English
Related papers

Related papers: Overview of Grain Models

200 papers

There has been significant recent progress in observational cosmology. This, in turn, has provided an unprecedented picture of the early universe and its evolution. In this review I will present a (biased) view of how one can use these…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Raul Jimenez

Microstructural evolution in structural materials is known to occur in response to mechanical loading and can often accommodate substantial plastic deformation through the coupled motion of grain boundaries (GBs). This can produce desirable…

Mesoscale and Nanoscale Physics · Physics 2025-06-06 Daniel Bugas , Brandon Runnels

Interstellar dust grain growth in dense clouds and protoplanetary disks, even moderate, affects the observed interstellar ice profiles as soon as a significant fraction of dust grains is in the size range close to the wave vector at the…

Astrophysics of Galaxies · Physics 2022-10-26 Emmanuel Dartois , Jennifer A. Noble , Nathalie Ysard , Karine Demyk , Marin Chabot

This study proposes a new analytical model for grain boundary pinning by second phase particles in two-dimensional polycrystals. This approach not only considers how particles impede grain growth, but also elucidates their role in…

Materials Science · Physics 2024-04-23 Madeleine Bignon , Marc Bernacki

In the surface layers of late-type stars, stellar convection is manifested with its typical granulation pattern due to the presence of convective motions. The resulting photospheric up- and downflows leave imprints in the observed spectral…

Solar and Stellar Astrophysics · Physics 2014-05-30 Zazralt Magic , Martin Asplund

Interstellar abundance determinations from fits to X-ray absorption edges often rely on the incorrect assumption that scattering is insignificant and can be ignored. We show instead that scattering contributes significantly to the…

High Energy Astrophysical Phenomena · Physics 2016-02-05 John A. Hoffman , Bruce T. Draine

The grain boundary (GB) energy has a profound influence on the grain growth and properties of polycrystalline metals. Here, we show that the energy of a GB, normalized by the bulk cohesive energy, can be described purely by four geometric…

Materials Science · Physics 2022-01-31 Weike Ye , Hui Zheng , Chi Chen , Shyue Ping Ong

Sub-millimetre observations suggest that the filaments of interstellar clouds have rather uniform widths and can be described with the so-called Plummer profiles. The shapes of the filament profiles are linked to their physical state.…

Astrophysics of Galaxies · Physics 2015-06-05 M. Juvela , J. Malinen , T. Lunttila

The abundance of both amorphous and crystalline silicates in very small grains is limited by the fact that the 10 micron silicate emission feature is not detected in the diffuse ISM. On the basis of the observed IR emission spectrum for the…

Astrophysics · Physics 2009-10-31 Aigen Li , B. T. Draine

Semi-empirical molecular dynamics is used to simulate hydrocarbon grain sputtering and collisions which are extremely difficult to study experimentally. This microscopic and dynamic approach is particularly suited to high velocity impacts,…

Astrophysics · Physics 2009-11-10 Reanud Papoular

We show that space-based telescopes such as the proposed Terrestrial Planet Finder Coronagraph will be able to detect the light scattered by the interstellar grains along lines of sight passing near stars in our Galaxy. The relative flux of…

Astrophysics · Physics 2009-11-13 N. J. Turner , K. Grogan , J. B. Breckinridge

The present paper introduces a mathematical model for studying dynamic grain growth. In particular, we show how characteristic measurements, grain volumes, centroids, and central second-order moments at discrete moments in time can be…

Computational Physics · Physics 2023-05-31 Andreas Alpers , Maximilian Fiedler , Peter Gritzmann , Fabian Klemm

In many models of dusty objects in space the grains are assumed to be composite or fluffy. However, the computation of the optical properties of such particles is still a very difficult problem. We analyze how the increase of grain porosity…

Astrophysics · Physics 2009-11-11 N. V. Voshchinnikov , V. B. Il'in , Th. Henning , D. N. Dubkova

We characterize the force state of shear-loaded granular matter by relating the macroscopic stress to statistical properties of the force network. The purely repulsive nature of the interaction between grains naturally provides an upper…

Disordered Systems and Neural Networks · Physics 2007-05-23 Wouter G. Ellenbroek , Jacco H. Snoeijer

Recent interferometric surveys of nearby main-sequence stars show a faint but significant near-infrared excess in roughly two dozen systems, i.$\,$e. around $10\,\%$ to $30\,\%$ of stars surveyed. This excess is attributed to dust located…

Solar and Stellar Astrophysics · Physics 2017-02-01 Florian Kirchschlager , Sebastian Wolf , Alexander V. Krivov , Harald Mutschke , Robert Brunngräber

We describe experimental investigations of the structure of two-dimensional spherical crystals. The crystals, formed by beads self-assembled on water droplets in oil, serve as model systems for exploring very general theories about the…

The interstellar medium has a highly filamentary and hierarchical structure, which may play a significant role in star formation. A systematical study on the large-scale filaments towards their physical parameters, distribution, structures…

Astrophysics of Galaxies · Physics 2022-01-06 Yifei Ge , Ke Wang

Recent experimental results on the static or quasistatic response of granular materials have been interpreted to suggest the inapplicability of the traditional engineering approaches, which are based on elasto-plastic models (which are…

Soft Condensed Matter · Physics 2007-05-23 Chay Goldenberg , Isaac Goldhirsch

Grain alignment is a notoriously difficult problem, that is extremely rich in underlying physics. The long history of attempts theoretical handling of the problem resulted in rather sceptical approach to the theory on the part of some…

Astrophysics · Physics 2008-12-05 A. Lazarian

In this paper I review a series of observations which do not agree with the standard interpretation of the extinction curve. The consequence is that light we receive from a reddened star must be contaminated by starlight scattered at very…

Astrophysics · Physics 2009-11-07 Frederic Zagury