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Related papers: On Buckyonions as an Interstellar Grain Component

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We used the Magellan adaptive optics system to image the 11 Myr substellar companion 1RXS 1609 B at the bluest wavelengths to date (z' and Ys). Comparison with synthetic spectra yields a higher temperature than previous studies of…

Recent space missions have provided information on the physical and chemical properties of interstellar grains such as the ratio $\beta$ of radiation pressure to gravity acting on the grains in addition to the composition, structure, and…

Astrophysics of Galaxies · Physics 2017-04-19 Hiroshi Kimura

Distance estimates derived from spectroscopy or parallax have been unified by considering extinction by large grains. The addition of such a population of what is called Dark Dust to models of the diffuse interstellar medium is tested…

Astrophysics of Galaxies · Physics 2023-02-22 Ralf Siebenmorgen

Recent results on nearby interstellar gas and interstellar byproducts within the solar system are used to select among the equilibrium radiative transfer models of the nearest interstellar material of Slavin and Frisch (2002). Assuming…

Astrophysics · Physics 2009-11-10 Priscilla C. Frisch Jonathan D. Slavin

We introduce a model for dust evolution in the RAMSES code for simulations of galaxies with a resolved multiphase interstellar medium. Dust is modelled as a fluid transported with the gas component, and is decomposed into two sizes, 5 nm…

The composition and properties of interstellar silicate dust are not well understood. In X-rays, interstellar dust can be studied in detail by making use of the fine structure features in the Si K-edge. The features in the Si K-edge offer a…

Astrophysics of Galaxies · Physics 2019-07-10 S. T. Zeegers , E. Costantini , D. Rogantini , C. P. de Vries , H. Mutschke , P. Mohr , F. de Groot , A. G. G. M. Tielens

We present a method to simultaneously infer the interstellar extinction parameters $A_0$ and $R_0$, stellar effective temperature $T_{\rm eff}$, and distance modulus $\mu$ in a Bayesian framework. Using multi-band photometry from SDSS and…

Astrophysics of Galaxies · Physics 2015-06-18 R. J. Hanson , C. A. L. Bailer-Jones

We investigate the distribution of the intrinsic extinction in NGC1569 using an extinction map derived from the H_alpha/H_beta emission line ratio. We compare the extinction distribution to that of the dust emission traced by SPITZER…

Astrophysics · Physics 2009-11-11 M. Relano , U. Lisenfeld , E. Battaner , J. M. Vilchez , P. Perez-Gonzalez

To trace the source of the unique 13, 19.5, and 28 $\mu$m emission features in the spectra of oxygen-rich circumstellar shells around AGB stars, we have compared dust extinction spectra obtained by aerosol measurements. We have measured the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 A. Tamanai , H. Mutschke , J. Blum , Th. Posch , C. Koike , J. W. Ferguson

We combine spectra of VY CMa obtained with the short- and long-wavelength spectrometers, SWS and LWS, on the Infrared Space Observatory to provide a first detailed continuum spectrum of this highly luminous star. The circumstellar dust…

The discoveries of huge amounts of dust and unusual extinction curves in high-redshift quasars (z > 4) cast challenging issues on the origin and properties of dust in the early universe. In this Letter, we investigate the evolutions of dust…

Astrophysics of Galaxies · Physics 2015-06-23 Takaya Nozawa , Ryosuke S. Asano , Hiroyuki Hirashita , Tsutomu T. Takeuchi

Our current understanding of the absorption and emission properties of interstellar grains are reviewed. The constraints placed by the Kramers-Kronig relation on the wavelength-dependence and the maximum allowable quantity of the dust…

Astrophysics · Physics 2009-11-10 Aigen Li

X-ray scattering is a powerful probe of the optical constants and grain size distribution of interstellar dust. Bright, transient sources are excellent tools for this, since they fade rapidly, leaving only the expanding scattered x-ray…

High Energy Astrophysical Phenomena · Physics 2025-09-03 Albert Sneppen , Darach Watson

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…

Astrophysics · Physics 2007-05-23 M. Landgraf , P. C. Frisch

The dust extinction towards bright HII regions in NGC 598 and NGC 5457 has been studied in detail by forming line ratios of Balmer and Paschen emission lines covering a large wavelength range. Three homogeneous models of the geometrical…

Astrophysics · Physics 2007-05-23 Lars Petersen , Peter Gammelgaard

In order to study the effect of dust extinction on the afterglow of gamma-ray bursts (GRBs), we carry out numerical calculations with high precision based on rigorous Mie theory and latest optical properties of interstellar dust grains, and…

High Energy Astrophysical Phenomena · Physics 2011-08-26 Gu-Jing Lv , Lang Shao , Zhi-Ping Jin , Da-Ming Wei

Observationally, both the 3.4micron aliphatic hydrocarbon C--H stretching absorption feature and the 9.7micron amorphous silicate Si--O stretching absorption feature show considerable variations from the local diffuse interstellar medium…

Astrophysics · Physics 2014-11-18 Jian Gao , B. W. Jiang , Aigen Li

A full spectral characterization of carbonaceous dust analogs is necessary to understand their potential as carriers of observed astronomical spectral signatures such as the ubiquitous UV bump at 217.5 nm and the far-ultraviolet (FUV) rise…

Instrumentation and Methods for Astrophysics · Physics 2016-02-01 L. Gavilan , I. Alata , K. C. Le , T. Pino , A. Giuliani , E. Dartois

Using a sample of gamma-ray burst (GRB) afterglows detected by both the X-Ray and the UV/Optical Telescopes (XRT and UVOT) on Swift, we modelled the spectral energy distributions (SEDs) to determine gas column densities and dust extinction…

It is generally agreed that interstellar dust grains consist of two main components, namely, silicates and graphites. Some models, like MRN model, assume these grains to be homogeneous spheres following a power law size distribution. This…

Astrophysics of Galaxies · Physics 2009-03-30 Ashim K. Roy , Subodh K. Sharma , Ranjan Gupta
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