical system to a simpler, possibly finite-dimensional one. In this paper, we formulate a generic scheme…

Analysis of PDEs · Mathematics 2022-03-09 Jingxuan Zhang

We formulate an adiabatic approximation for the imaginary-time Schroedinger equation. The obtained adiabatic condition consists of two inequalities, one of which coincides with the conventional adiabatic condition for the real-time…

Quantum Physics · Physics 2015-08-07 Kazuya Kaneko , Hidetoshi Nishimori

The composite grain is made up of a host silicate spheroid and graphite inclusions. The extinction efficiencies of the composite spheroidal grains for three axial ratios are computed using the discrete dipole approximation (DDA). The…

Astrophysics · Physics 2009-06-23 D. B. Vaidya , Ranjan Gupta , T. P. Snow

Polarized extinction and emission from dust in the interstellar medium (ISM) are hard to interpret, as they have a complex dependence on dust optical properties, grain alignment and magnetic field orientation. This is particularly true in…

Astrophysics of Galaxies · Physics 2017-05-24 Lapo Fanciullo , Vincent Guillet , François Boulanger , Anthony Jones

Interstellar dust grains do not have a single well-defined origin. Stars are demonstrably dust producers, but also efficient destroyers of cosmic dust. Dust destruction in the ISM is believed to be the result of SN shocks hitting the…

Astrophysics of Galaxies · Physics 2016-06-24 Lars Mattsson

We have computed wind models with time-dependent dust formation and grain-size dependent opacities, where (1) the problem is simplified by assuming a fixed dust-grain size, and where (2) the radiation pressure efficiency is approximated…

Solar and Stellar Astrophysics · Physics 2010-10-04 Lars Mattsson , Susanne Höfner

A common goal in observational research is to estimate marginal causal effects in the presence of confounding variables. One solution to this problem is to use the covariate distribution to weight the outcomes such that the data appear…

Methodology · Statistics 2020-08-18 Kevin P. Josey , Elizabeth Juarez-Colunga , Fan Yang , Debashis Ghosh

We present a new approach to coarse-graining of variables describing dust flow in GR. It is based on assigning quasi-local shear, twist and expansion to 2-dimensional surfaces with the help of isometric embeddings into the 3-dimensional…

General Relativity and Quantum Cosmology · Physics 2015-05-14 Mikolaj Korzynski

In this analysis we illustrate how the relatively new emission mechanism known as spinning dust can be used to characterize dust grains in the interstellar medium. We demonstrate this by using spinning dust emission observations to…

Variations in polarization efficiency (p/A) of interstellar grains as a function of environment place vital constraints on models for the mechanism of their alignment. We use polarimetry of background field stars to investigate alignment in…

Astrophysics · Physics 2009-10-28 P. A. Gerakines , D. C. B. Whittet

A composite dust grain model which simultaneously explains the observed interstellar extinction, polarization, IR emission and the abundance constraints, is required. We present a composite grain model, which is made up of a host silicate…

Solar and Stellar Astrophysics · Physics 2013-10-02 Nisha Katyal , Ranjan Gupta , D. B. Vaidya

Adiabatic control is a fundamental technique for manipulating quantum systems, guided by the quantum adiabatic theorem, which ensures suppressed nonadiabatic transitions under slow parameter variations. Quantum annealing, a heuristic…

Quantum Physics · Physics 2025-01-22 Yuta Shingu , Takuya Hatomura

Context. Observations at sub-millimeter and mm wavelengths will in the near future be able to resolve the radial dependence of the mm spectral slope in circumstellar disks with a resolution of around a few AU at the distance of the closest…

Solar and Stellar Astrophysics · Physics 2010-07-20 T. Birnstiel , L. Ricci , F. Trotta , C. P. Dullemond , A. Natta , L. Testi , C. Dominik , T. Henning , C. W. Ormel , A. Zsom

We compute the evolution of interstellar dust in a hydrodynamic simulation of an isolated disc galaxy. We newly implement the evolution of full grain size distribution by sampling 32 grid points on the axis of the grain radius. We solve it…

Astrophysics of Galaxies · Physics 2020-01-08 Shohei Aoyama , Hiroyuki Hirashita , Kentaro Nagamine