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Related papers: Sensitivity of Polarization to Grain Shape: II. Ag…

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We study the effects of using the optical properties of irregular hexahedral grains in photoionization models of circumstellar nebulae around evolved stars. Dust opacities for the irregular grains were obtained from the scattering…

Astrophysics of Galaxies · Physics 2026-04-13 P. Jiménez-Hernández , S. J. Arthur , D. Guirado , O. Muñoz , J. Martikainen , L. Sabin , W. J. Henney

The polarisation of light induced by aligned interstellar dust serves as a significant tool in investigating cosmic magnetic fields, dust properties, and poses a challenge in characterising the polarisation of the cosmic microwave…

We have used the Hubble Space Telescope/ACS coronagraph to make polarization maps of the AU Mic debris disk. The fractional linear polarization rises monotonically from about 0.05 to 0.4 between 20 and 80 AU. The polarization is…

Astrophysics · Physics 2011-02-11 James R. Graham , Paul G. Kalas , Brenda C. Matthews

Magnetic fields permeate the entire Galaxy and are essential to, for example, the regulation of several stages of the star formation process and cosmic ray transportation. Unraveling its properties, such as intensity and topology, is an…

Polarized continuum emission from aligned grains in disks around young stellar objects can be used to probe the magnetic field, radiation anisotropy, or drift between dust and gas, depending on whether the non-spherical grains are aligned…

Solar and Stellar Astrophysics · Physics 2020-04-09 Zhe-Yu Daniel Lin , Zhi-Yun Li , Haifeng Yang , Leslie Looney , Chin-Fei Lee , Ian Stephens , Shih-Ping Lai

The dielectric function of interstellar dust material is modeled using observations of extinction and polarization in the infrared, together with estimates for the mass of interstellar dust. The "astrodust" material is assumed to be a mix…

Astrophysics of Galaxies · Physics 2021-03-17 B. T. Draine , Brandon S. Hensley

We present a new method to constrain the grain size in protoplanetary disks with polarization observations at millimeter wavelengths. If dust grains are grown to the size comparable to the wavelengths, the dust grains are expected to have a…

Multiwavelength dust continuum and polarization observations arising from self-scattering have been used to investigate grain sizes in young disks. However, the polarization by self-scattering is low in face-on optically thick disks and…

Solar and Stellar Astrophysics · Physics 2023-11-07 Joaquin Zamponi , María José Maureira , Hauyu Baobab Liu , Bo Zhao , Dominique Segura-Cox , Chia-Lin Ko , Paola Caselli

Although interstellar grains are known to be aspherical, their actual shapes remain poorly constrained. We assess whether three continuous distributions of ellipsoidal shapes from the literature are suitable for describing the shapes of…

Astrophysics of Galaxies · Physics 2025-04-07 B. T. Draine , Brandon S. Hensley

The properties of polarization in scattered light by aligned ellipsoidal grains are investigated with the Fredholm integral equation method (FIM) and the T-matrix method (Tmat), and the results are applied to the observed circular…

Astrophysics of Galaxies · Physics 2010-01-15 Masafumi Matsumura , Pierre Bastien

Polarization carries information about the magnetic fields in interstellar clouds. The observations of polarized dust emission are used to study the role of magnetic fields in the evolution of molecular clouds and the initial phases of…

Astrophysics of Galaxies · Physics 2015-05-13 V. -M. Pelkonen , M. Juvela , P. Padoan

Thermal dust polarization is a powerful tool to probe magnetic fields ($\textbf{B}$) and grain properties. However, a systematic study of the dependence of dust polarization on grain properties in protostellar environments is not yet…

Astrophysics of Galaxies · Physics 2024-03-14 Nguyen Chau Giang , Thiem Hoang

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…

Astrophysics · Physics 2009-11-11 N. V. Voshchinnikov , V. B. Il'in , Th. Henning , D. N. Dubkova

We compiled the polarimetric data for a sample of lines of sight with known abundances of Mg, Si, and Fe. We correlated the degree of interstellar polarization $P$ and polarization efficiency (the ratio of $P$ to the colour excess $E(B-V)$…

Astrophysics of Galaxies · Physics 2015-06-04 N. V. Voshchinnikov , Th. Henning , M. S. Prokopjeva , H. K. Das

We explore the induction of circular polarization (CP) of near-infrared light in star-forming regions using three-dimensional radiative transfer calculations. The simulations trace the change of Stokes parameters at each…

Astrophysics of Galaxies · Physics 2020-06-24 Hajime Fukushima , Hidenobu Yajima , Masayuki Umemura

Interstellar dust grain alignment causes polarization from UV to mm wavelengths, allowing the study of the geometry and strength of the magnetic field. Over last couple of decades observations and theory have led to the establishment of the…

Polarized (sub)millimeter emission from dust grains in circumstellar disks was initially thought to be due to grains aligned with the magnetic field. However, higher resolution multi-wavelength observations along with improved models found…

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…

Astrophysics of Galaxies · Physics 2025-06-18 M. -A. Carpine , N. Ysard , A. Maury , A. Jones

We study alignment of grains by radiative torques. We found steep rise of radiative torque efficiency as grain size increases. This allows larger grains that are known to exist within molecular clouds to be aligned by the attenuated and…

Astrophysics · Physics 2009-11-11 J. Cho , A. Lazarian

Recent observation of linear optical polarization from brown dwarfs confirms the dust hypothesis in the atmospheres of brown dwarfs with effective temperature higher than 1400 K. The observed polarization could arise due to dust scattering…

Astrophysics · Physics 2009-11-07 Sujan Sengupta