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Related papers: Grain Alignment in Starless Cores

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Deep JHKs photometry was obtained towards eight dense molecular cores and J-H vs. H-Ks color-color plots are presented. Our photometry, sensitive to the detection of a 1 solar mass, 1 X 10^6 year old star through approx. 35 - 50 magnitudes…

Astrophysics · Physics 2009-11-07 David C. Murphy , Philip C. Myers

Interstellar polarization in the optical/infrared has long been known to be due to asymmetrical dust grains aligned with the magnetic field and can potentially provide a resource effective way to probe both the topology and strength of the…

Astrophysics of Galaxies · Physics 2012-08-23 B. -G. Andersson

Polarization of optical starlight and far-infrared thermal dust emission due to alignment of interstellar grains offers a powerful window to study magnetic fields in the various astrophysical environments, from the diffuse interstellar…

Astrophysics of Galaxies · Physics 2017-04-07 Thiem Hoang

In the standard picture of isolated star formation, dense ``starless'' cores are formed out of magnetic molecular clouds due to ambipolar diffusion. Under the simplest spherical geometry, I demonstrate that ``starless'' cores formed this…

Astrophysics · Physics 2009-10-31 Zhi-Yun Li

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 investigate the shape of the extinction law in two 1-degree square fields of the Perseus Molecular Cloud complex. We combine deep red-optical (r, i, and z-band) observations obtained using Megacam on the MMT with UKIDSS near-infrared (J,…

Astrophysics of Galaxies · Physics 2015-06-11 Jonathan B. Foster , Kaisey S. Mandel , Jaime E. Pineda , Kevin R. Covey , Héctor G. Arce , Alyssa A. Goodman

(abridged) The polarized thermal radiation at far infrared and submillimeter wavelengths from dust grains in interstellar clouds with irregular magnetic fields is simulated. We show that the polarization properties of quiescent clouds and…

Astrophysics · Physics 2009-11-10 D. S. Wiebe , W. D. Watson

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

The structure of magnetic fields within protostellar disks may be studied via polarimetry provided that grains are aligned in respect to magnetic field within the disks. We explore alignment of dust grains by radiative torque in T Tauri…

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

We study the alignment and rotational disruption of dust grains at the centre of our Galaxy using polarized thermal dust emission observed by SOFIA/HAWC+ and JCMT/SCUPOL at 53, 216, and 850 $\mu$m. We analyzed the relationship between the…

Astrophysics of Galaxies · Physics 2023-05-01 M. S. Akshaya , Thiem Hoang

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

We present a study of the polarizing power of the dust in cold dense regions (dark clouds) compared to that of dust in the general interstellar medium (ISM). Our study uses new polarimetric, optical, and spectral classification data for 36…

Astrophysics · Physics 2009-10-30 Hector G. Arce , Alyssa A. Goodman , Pierre Bastien , Nadine Manset , Mathew Sumner

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…

Our aim is to study the polarization of thermal dust emission to see if the alignment of grain by radiative torques could explain the observed relation between the degree of polarization and the intensity in dense cores. Predictions are…

Astrophysics · Physics 2009-11-11 V. -M. Pelkonen , M. Juvela , P. Padoan

Dusty starless cores play an important role in regulating the initial phases of the formation of stars and planets. In their interiors, dust grains coagulate and ice mantles form, thereby changing the millimeter emissivities and hence the…

Context. The largest grains (0.5-1 micron) in the interstellar size distribution are efficient in scattering near- and mid-infrared radiation. These wavelengths are therefore particularly well suited to probe the still uncertain high-end of…

Astrophysics of Galaxies · Physics 2015-06-17 M. Andersen , J. Steinacker , W-F. Thi , L. Pagani , A. Bacmann , R. Paladini

We combined sensitive near-infrared data obtained with ground-based imagers on the ESO NTT and VLT telescopes with space mid-infrared data acquired with the IRAC imager on the Spitzer Space Telescope to calculate the extinction law…

Astrophysics · Physics 2015-05-13 C. Román-Zúñiga , C. Lada , A. Muench , J. Alves

The purpose of the investigation is to probe the dust properties inside a molecular cloud, how particle grow and how the presence of ice coatings may change the overall shape of the extinction curve. Field stars can be used to probe the…

Astrophysics of Galaxies · Physics 2015-06-03 Sven Olofsson , Göran Olofsson

Interstellar grain alignment studies are currently experiencing a renaissance due to the development of a new quantitative theory based on Radiative Alignment Torques (RAT). One of the distinguishing predictions of this theory is a…

Astrophysics of Galaxies · Physics 2015-05-30 B-G Andersson , O. Pintado , S. B. Potter , V. Straizys , M. Charcos-Llorens

We model the polarized thermal dust emission from protostellar cores that are assembled by super-sonic turbulent flows in molecular clouds. Self-gravitating cores are selected from a three dimensional simulation of super-sonic and…