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相关论文: Variation in dust properties in a dense filament o…

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Dust emission is an important tool in studies of star-forming clouds, as a tracer of column density and indirectly via the dust evolution that is connected to the history and physical conditions of the clouds. We examine radiative transfer…

星系天体物理 · 物理学 2024-01-24 M. Juvela

We present Spitzer images of the Taurus Complex (TC) and take advantage of the sensitivity and spatial resolution of the observations to characterize the diffuse IR emission across the cloud. This work highlights evidence of dust evolution…

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…

The far-infrared (FIR) opacity of dust in dark clouds within the Ophiuchus molecular cloud is investigated through multi-wavelength infrared observations from UKIDSS, Spitzer and Herschel. Employing the infrared color excess technique with…

星系天体物理 · 物理学 2024-02-19 Jun Li , Biwei Jiang , He Zhao , Xi Chen , Yang Yang

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

Context: The study of dust emission at millimeter wavelengths is important to shed light on the dust properties and physical structure of pre-stellar cores, the initial conditions in the process of star and planet formation. Aims: Using two…

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…

天体物理学 · 物理学 2009-11-11 N. V. Voshchinnikov , V. B. Il'in , Th. Henning , D. N. Dubkova

Dust in the diffuse interstellar medium remains incompletely understood with regard to the structure, composition, size distribution, and alignment properties of the grains. Joint observations of reddening, starlight polarisation spectra,…

星系天体物理 · 物理学 2026-05-27 Ralf Siebenmorgen , Stefano Bagnulo , Lapo Fanciullo , Thomas Vannieuwenhuyse , Vincent Guillet

We study infrared emission of 17 isolated, diffuse clouds with masses of order solar masses, to test the hypothesis that grain property variations cause the apparently low gas-to-dust ratios that have been measured in those clouds. Maps of…

星系天体物理 · 物理学 2018-08-13 William T. Reach , Jean-Philippe Bernard , Thomas Jarrett , Carl Heiles

We have studied the opacity of dust grains at submillimeter wavelengths by estimating the optical depth from imaging at 160, 250, 350, and 500 um from the Herschel Gould Belt Survey and comparing this to a column density obtained from the…

Maps of estimated dust column density in molecular clouds are usually assumed to reliably trace the total gas column density structure. In this work we present results showing a clear discrepancy between the dust and the gas distribution in…

We have analyzed the properties of dust in the high galactic latitude translucent cloud Lynds 1780 using ISOPHOT maps at 100 and 200 micrometers and raster scans at 60, 80, 100, 120, 150 and 200 micrometers. In far-infrared (FIR) emission,…

天体物理学 · 物理学 2009-11-11 M. Ridderstad , M. Juvela , K. Lehtinen , D. Lemke , T. Liljestrom

We study the extinction properties of the composite dust grains, consisting of host silicate spheroids and graphite as inclusions, using discrete dipole approximation (DDA). We calculate the extinction cross sections of the composite grains…

太阳与恒星天体物理 · 物理学 2015-06-17 Nisha Katyal , Ranjan Gupta , D B Vaidya

We model the ALMA and VLA millimeter radial profiles of the disk around HL Tau to constrain the properties of the dust grains. We adopt the disk evolutionary models of Lynden-Bell \& Pringle and calculate their temperature and density…

太阳与恒星天体物理 · 物理学 2020-01-08 Carlos Tapia , Susana Lizano , Anibal Sierra , Carlos Carrasco-González , Elly Bayona-Bobadilla

Planet formation around young stars requires the growth of interstellar dust grains from mm-sized particles to km-sized planetesimals. Numerical simulations have shown that large ($\sim$mm-sized) grains found in the inner envelope of young…

Variations in the observed dust emission and extinction indicate a systematic evolution of grain properties in the transition from the diffuse interstellar medium (ISM) to denser molecular clouds. The differences in the dust spectral energy…

星系天体物理 · 物理学 2015-06-05 Melanie Köhler , Nathalie Ysard , Anthony P. Jones

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…

星系天体物理 · 物理学 2018-10-03 N. Ysard , A. P. Jones , K. Demyk , T. Boutéraon , M. Koehler

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…

天体物理学 · 物理学 2009-10-19 L. Cambresy , T. H. Jarrett , C. A. Beichman

With Planck and Herschel, we now have the spectral coverage and angular resolution required to observe dense and cold molecular clouds. As these clouds are optically thick at short wavelength but optically thin at long wavelength, it is…

The Planck-HFI all-sky survey from 353 to 857GHz combined with the 100 microns IRAS show that the dust properties vary in the diffuse ISM at high Galactic latitude (1e19<NH<2.5e20 H/cm2). Our aim is to explain these variations with changes…

星系天体物理 · 物理学 2015-05-13 N. Ysard , M. Koehler , A. Jones , M. -A. Miville-Deschênes , A. Abergel , L. Fanciullo
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