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Related papers: Grain Alignment in Starless Cores

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The goals of this work are to provide NIR polarimetry of the stellar sources in the central pc at the resolution of an 8m telescope for the first time, along with new insights into the nature of the known bright bow-shock sources. We use AO…

Astrophysics of Galaxies · Physics 2015-05-28 Rainer M. Buchholz , Gunther Witzel , Rainer Schödel , Andreas Eckart , Markus Bremer , Koraljka Muzic

(abridged) We correlated near-infrared stellar H-Ks colour excesses of background stars from NTT/SOFI with the far-IR optical depth map, tauFIR, derived from Herschel 160, 250, 350, and 500 um data. The Herschel maps were also used to…

It is well known that the polarized continuum emission from magnetically aligned dust grains is determined to a large extent by local magnetic field structure. However, the observed significant anticorrelation between polarization fraction…

Astrophysics of Galaxies · Physics 2019-10-02 Patrick K. King , Che-Yu Chen , Laura M. Fissel , Zhi-Yun Li

Data from the Five College Radio Astronomy Observatory CO Mapping Survey of the Taurus molecular cloud are combined with extinction data for a sample of 292 background field stars to investigate the uptake of CO from the gas to icy grain…

Astrophysics of Galaxies · Physics 2010-07-20 D. C. B. Whittet , P. F. Goldsmith , J. L. Pineda

Aligned non-spherical dust particles polarize starlight passing through the dust cloud. They also emit polarized far infrared and sub-mm radiation. Substantial progress in understanding of grain alignment theory makes the interpretation of…

Astrophysics · Physics 2007-05-23 A. Lazarian

The alignment of interstellar dust grains with magnetic fields provides a key method for measuring the strength and morphology of the fields. In turn, this provides a means to study the role of magnetic fields from diffuse gas to dense…

Astrophysics of Galaxies · Physics 2016-02-09 John E. Vaillancourt , B-G Andersson

Magnetic fields ($\textbf{B}$) are an important factor that controls the star formation process. The leading method to observe $\textbf{B}$ is using polarized thermal emission from dust grains aligned with $\textbf{B}$. However, in dense…

Astrophysics of Galaxies · Physics 2023-06-16 Nguyen Chau Giang , Thiem Hoang , Jeong-Gyu Kim , Le Ngoc Tram

Polarization of starlight and thermal dust emission due to aligned non-spherical grains helps us to trace magnetic field (B-field) morphology in molecular clouds and to study grain alignment mechanisms. In this work, we study grain…

Astrophysics of Galaxies · Physics 2025-01-22 Saikhom Pravash , Archana Soam , Pham Ngoc Diep , Thiem Hoang , Nguyen Bich Ngoc , Le Ngoc Tram

Dust in the diffuse interstellar medium remains incompletely understood with regard to the structure, composition, size distribution, and alignment properties of the grains. Joint observations of reddening, starlight polarisation spectra,…

Astrophysics of Galaxies · Physics 2026-05-27 Ralf Siebenmorgen , Stefano Bagnulo , Lapo Fanciullo , Thomas Vannieuwenhuyse , Vincent Guillet

We present high quality near infrared imaging polarimetry of HL Tau at 0.4 to 0.6 arcsec resolution, obtained with Subaru/CIAO and UKIRT/IRCAM. 3-D Monte Carlo modelling with aligned oblate grains is used to probe the structure of the…

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

Polarimetry is one of the most informative techniques of studying magnetic fields in molecular clouds. How reliable the interpretation of the polarization maps in terms of magnetic fields is the issue that the grain alignment theory…

Astrophysics · Physics 2016-08-30 A. Lazarian , J. Cho

A quantitative interpretation of the observed relation between the interstellar linear polarization curve parameters $K$ and $\lambda_{\max}$ characterizing the width and the wavelength of a polarization maximum, respectively, is given. The…

Astrophysics of Galaxies · Physics 2015-06-15 N. V. Voshchinnikov , H. K. Das , I. S. Yakovlev , V. B. Il'in

Interstellar dust grains are often aligned. If the grain alignment direction varies along the line of sight, the thermal emission becomes circularly-polarized. In the diffuse interstellar medium, the circular polarization at far-infrared…

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

A previous study (Paper I) investigated the polarization properties of a variety of simple convex grain shapes, some of which were found to be consistent with the observed polarization properties of interstellar dust from far-ultraviolet to…

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

The extinction curve of interstellar dust in the dense molecular cloud cores is crucial for understanding dust properties, particularly size distribution and composition. We investigate the infrared extinction law in four nearby isolated…

Astrophysics of Galaxies · Physics 2024-11-04 Jun Li , Bingqiu Chen , Biwei Jiang , He Zhao , Botao Jiang , Xi Chen

Context. Sunlight scattered from the surface of an airless body is generally partially polarized, and the corresponding polarization state includes information about the scattering surface, such as albedo, surface grain sizes, composition,…

Earth and Planetary Astrophysics · Physics 2024-04-19 Yoonsoo P. Bach , Masateru Ishiguro , Jun Takahashi , Jooyeon Geem , Daisuke Kuroda , Hiroyuki Naito , Jungmi Kwon

Galactic dust emission is polarized at unexpectedly high levels, as revealed by Planck. The origin of the observed $\simeq 20\%$ polarization fractions can be identified by characterizing the properties of optical starlight polarization in…

Astrophysics of Galaxies · Physics 2019-04-17 G. V. Panopoulou , B. S. Hensley , R. Skalidis , D. Blinov , K. Tassis

We study infrared emission of 17 isolated, diffuse clouds with masses of order solar masses, to test the hypothesis that grain property variations cause the apparently low gas-to-dust ratios that have been measured in those clouds. Maps of…

Astrophysics of Galaxies · Physics 2018-08-13 William T. Reach , Jean-Philippe Bernard , Thomas Jarrett , Carl Heiles

Context. Anomalous microwave emission (AME) is a component of interstellar medium emission peaking at 10-60 GHz. Its polarization is both a CMB foreground and a probe of the alignment physics of very small dust grains. Aims. We quantify…

Astrophysics of Galaxies · Physics 2026-04-30 Boy Lankhaar