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Related papers: Opacity of fluffy dust aggregates

200 papers

We observed the L1506 filament, which is located in the Taurus molecular complex, with the Herschel PACS and SPIRE instruments. Our aim is to prove the variation in grain properties along the entire length of the filament. In particular, we…

We perform light-scattering numerical simulations for two dust populations: (i) consolidated porous particles computed with the discrete dipole approximation (ADDA) and (ii) highly porous aggregate models, including fractal and hierarchical…

The Rosseland mean opacity of dust in protoplanetary disks is often calculated assuming the interstellar medium (ISM) size distribution and a constant dust-to-gas ratio. However, the dust size distribution and the dust-to-gas ratio in…

Earth and Planetary Astrophysics · Physics 2021-09-28 Yayaati Chachan , Eve J. Lee , Heather A. Knutson

To study the evolution of protoplanetary dust aggregates, we performed experiments with up to 2600 collisions between single, highly-porous dust aggregates and a solid plate. The dust aggregates consisted of spherical SiO$_2$ grains with…

Earth and Planetary Astrophysics · Physics 2011-02-11 René Weidling , Carsten Güttler , Jürgen Blum , Frithjof Brauer

We present the first spatially resolved mid-infrared (37.1 $\mu$m) image of the Fomalhaut debris disk. We use PSF fitting and subtraction to distinctly measure the flux from the unresolved component and the debris disk. We measure an…

Earth and Planetary Astrophysics · Physics 2018-08-08 J. D. Adams , T. L. Herter , R. M. Lau , C. Trinh , M. Hankins

We present a model for the diffuse interstellar dust that explains the observed wavelength-dependence of extinction, emission, linear and circular polarisation of light. The model is set-up with a small number of parameters. It consists of…

Astrophysics of Galaxies · Physics 2015-06-16 R. Siebenmorgen , N. V. Voshchinnikov , S. Bagnulo

Combining a particle-particle, particle-cluster and cluster-cluster agglomeration model with an aggregate charging model, the coagulation and charging of dust particles in various plasma environments relevant for proto-planetary disks have…

Plasma Physics · Physics 2015-05-28 L. S. Matthews , V. Land , T. W. Hyde

Polarization at millimeter wavelengths provides a powerful diagnostic of dust grain properties in protoplanetary disks. Standard models based on solid spherical grains often struggle to reproduce the observed polarization fractions and…

Dust growth from micron- to planet-size in protoplanetary discs involves multiple physical processes, including dust collisions, the streaming instability, and pebble accretion. Disc turbulence and dust fragility matter at almost every…

Earth and Planetary Astrophysics · Physics 2026-01-14 Simin Tong , Richard Alexander , Giovanni Rosotti

A correlation between proto-planetary disc radii and sub-mm fluxes has been recently reported. In this Letter we show that the correlation is a sensitive probe of grain growth processes. Using models of grain growth and drift, we have shown…

Earth and Planetary Astrophysics · Physics 2019-05-08 Giovanni P. Rosotti , Richard A. Booth , Marco Tazzari , Cathie Clarke , Giuseppe Lodato , Leonardo Testi

Dust determines the temperature structure of protoplanetary disks. However, dust temperature determinations almost invariably rely on a complex modeling of the Spectral Energy Distribution. We attempt a direct determination of the…

Solar and Stellar Astrophysics · Physics 2016-01-27 S. Guilloteau , V. Piétu , E. Chapillon , E. Di Folco , A. Dutrey , T. Henning , D. Semenov , T. Birnstiel , N. Grosso

A pathway to the formation of planetesimals, and eventually giant planets, may occur in concentrations of dust grains trapped in pressure maxima. Dramatic crescent-shaped dust concentrations have been seen in recent radio images at sub-mm…

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

For the investigation of collisions among protoplanetesimal dust aggregates, we performed microgravity experiments in which the impacts of high-porosity mm-sized dust aggregates into 2.5 cm-sized high-porosity dust aggregates can be…

Astrophysics · Physics 2009-11-13 Doreen Langkowski , Jens Teiser , Jürgen Blum

We explore whether assumptions about dust grain shape affect resulting estimates of the composition and grain size distribution of the AU Microscopii (AU Mic) debris disk from scattered light data collected by Lomax et al. (2018). The near…

Earth and Planetary Astrophysics · Physics 2022-06-01 Jessica A. Arnold , Alycia J. Weinberger , Gorden Videen , Evgenij S. Zubko

We present Monte Carlo radiative transfer simulations for spiral galaxies modelled as a stellar disk and a two-phase clumpy dust distribution. We divide the volume occupied by the dust into a three-dimensional grid and assign each cell a…

Astrophysics · Physics 2009-10-31 Simone Bianchi , Andrea Ferrara , Jon Davies , Paul Alton

To characterize the mechanisms of planet formation it is crucial to investigate the properties and evolution of protoplanetary disks around young stars, where the initial conditions for the growth of planets are set. Our goal is to study…

When modeling the density and grain size distribution in debris disks, the minimum particle size is often significantly larger than the corresponding blowout size. While the dust particles are usually modeled as compact, homogenous spheres,…

Solar and Stellar Astrophysics · Physics 2013-02-22 Florian Kirchschlager , Sebastian Wolf

We introduce a possible disruption mechanism of dust grains in planet formation by their spinning motion. This mechanism has been discussed as rotational disruption for the interstellar dust grains. We theoretically calculate whether porous…

Earth and Planetary Astrophysics · Physics 2021-06-09 Misako Tatsuuma , Akimasa Kataoka

Determination of the composition and size distribution of dust grains in debris discs is strongly dependent on constraining the underlying spatial distribution of that dust through multi-wavelength, spatially resolved imaging spanning…

Earth and Planetary Astrophysics · Physics 2025-12-16 J. P. Marshall , S. Hengst , R. Young , F. Kemper , L. Matrà , N. Pawellek , H. Kobayashi , P. Scicluna , S. T. Zeegers