English
Related papers

Related papers: An Atmospheric Structure Equation for Grain Growth

200 papers

We calculate the physical structure of protoplanetary disks by evaluating the gas density and temperature self-consistently and solving separately for the dust temperature. The effect of grain growth is taken into account by assuming a…

Astrophysics · Physics 2009-11-11 Yuri Aikawa , Hideko Nomura

The properties of interstellar grains, such as grain size distribution and grain porosity, are affected by interstellar processing, in particular, coagulation and shattering, which take place in the dense and diffuse interstellar medium…

Astrophysics of Galaxies · Physics 2021-01-13 Hiroyuki Hirashita , Vladimir B. Il'in , Laurent Pagani , Charlène Lefèvre

Recent observations indicate that mm/cm-sized grains may exist in the embedded protostellar disks. How such large grains grow from the micron size (or less) in the earliest phase of star formation remains relatively unexplored. In this…

Earth and Planetary Astrophysics · Physics 2022-07-29 Yisheng Tu , Zhi-Yun Li , Ka Ho Lam

We developed a grain growth model that is based on the energy minimisation of surfaces with respect to the volume energy and the grain's environment. We used the well-known FePt L1$_\text{0}$ system to discover the physical factors that…

Materials Science · Physics 2022-09-14 Connor Skelland , Gino Hrkac

In order to explain grain growth to mm sized particles and their retention in outer regions of protoplanetary disks, as it is observed at sub-mm and mm wavelengths, we investigate if strong inhomogeneities in the gas density profiles can…

Earth and Planetary Astrophysics · Physics 2012-02-14 P. Pinilla , T. Birnstiel , L. Ricci , C. P. Dullemond , A. L. Uribe , L. Testi , A. Natta

Grain size is an important control on mantle viscosity and permeability, but is difficult or impossible to measure in situ. We construct a two-dimensional, single phase model for the steady-state mean grain size beneath a mid-ocean ridge.…

Geophysics · Physics 2015-06-23 Andrew J. Turner , Richard F. Katz , Mark D. Behn

Context. Grains in circumstellar disks are believed to grow by mutual collisions and subsequent sticking due to surface forces. Results of many fields of research involving circumstellar disks, such as radiative transfer calculations, disk…

Earth and Planetary Astrophysics · Physics 2010-09-20 T. Birnstiel , C. W. Ormel , C. P. Dullemond

Dust coagulation in interstellar space and protoplanetary disks is usually treated as one of 2 extreme cases: Particle-Cluster Aggregation and Cluster-Cluster Aggregation. In this paper we study the process of hierarchical growth, where…

Earth and Planetary Astrophysics · Physics 2016-11-02 Carsten Dominik , Dominik Paszun , Herman Borel

Grains are determinant for setting the chemical, physical, dynamical, and radiative properties of all the media in which they are present. Their influence depends on the grain composition, size, and geometrical structure which vary…

Astrophysics of Galaxies · Physics 2018-10-03 N. Ysard , A. P. Jones , K. Demyk , T. Boutéraon , M. Koehler

A formula of grain growth rate, based on a nonlinear capillarity-driven relation, is derived to predict and interpret realistic growth processes in polycrystalline systems. The derived formula reveals how the growth and stagnation of grains…

Materials Science · Physics 2017-12-12 Jianfeng Hu , Xianhao Wang

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

The first challenge in the formation of both terrestrial planets and the cores of gas giants is the retention of grains in protoplanetary disks. In most regions of these disks, gas attains sub-Keplerian speeds as a consequence of a negative…

Astrophysics · Physics 2009-11-13 Katherine A. Kretke , D. N. C. Lin

Grain growth by the accretion of metals in interstellar clouds (called `grain growth') could be one of the dominant processes that determine the dust content in galaxies. The importance of grain size distribution for the grain growth is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Hiroyuki Hirashita , Tzu-Ming Kuo

[Abridged] In this paper we explore grain size effects on wind properties of carbon stars, using a generalized description of radiative cross sections valid for particles of arbitrary sizes. The purpose of the study is to investigate under…

Solar and Stellar Astrophysics · Physics 2015-05-28 Lars Mattsson , Susanne Höfner

There are indications that interstellar and interplanetary dust grains have an inhomogeneous and fluffy structure. We investigate different methods to describe light scattering by such composite particles. Both a model of layered particles…

Astrophysics · Physics 2009-11-10 N. V. Voshchinnikov , V. B. Il'in , Th. Henning

Giant protoplanets formed by gravitational instability in the outer regions of circumstellar disks go through an early phase of quasi-static contraction during which radii are large and internal temperatures are low. The main source of…

Earth and Planetary Astrophysics · Physics 2015-05-19 Ravit Helled , Peter Bodenheimer

We present a calculation of the sedimentation of grains in a giant gaseous protoplanet such as that resulting from a disk instability of the type envisioned by Boss (1998). Boss (1998) has suggested that such protoplanets would form cores…

Astrophysics · Physics 2009-11-13 Ravit Helled , Morris Podolak , Attay Kovetz

Grain growth experiments on thin metallic films have shown the geometric and topological characteristics of the grain structure to be universal and independent of many experimental conditions. The universal size distribution, however, is…

Materials Science · Physics 2017-11-21 Rainer Backofen , Katayun Barmak , Ken Elder , Axel Voigt

Dust grains play a crucial role in the modeling of protostellar formation, particularly through their opacity and interaction with the magnetic field. The destruction of dust grains in numerical simulations is currently modeled primarily by…

Astrophysics of Galaxies · Physics 2025-02-05 Antonin Borderies , Benoît Commerçon , Bernard Bourdon

We study the impact of dust evolution in a protoplanetary disk around a T Tauri star on the disk chemical composition. For the first time we utilize a comprehensive model of dust evolution which includes growth, fragmentation and…

Astrophysics of Galaxies · Physics 2015-05-20 A. I. Vasyunin , D. S. Wiebe , T. Birnstiel , S. Zhukovska , Th. Henning , C. P. Dullemond