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Related papers: Polarimetric studies of comet Halley

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In the present work, the non-spherical dust grain characteristics of comet Hale-Bopp are studied using the T-matrix method and the modified power law distribution function. It is found that the observed data fits very well with the power…

Astrophysics · Physics 2007-05-23 H. S. Das , A. K. Sen

Observational data for dusty comets are summarized and systemized. The dependence of the linear polarization on various parameters (the phase angle, wavelength, etc.) is analyzed. An ensemble of aligned spheroidal particles having various…

Astrophysics · Physics 2007-05-23 D. A. Semenov , N. V. Voshchinnikov

Recently, the result obtained from `Stardust' mission suggests that the overall ratio of compact to aggregate particles is 65:35 (or 13:7) for Comet 81P/Wild 2 (Burchell et al. 2008). In the present work, we propose a model which considers…

Earth and Planetary Astrophysics · Physics 2015-05-28 H. S. Das , D. Paul , A. Suklabaidya , A. K. Sen

The azimuthal polarization patterns observed in some protoplanetary disks by ALMA at millimeter wavelength have raised doubts about their being produced by dust grains aligned with the magnetic field lines. These conclusions were based on…

Astrophysics of Galaxies · Physics 2020-02-26 V. Guillet , J. M. Girart , A. J. Maury , F. O. Alves

In the present work, the non-spherical dust grain characteristics of comet Levy 1990XX with different silicate grain compositions (both pyroxene and olivine) are studied using the T-matrix method. Considering amorphous pyroxene grain…

Astrophysics · Physics 2007-05-23 H. S. Das , R. Bhattacharjee , B. K. Sinha , A. K. Sen

Telescopes are now able to resolve dust polarization across circumstellar disks at multiple wavelengths, allowing the study of the polarization spectrum. Most disks show clear evidence of dust scattering through their unidirectional…

Solar and Stellar Astrophysics · Physics 2022-04-27 Zhe-Yu Daniel Lin , Zhi-Yun Li , Haifeng Yang , Ian Stephens , Leslie Looney , Rachel Harrison , Manuel Fernández-López

Polarization is a unique tool to study the properties of dust grains of protoplanetary disks and detail the initial conditions of planet formation. Polarization around HL Tau was previously imaged using the Atacama Large…

ALMA observations revealed recently polarised radiation of several protoplanetary disks in the (sub-)millimetre wavelength range. Besides self-scattering of large particles, thermal emission by elongated grains is a potential source for the…

Earth and Planetary Astrophysics · Physics 2019-07-10 Florian Kirchschlager , Gesa H. -M. Bertrang , Mario Flock

Composition of Comet dust obtained by the dust impact analyser on the Halley probes indicated that the comet dust is a mixure of silicate and carbonaceous material. The collected interplanetary dust particles (IDP's) are fluffy and…

Astrophysics · Physics 2009-11-11 Ranjan Gupta , D. B. Vaidya , J. S. Dobbie , P. Chylek

We interpret the relation between the polarizing efficiency $P_{\max}/E(B-V)$ and the wavelength of the maximum polarization $\lambda_{\max}$ observed for 17 objects (including 243 stars) separated into two groups: "dark clouds" and "open…

Astrophysics of Galaxies · Physics 2016-10-12 N. V. Voshchinnikov , V. B. Il'in , H. K. Das

Polarization at millimeter wavelengths provides a powerful diagnostic of dust grain properties in protoplanetary disks. Standard models based on solid spherical grains often struggle to reproduce the observed polarization fractions and…

We aim to investigate the polarization properties of a starless core in a very early evolutionary stage. Linear polarization data reveal the properties of the dust grains in the distinct phases of the interstellar medium. Our goal is to…

Solar and Stellar Astrophysics · Physics 2014-09-17 Felipe Alves , Pau Frau , Josep M. Girart , Gabriel A. P. Franco , Fábio P. Santos , Helmut Wiesemeyer

In our present study, the observed linear polarization data of comet Hyakutake are studied at wavelengths $\lambda=0.365\mu m$, $\lambda=0.485\mu m$ and 0.684$\mu m$ through simulations using Ballistic Particle-Cluster Aggregate and…

Earth and Planetary Astrophysics · Physics 2015-05-14 H. S. Das , A. Suklabaidya , S. Datta Majumder , A. K. Sen

The HD 163296 disk shows ring and gap substructures with ALMA observations. In addition, this is the only disk where the rings and gaps are spatially resolved in millimeter-wave polarization measurements. In this paper, we conduct radiative…

Earth and Planetary Astrophysics · Physics 2020-01-08 Satoshi Ohashi , Akimasa Kataoka

Dust polarization at (sub)millimeter wavelengths has been observed for many protoplanetary disks. Theoretically, multiple origins potentially contribute to the polarized emission but it is still uncertain what mechanism is dominant in disk…

Earth and Planetary Astrophysics · Physics 2021-03-03 Tomohiro Mori , Akimasa Kataoka

The most successful model of comet dust presents comet particles as aggregates of submicron grains. It qualitatively explains the spectral and angular change in the comet brightness and polarization and is consistent with the thermal…

Earth and Planetary Astrophysics · Physics 2015-05-14 L. Kolokolova , H. Kimura

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…

Recent observation of 850 micron sub-mm polarization from T Tauri disks opens up the possibility of studying magnetic field structure within protostellar disks. The degree of polarization is around 3 % and the direction of polarization is…

Solar and Stellar Astrophysics · Physics 2009-01-21 Jungyeon Cho , A. Lazarian

We present polarimetric data of CW Tau and DG Tau, two well-known Class II disk/jet systems, obtained with the Atacama Large Millimeter/submillimeter Array at 870 $\mu$m and 0."2 average resolution. In CW Tau, the total and polarized…

Grain alignment theory has reached the stage where quantitative predictions of the degree of alignment and its variations with optical depth are possible. With the goal of studying the effect of clumpiness on the sub-millimeter and far…

Astrophysics · Physics 2011-02-11 T. J. Bethell , A. Chepurnov , A. Lazarian , J. Kim
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