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Related papers: Particle characterization using THz spectroscopy

200 papers

We analyze low resolution Spitzer infrared (IR) 5-14 micron spectra of the diffuse emission toward a carefully selected sample of stars. The sample is composed of sight lines toward stars that have well determined ultraviolet (UV)…

Astrophysics of Galaxies · Physics 2022-02-02 Derck Massa , Karl D. Gordon , E. L. Fitzpatrick

Spectropolarimetry from the near IR to the far UV of light scattered by dust provides a valuable diagnostic of the dust composition, grain size distribution and spatial distribution. To facilitate the use of this diagnostic, we present…

Astrophysics · Physics 2009-10-31 Victor G. Zubko , Ari Laor

The large majority of extinction sight lines in our Galaxy obey a simple relation depending on one parameter, the total-to-selective extinction coefficient, Rv. Different values of Rv are able to match the whole extinction curve through…

Astrophysics of Galaxies · Physics 2015-05-20 Paola Mazzei , Guido Barbaro

Multi-wavelength spectroscopy can be used to constrain the dust and gas properties in debris disks. Circumstellar dust absorbs and scatters incident stellar light. The scattered light is sometimes resolved spatially at visual and…

Earth and Planetary Astrophysics · Physics 2015-05-13 Christine H. Chen

The effects of dust extinction on the departure from axi-symmetry in the morphology of planetary nebulae (PNs) are investigated through a comparison of the radio free-free emission and hydrogen recombination line images. The dust…

Astrophysics · Physics 2009-11-13 T. -H. Lee , S. Kwok

We describe a THz spectrometer operating between 1.2 and 10.5 THz, consisting of band pass filters made with metasurfaces. The source is made of 10 W small black body. The detector is a high sensitivity room temperature pyroelectric sensor.…

Instrumentation and Detectors · Physics 2020-05-22 F. Martini , E. Giovine , F. Chiarello , P. Carelli

Dust extinction is the most robust tracer of the gas distribution in the interstellar medium, but measuring extinction is limited by the systematic uncertainties involved in estimating the intrinsic colors to background stars. In this paper…

Instrumentation and Methods for Astrophysics · Physics 2017-05-24 Stefan Meingast , Marco Lombardi , Joao Alves

THz time domain spectroscopy is a powerful technique enabling the investigation of different materials in the far-infrared frequency range. Even if nowadays this technique is well established, its application to very thin films remains…

Instrumentation and Detectors · Physics 2024-06-07 A. Taschin , P. Bartolini , J. Tasseva , R. Torre

THz spectroscopy has reached imaging capability with a spatial resolution of a few micrometres. This property enables measurements and imaging of biological samples like cells. THz photons have very low photon energies in the…

Interstellar dust extinction curves provide valuable information about dust properties, including the composition and size of the dust grains, and are essential to correct observations for the effects of interstellar dust. In this work, we…

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

A general theoretical framework is developed for interpreting spectropolarimetric observations of optically thin emission line scattering from small dust particles. Spatially integrated and spatially resolved line profiles of both scattered…

Astrophysics · Physics 2009-10-22 W. J. Henney

A novel THz near-field spectrometer is presented which allows to perform biological and medical studies with high spectral resolution combined with a spatial resolution down to l/100. In the setup an aperture much smaller than the used…

Biological Physics · Physics 2009-11-07 S. Mair , B. Gompf , M. Dressel

The dust extinction curve is typically parameterized by a single variable, R(V), in optical and near-infrared wavelengths. R(V) controls the slope of the extinction-vs.-wavelength curve, and is thought to reflect the grain-size distribution…

Astrophysics of Galaxies · Physics 2025-06-26 Gregory M. Green , Xiangyu Zhang , Ruoyi Zhang

The distance to the stars is a fundamental parameter, which is determined via two primary methods - parallax and luminosity. While the parallax is a direct trigonometric method, the luminosity distance is usually influenced by interstellar…

Astrophysics of Galaxies · Physics 2024-12-30 Ralf Siebenmorgen , Frank Heymann , Rolf Chini

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,…

Astrophysics of Galaxies · Physics 2026-05-27 Ralf Siebenmorgen , Stefano Bagnulo , Lapo Fanciullo , Thomas Vannieuwenhuyse , Vincent Guillet

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

THz near field microscopy opens a new frontier in material science. High spatial resolution requires the detection crystal to have uniform and reproducible response. We present the THz near field spatial and temporal response of ZnTe and…

Materials Science · Physics 2015-07-24 Katherine A. Niessen , A. G. Markelz

We present a new technique for determining the *quantity and composition* of dust in astrophysical environments using <6keV X-rays. We argue that high resolution X-ray spectra as enabled by the Chandra and XMM-Newton gratings should be…

Instrumentation and Methods for Astrophysics · Physics 2009-08-24 Julia C. Lee , Jingen Xiang , Bruce Ravel , Jeffrey Kortright , Kathryn Flanagan

Interstellar dust plays a central role in shaping the detailed structure of the interstellar medium, thus strongly influencing star formation and galaxy evolution. Dust extinction provides one of the main pillars of our understanding of…

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