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Interstellar polarization at far-infrared through millimeter wavelengths (0.1 - 1 mm) is primarily due to thermal emission from dust grains aligned with magnetic fields. This mechanism has led to studies of magnetic fields in a variety of…

Astrophysics of Galaxies · Physics 2009-04-14 John E. Vaillancourt

Dust coagulation in protoplanetary disks is not straightforward and is subject to several slow-down mechanisms, such as bouncing, fragmentation and radial drift to the star. Furthermore, dust grains in UV-shielded disk regions are…

Solar and Stellar Astrophysics · Physics 2023-08-09 Vitaly Akimkin , Alexei V. Ivlev , Paola Caselli , Munan Gong , Kedron Silsbee

Turbulent coagulation in protoplanetary disks is known to operate on timescale far shorter than the lifetime of the disk. In the absence of mechanisms that replenish the small dust grain population, protoplanetary disks would rapidly lose…

Astrophysics · Physics 2009-11-13 C. Dominik , C. P. Dullemond

Recent photometry of L and T dwarfs revealed that the infrared colors show a large variation at a given Teff and, within the framework of our Unified Cloudy Model (UCM), this result can be interpreted as due to a variation of the critical…

Astrophysics · Physics 2009-11-10 Takashi Tsuji

Planets have been detected around a variety of stars, including low-mass objects, such as brown dwarfs. However, such extreme cases are challenging for planet formation models. Recent sub-millimeter observations of disks around brown dwarf…

Earth and Planetary Astrophysics · Physics 2013-05-20 P. Pinilla , T. Birnstiel , M. Benisty , L. Ricci , A. Natta , C. P. Dullemond , C. Dominik , L. Testi

Since in situ studies and interplanetary dust collections only provide a spatially limited amount of information about the interplanetary dust properties, it is of major importance to complete these studies with properties inferred from…

Earth and Planetary Astrophysics · Physics 2016-09-20 Jeremie Lasue , Anny-Chantal Levasseur-Regourd , Nicolas Fray , Hervé Cottin

We have calculated the radiation field, dust grain temperatures, and far infrared emissivity of numerical models of turbulent molecular clouds. When compared to a uniform cloud of the same mean optical depth, most of the volume inside the…

Astrophysics · Physics 2009-11-10 Thomas Bethell , Ellen Zweibel , Fabian Heitsch , J. S. Mathis

The degree of porosity in interstellar dust-grain material is poorly defined, although recent work has suggested that the grains could be highly porous. Aside from influencing the optical properties of the dust, porosity has the potential…

Astrophysics of Galaxies · Physics 2021-04-28 Drew A. Christianson , Robin T. Garrod

We present an analysis of the dust optical properties at large scale, for the whole galactic anticenter hemisphere. We used the 2MASS Extended Source Catalog to obtain the total reddening on each galaxy line of sight and we compared this…

Astrophysics · Physics 2009-10-19 L. Cambresy , T. H. Jarrett , C. A. Beichman

We investigate the evolution of interfaces among phases of the interstellar medium with different temperature. It is found that, for some initial conditions, the dynamical effects related to conductive fronts are very important even if…

Astrophysics · Physics 2009-10-22 Andrea Ferrara , Yuri Shchekinov

Dust and associated depletion of heavy elements from the gas phase can modify the thermal properties of HII regions from the dust-free case, with significant consequences for the emergent optical spectrum. We present the results of…

Astrophysics · Physics 2009-10-28 Joseph C. Shields , Robert C. Kennicutt

A key parameter governing the secular evolution of protoplanetary disks is their outer radius. In this paper, the feedback of realistic dust grain size distributions onto the gas emission is investigated. Models predict that the difference…

Solar and Stellar Astrophysics · Physics 2018-09-12 Stefano Facchini

The radiative cooling of optically thin gaseous regions and the formation of a two-phase medium and of cold gas clouds with a clumpy substructure is investigated. In optically thin clouds, the growth rate of small isobaric density…

Astrophysics · Physics 2009-10-31 A. Burkert , D. N. C. Lin

Context. Dust is a fundamental component of the interstellar medium (ISM) and plays a critical role in galaxy evolution. Dust grains influence the ISM by cooling the gas, altering its chemistry, and absorbing stellar radiation, re-emitting…

In a molecular cloud dust opacity typically dominates over gas opacity, yet in the vicinities of forming stars dust is depleted, and gas is the sole provider of opacity. In the optically thin circumstellar environments the radiation…

Solar and Stellar Astrophysics · Physics 2014-09-05 M. G. Malygin , R. Kuiper , H. Klahr , C. P. Dullemond , Th. Henning

In protoplanetary disks, the formation of planetesimals via streaming and/or gravitational instabilities requires regions with a locally enhanced dust-to-gas mass ratio. Conventionally, gas pressure maxima sustained by gas surface density…

Earth and Planetary Astrophysics · Physics 2025-04-15 Ryo Kato , Takahiro Ueda , Satoshi Okuzumi

(abridged) In the core accretion scenario for the formation of planetary rocky cores, the first step toward planet formation is the growth of dust grains into larger and larger aggregates and eventually planetesimals. Although dust grains…

Transitional discs have central regions characterised by significant depletion of both dust and gas compared to younger, optically-thick discs. However, gas and dust are not depleted by equal amounts: gas surface densities are typically…

Solar and Stellar Astrophysics · Physics 2020-09-02 Mark R. Krumholz , Michael J. Ireland , Kaitlin M. Kratter

The $\mathrm{H}_2$ formation on grains is known to be sensitive to dust temperature, which is also known to fluctuate for small grain sizes due to photon absorption. We aim at exploring the consequences of simultaneous fluctuations of the…

Astrophysics of Galaxies · Physics 2014-10-01 Emeric Bron , Jacques Le Bourlot , Franck Le Petit

The inner regions of protoplanetary disks are host to the sublimation of dust grains, a process traditionally modeled using equilibrium thermodynamics. We demonstrate through ab-initio density functional theory (DFT) and kinetic Monte Carlo…

Earth and Planetary Astrophysics · Physics 2025-09-16 Sheng Xu , Lile Wang , Luis C. Ho , Renyue Cen , Shenzhen Xu