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Related papers: Grain Alignment and CMB Polarization Studies

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The dependence of polarization fraction $p$ on total intensity $I$ in polarized submillimeter emission measurements is typically parameterized as $p\propto I^{-\alpha}$ $(\alpha \leq 1)$, and used to infer dust grain alignment efficiency in…

If aspherical dust grains are immersed in an anisotropic radiation field, their temperature depends on the cross-sections projected in the direction of the anisotropy.It was shown that the temperature difference produces polarized thermal…

Astrophysics · Physics 2009-10-31 Takashi Onaka

The DASI discovery of CMB polarization, confirmed by WMAP, has opened a new chapter in cosmology. Most of the useful information about inflationary gravitational waves and reionization is on large angular scales where Galactic foreground…

Astrophysics · Physics 2007-05-23 Angelica de Oliveira-Costa

We discuss the dynamics of dust grains subjected to uncompensated torques arising from H_2 formation. In particular, we discuss grain dynamics when a grain spins down and goes through a ``crossover''. As first pointed out by Spitzer &…

Astrophysics · Physics 2009-10-28 A. Lazarian , B. T. Draine

The size of dust grains, $a$, is key to the physical and chemical processes in circumstellar disks, but observational constraints of grain size remain challenging. (Sub)millimeter continuum observations often show a percent-level…

The mechanisms causing millimeter-wave polarization in protoplanetary disks are under debate. To disentangle the polarization mechanisms, we observe the protoplanetary disk around HL Tau at 3.1 mm with the Atacama Large…

Earth and Planetary Astrophysics · Physics 2017-07-26 Akimasa Kataoka , Takashi Tsukagoshi , Adriana Pohl , Takayuki Muto , Hiroshi Nagai , Ian W. Stephens , Kohji Tomisaka , Munetake Momose

The primary source of systematic uncertainty in the quest for the B-mode polarization of the Cosmic Microwave Background (CMB) introduced by primordial gravitational waves is polarized thermal emission from Galactic dust. Therefore,…

High resolution (sub-)millimeter polarization observations have opened a new era in the understanding of how B-fields are organized in star forming regions, unveiling an intricate interplay between the B-fields and the gas in protostellar…

Astrophysics of Galaxies · Physics 2022-12-14 Valeska Valdivia , Anaëlle Maury , Patrick Hennebelle

The alignment of dust grains with the ambient magnetic field produces polarization of starlight as well as thermal dust emission. Using the archival SOFIA/HAWC+ polarimetric data observed toward $\rho$ Ophiuchus (Oph) A cloud hosted by a B…

Astrophysics of Galaxies · Physics 2021-01-25 Le Ngoc Tram , Thiem Hoang , Hyeseung Lee , Fabio Santos , Archana Soam , Pierre Lesaffre , Antoine Gusdorf , William Reach

The quantization of energy levels in very nanoparticles suppresses dissipative processes that convert grain rotational kinetic energy into heat. For grains small enough to have GHz rotation rates, the suppression of dissipation can be…

Astrophysics of Galaxies · Physics 2017-04-05 B. T. Draine , Brandon S. Hensley

The optical and magnetic properties of dust grains are reviewed, as they relate to the problem of interstellar grain alignment. Grain geometry plays an important role in determining the optical properties, and scattering and absorption of…

Astrophysics · Physics 2007-05-23 B. T. Draine

The polarization of the Cosmic Microwave Background (CMB)is a powerful observational tool at hand for modern cosmology. It allows to break the degeneracy of fundamental cosmological parameters one cannot obtain using only anisotropy data…

Astrophysics · Physics 2007-05-23 M. V. Sazhin , G. Sironi , O. S. Khovanskaya

The radiative torque (RAT) mechanism is the most promising way of explaining observed polarization arising from aligned grains. We explore the efficiency of the grain alignment by an anisotropic radiation flow for an extensive ensemble of…

Astrophysics of Galaxies · Physics 2019-06-26 Joonas Herranen , Alex Lazarian , Thiem Hoang

(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…

We present a three-dimensional model of polarised galactic dust emission that takes into account the variation of the dust density, spectral index and temperature along the line of sight, and contains randomly generated small scale…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-31 Ginés Martínez-Solaeche , Ata Karakci , Jacques Delabrouille

Polarized thermal emission from Galactic dust is the dominant foreground for CMB polarization measurements at high frequencies, with its statistical properties set by the interplay between turbulence and magnetic fields in the multiphase…

Astrophysics of Galaxies · Physics 2026-01-27 Yue Hu , Bao Truong , Thiem Hoang , Le Ngoc Tram

The coming flood of CMB polarization experiments, spurred by the recent detection of CMB polarization by DASI and WMAP, will be confronted by many new analysis tasks specific to polarization. For the analysis of CMB polarization data sets,…

With polarization of the cosmic microwave background (CMB) now detected, and confirmed by several independent experiments, the next goal is to characterise accurately its statistical properties. In these lecture notes we review the physical…

Astrophysics · Physics 2018-05-02 Anthony Challinor

We estimate the dust polarized emission in our galaxy at high galactic latitudes, which is the dominant foreground for measuring CMB polarization using the high frequency instrument (HFI) aboard Planck surveyor. We compare it with the level…

Astrophysics · Physics 2007-05-23 Shiv K. Sethi , Simon Prunet , F. R. Bouchet

Dust grains drift through the interstellar medium (ISM) and are aligned with the magnetic field. Here we study the effect of grain alignment and grain motion on grain growth in molecular clouds (MCs). We first discuss the characteristic…

Astrophysics of Galaxies · Physics 2022-04-06 Thiem Hoang
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