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相关论文: The Ubiquity of Micrometer-Sized Dust Grains in th…

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We investigate the condition for the formation of micron-sized grains in dense cores of molecular clouds. This is motivated by the detection of the mid-infrared emission from deep inside a number of dense cores, the so-called `coreshine,'…

星系天体物理 · 物理学 2015-06-16 Hiroyuki Hirashita , Zhi-Yun Li

Context. Using observations to deduce dust properties, grain size distribution, and physical conditions in molecular clouds is a highly degenerate problem. Aims. The coreshine phenomenon, a scattering process at 3.6 and 4.5 $\mu$m that…

Interstellar dust spans a wide range in size distribution, ranging from ultrasmall grains of a few Angstroms to micrometer-size grains. While the presence of nanometer-size dust grains in the Galactic interstellar medium was speculated six…

星系天体物理 · 物理学 2018-11-14 Yanxia Xie , Luis C. Ho , Aigen Li , Jinyi Shangguan

Planet formation in protoplanetary discs requires dust grains to coagulate from the sub-micron sizes that are found in the interstellar medium into much larger objects. For the first time, we study the growth of dust grains during the…

星系天体物理 · 物理学 2022-06-01 Matthew R. Bate

Computational models of interstellar gas-grain chemistry have historically adopted a single dust-grain size of 0.1 micron, assumed to be representative of the size distribution present in the interstellar medium. Here, we investigate the…

星系天体物理 · 物理学 2016-02-03 Tyler Pauly , Robin T. Garrod

We argue that impact velocities between dust grains with sizes less than $\sim 0.1$ $\mu m$ in molecular cloud cores are dominated by drift arising from ambipolar diffusion. This effect is due to the size dependence of the dust coupling to…

星系天体物理 · 物理学 2020-09-30 Kedron Silsbee , Alexei Ivlev , Paola Caselli , Olli Sipila , Bo Zhao

Our current understanding of interstellar dust is summarized at an introductory level. Submicron-sized interstellar dust grains absorb and scatter light, and reradiate the absorbed energy in the infrared. The grain population spans a range…

天体物理学 · 物理学 2009-10-31 B. T. Draine

In the interstellar medium of the Milky Way, certain elements -- e.g., Mg, Si, Al, Ca, Ti, Fe -- reside predominantly in interstellar dust grains. These grains absorb, scatter, and emit electromagnetic radiation, heat the interstellar…

天体物理学 · 物理学 2007-05-23 B. T. Draine

We review the properties of dust in protoplanetary disks around optically visible pre-main sequence stars obtained with a variety of observational techniques, from measurements of scattered light at visual and infrared wavelengths to…

天体物理学 · 物理学 2007-05-23 A. Natta , L. Testi , N. Calvet , Th. Henning , R. Waters , D. Wilner

We present a model of the interaction of interstellar dust grains with a stellar environment, that predicts the distribution of interstellar dust grains in the size range between $0.1 {\rm \mu m}$ and $1 {\rm \mu m}$ around a star for the…

天体物理学 · 物理学 2007-05-23 M. Landgraf , P. C. Frisch

A big question in the field of star and planet formation is the time at which substantial dust grain growth occurs. The observed properties of dust emission across different wavelength ranges have been used as an indication that…

星系天体物理 · 物理学 2022-12-14 Kedron Silsbee , Vitaly Akimkin , Alexei V. Ivlev , Leonardo Testi , Munan Gong , Paola Caselli

There is a long-standing discussion in the astrophysical/astrochemical community as to the structure and morphology of dust grains in various astrophysical environments (e.g., interstellar clouds, protostellar envelopes, protoplanetary and…

We are living in a dusty universe: dust is ubiquitously seen in a wide variety of astrophysical environments, ranging from circumstellar envelopes around cool red giants to supernova ejecta, from diffuse and dense interstellar clouds and…

天体物理学 · 物理学 2007-05-23 Aigen Li

Grain growth during star formation affects the physical and chemical processes in the evolution of star-forming clouds. We investigate the origin of the millimeter (mm)-sized grains recently observed in Class I protostellar envelopes. We…

太阳与恒星天体物理 · 物理学 2016-06-14 Yi Hang Valerie Wong , Hiroyuki Hirashita , Zhi-Yun Li

Models of astrophysical dust are key to understand several physical processes, from the role of dust grains as cooling agents in the ISM to their evolution in dense circumstellar disks, explaining the occurrence of planetary systems around…

星系天体物理 · 物理学 2025-06-18 M. -A. Carpine , N. Ysard , A. Maury , A. Jones

(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…

Interstellar dust is a major foreground contaminant for many observations and a key component in the chemistry of the interstellar medium, yet its properties remain highly uncertain. Using low-resolution spectra, we accurately measure the…

星系天体物理 · 物理学 2024-07-23 Xiangyu Zhang , Gregory Green

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…

星系天体物理 · 物理学 2016-06-24 Lars Mattsson

Dust grains coagulate into larger aggregates in dense gas. This changes their size distribution and possibly affects the thermal evolution of star-forming clouds. We here investigate dust coagulation in collapsing pre-stellar cores with…

星系天体物理 · 物理学 2015-05-13 Hiroyuki Hirashita , Kazuyuki Omukai

The dust in the interstellar medium, that provides the material for forming stars - and circumstellar discs as a natural by-product - is known to have submicron sizes. As these discs are the sites of planet formation, those small grains are…

太阳与恒星天体物理 · 物理学 2009-03-04 Gwendolyn Meeus
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