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Related papers: Particle characterization using THz spectroscopy

200 papers

Observations of interstellar extinction and polarization indicate that the interstellar medium consists of aligned non-spherical dust grains which show variation in the interstellar extinction curve for wavelengths ranging from NIR to UV.…

Astrophysics · Physics 2009-09-15 Ranjan Gupta , Tadashi Mukai , D. B. Vaidya , Asoke K. Sen , Yasuhiko Okada

A method is presented to infer simultaneously the wavelength-dependent real refractive index (RI) of the material of microspheres and their size distribution from extinction measurements of particle suspensions. To derive the averaged…

Optics · Physics 2018-05-23 Jonas Gienger , Markus Bär , Jörg Neukammer

This review focuses on numerical approaches to deducing the light-scattering and thermal-emission properties of primitive dust particles in planetary systems from astronomical observations. The particles are agglomerates of small grains…

Earth and Planetary Astrophysics · Physics 2016-03-14 Hiroshi Kimura , Ludmilla Kolokolova , Aigen Li , Jérémy Lebreton

This paper examines the variations, because of atmospheric extinction, of broad-band visible spectra, obtained from long-slit spectroscopy, in the vicinity of some stars, nebulae, and one faint galaxy.

Astrophysics · Physics 2015-06-24 Frederic Zagury

Extreme adaptive optics instruments have revealed exquisite details on debris discs, allowing to extract the optical properties of the dust particles such as the phase function, the degree of polarisation and the spectral reflectance. These…

We study the effect of variations in dust size distribution and composition on the correlation between the spectral shape of extinction (parameterized by $R_{\textrm{V}}$) and far-infrared dust emissivity (parameterized by the power-law…

Astrophysics of Galaxies · Physics 2021-05-20 Ioana A. Zelko , Douglas P. Finkbeiner

Speckle patterns observed in coherent optical imaging reflect important characteristic information of the scattering object. To capture speckle patterns, angular resolved or oblique illumination geometries are usually employed in…

Optics · Physics 2023-02-22 Kuangyi Xu , Zachery B. Harris , M. Hassan Arbab

Dust extinction curves provide one of the main avenues to understanding the detailed nature of dust grains and accounting for the effects of dust on observations of many astrophysical objects. For the first time, spectroscopic ultraviolet…

We consider a method for obtaining information on polarization of astronomical objects radiation at diffraction limited resolution - differential speckle polarimetry. As an observable we propose to use averaged cross spectrum of two…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Boris Safonov

We investigate the ability of high resolution X-ray spectroscopy to directly probe the grain composition of the interstellar medium. Using iron K-edge experimental data of likely ISM dust candidates taken at the National Synchrotron Light…

Astrophysics · Physics 2009-11-10 Julia C. Lee , Bruce Ravel

Dust polarization observations at optical wavelengths help to understand the dust grain properties and trace the plane-of-the-sky component of the magnetic field. In this study, we make use of the $I$-band polarization data acquired from…

Astrophysics of Galaxies · Physics 2022-08-09 N. Bijas , Chakali Eswaraiah , Jia-Wei Wang , Jessy Jose , Wen-Ping Chen , Di Li , Shih-Ping Lai , D. K. Ojha

The dust extinction curve is a critical component of many observational programs and an important diagnostic of the physics of the interstellar medium. Here we present new measurements of the dust extinction curve and its variation towards…

The spectral region around 10 micrometer, showing prominent dust emission bands, is commonly used to derive the chemical composition of protoplanetary dust. Different analysis methods have been proposed for this purpose, but so far, no…

Earth and Planetary Astrophysics · Physics 2014-11-18 Attila Juhasz , Thomas Henning , Jeroen Bouwman , Cornelis Dullemond , Ilaria Pascucci , Daniel Apai

The THz-TDS is a versatile technique and can be used to probe gas phase molecules. We are pushing the technique to its limit to try and detect trace gases at the sub-ppm levels. The experiments served as a reference for a quantitative…

Instrumentation and Detectors · Physics 2024-10-11 Noureddin Osseiran , Jeyan Bichon , Sophie Eliet , Romain Peretti

Debris disks give us the unique opportunity to probe the properties of small $\mu$m-sized particles, allowing us to peer into the constituents of their parent bodies, young analogs of comets and asteroids of our solar system. In the past,…

Earth and Planetary Astrophysics · Physics 2024-06-06 Johan Olofsson , Philippe Thébault , Amelia Bayo , Thomas Henning , Julien Milli

Multi-wavelength dust continuum observations of protoplanetary disks are essential for accurately measuring two key ingredients of planets formation theories: the dust mass and grain size. Unfortunately, they are also extremely…

Earth and Planetary Astrophysics · Physics 2025-01-24 Elena M. Viscardi , Enrique Macías , Francesco Zagaria , Anibal Sierra , Haochang Jiang , Tomohiro Yoshida , Pietro Curone

We extend and investigate the spheroidal model of interstellar dust grains used to simultaneously interpret the observed interstellar extinction and polarization curves. We compare our model with similar models recently suggested by other…

Astrophysics of Galaxies · Physics 2015-05-14 H. K. Das , N. V. Voshchinnikov , V. B. Il'in

A key to understand exoplanets is characterisation of their host stars. One of the most powerful tools to characterise stellar properties like effective temperature, surface gravity and metallicity, is spectroscopy based on observations of…

Earth and Planetary Astrophysics · Physics 2025-04-04 Carina M. Persson

Small angle scattering by dust grains causes a significant contribution to the total interstellar extinction for any X-ray instrument with sub-arcminute resolution (Chandra, Swift, XMM-Newton). However, the dust scattering component is not…

High Energy Astrophysical Phenomena · Physics 2016-02-24 L. Corrales , J. Garcia , J. Wilms , F. Baganoff

Recently, computational sampling methods have been implemented to spatially characterize terahertz (THz) fields. Previous methods usually rely on either specialized THz devices such as THz spatial light modulators, or complicated systems…

Optics · Physics 2019-06-19 Jiapeng Zhao , Yiwen E , Kaia Williams , Xi-cheng Zhang , Robert Boyd