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Related papers: Grain Alignment by Radiative Torques in Special Co…

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Iron inclusions embedded inside dust grains play a crucial role in both internal alignment (IA) via Barnett relaxation and external alignment via the MAgnetically Enhanced RAdiative Torque (MRAT) mechanism. Moreover, inelastic relaxation is…

Astrophysics of Galaxies · Physics 2025-02-10 Nguyen Chau Giang , V. J. M. Le Gouellec , Thiem Hoang , A. J. Maury , P. Hennebelle

Several of the current and next-generation cosmic microwave background (CMB) experiments have polarimetric capability, promising to add to the finesse of precision cosmology. One of the contaminating Galactic foregrounds is thermal emission…

Astrophysics · Physics 2009-11-11 P. G. Martin

Tons of space particles enter the Earth atmosphere every year, being detected when they produce fireballs, meteor showers, or when they impact the Earth surface. Particle detection in the showers could also be attempted from space using…

Earth and Planetary Astrophysics · Physics 2023-10-16 Jennifer López-Viejobueno , Leire Beitia-Antero , Ana I. Gómez de Castro

Spatially resolved polarized (sub-)mm emission has been observed for example in the protoplanetary disk around HL Tau. Magnetically aligned grains are commonly interpreted as the source of polarization. However, self-scattering by large…

Earth and Planetary Astrophysics · Physics 2016-08-31 A. Pohl , A. Kataoka , P. Pinilla , C. P. Dullemond , Th. Henning , T. Birnstiel

Paramagnetic alignment of non-spherical dust grains rotating at thermal velocities is studied. The analytical solution is found for the alignment measure of oblate grains. Perturbative approach is used for solving the problem. It is shown…

Astrophysics · Physics 2009-10-28 A. Lazarian

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…

The alignment of interstellar dust grains is described by the joint distribution function for certain ``internal'' and ``external'' variables, where the former describe the orientation of a grain's axes with respect to its angular momentum,…

Astrophysics · Physics 2015-06-24 W. G. Roberge

We present new multicolor photo-polarimetry of stars behind the Southern Coalsack. Analyzed together with multiband polarization data from the literature, probing the Chamaeleon I, Musca, rho Opiuchus, R CrA and Taurus clouds, we show that…

Astrophysics · Physics 2009-06-23 B-G Andersson , S. B. Potter

We have investigated the grain alignment and dust properties towards the direction of the cluster NGC 2345 using the multi-band optical polarimetric observations. For the majority of the stars, the observed polarization is found to be due…

Astrophysics of Galaxies · Physics 2022-06-01 Sadhana Singh , Jeewan C. Pandey , Thiem Hoang

Interstellar polarization at far-infrared through millimeter wavelengths (0.1 - 1 mm) is primarily due to thermal emission from dust grains aligned with magnetic fields. This mechanism has led to studies of magnetic fields in a variety of…

Astrophysics of Galaxies · Physics 2009-04-14 John E. Vaillancourt

(Sub)millimeter dust polarization in protoplanetary disks has revealed the presence of large (~ 100 um) dust grains that are aligned along their long axis following the azimuthal direction of the disk. The novel Badminton Birdie-like…

(Aims) In this work, we predict the far-infrared polarisation signal emitted by non-spherical dust grains in nearby galaxies. We determine the angular resolution and sensitivity required to study the magnetic field configuration in these…

Context. Grains in circumstellar disks are believed to grow by mutual collisions and subsequent sticking due to surface forces. Results of many fields of research involving circumstellar disks, such as radiative transfer calculations, disk…

Earth and Planetary Astrophysics · Physics 2010-09-20 T. Birnstiel , C. W. Ormel , C. P. Dullemond

In this paper we study the effects of inclusions and porosities on the emission properties of silicate grains and compare the model curves with the observed infrared emission from circumstellar dust. We calculate the absorption efficiency…

Solar and Stellar Astrophysics · Physics 2015-03-17 D. B. Vaidya , Ranjan Gupta

A systematic torque from anisotropic radiation can rapidly spin up irregular grains to the point of breakup. We apply the standard theory of rotational disruption from radiative torques to solar system grains, finding that grains with radii…

Earth and Planetary Astrophysics · Physics 2025-03-19 Kedron Silsbee , Brandon S. Hensley , Jamey R. Szalay , Petr Pokorný , Jeong-Gyu Kim

It is shown, that mechanical alignment can be efficient for suprathermally rotating grains, provided that they drift with supersonic velocities. Such a drift should be widely spread due to both Alfv\'{e}nic waves and ambipolar diffusion.…

Astrophysics · Physics 2015-06-24 A. Lazarian

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

Aligned interstellar grains produce polarized extinction (observed at wavelengths from the far-ultraviolet to the mid-infrared), and polarized thermal emission (observed at far-infrared and submm wavelengths). The grains must be quite…

Astrophysics of Galaxies · Physics 2025-04-07 B. T. Draine

Circumstellar disk dust polarization in the (sub)millimeter is, for the most part, not from dust grain alignment with magnetic fields but rather indicative of a combination of dust self-scattering with a yet unknown alignment mechanism that…

Aims: In this paper we present a case study to investigate conditions necessary to detect a characteristic magnetic field substructure embedded in a large-scale field. A helical magnetic field with a surrounding hourglass shaped field is…

Solar and Stellar Astrophysics · Physics 2017-07-12 S. Reissl , D. Seifried , S. Wolf , R. Banerjee , R. S. Klessen