English
Related papers

Related papers: Cosmic rays and grain alignment

200 papers

Interstellar dust grains exhibit complex dynamics which is essential for understanding many key interstellar processes that involve dust, including grain alignment, grain growth, grain shattering etc. Grain rotational and translational…

Astrophysics · Physics 2007-05-23 A. Lazarian , Huirong Yan

Linearly polarized, non-masing, rotational lines have been detected for the first time in the interstellar medium. This effect occurs in molecular clouds with a magnetic field, and traces the field direction, offering an alternative…

Astrophysics · Physics 2009-10-31 J. S. Greaves , W. S. Holland , P. Friberg , W. R. F. Dent

Magnetic fields (B-fields) in galaxies have recently been traced using far-infrared and sub-mm polarimetric observations with SOFIA, JCMT, and ALMA. The main assumption is that dust grains are magnetically aligned with the local B-field in…

Astrophysics of Galaxies · Physics 2024-03-01 Enrique Lopez-Rodriguez , Le Ngoc Tram

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…

Observations of gaseous complex organic molecules (COMs) in cold starless and prestellar cloud cores require efficient desorption of the COMs and their parent species from icy mantles on interstellar grains. With a simple astrochemical…

Astrophysics of Galaxies · Physics 2022-07-04 Juris Kalvāns , Kedron Silsbee

Magnetic fields play a crucial role in various astrophysical processes, including star formation, accretion of matter, transport processes (e.g., transport of heat), and cosmic rays. One of the easiest ways to determine the magnetic field…

Astrophysics · Physics 2009-11-13 A. Lazarian

We argue that charged dust grains could significantly impact the confinement and transport of galactic cosmic rays. For sub-GeV to ~1000GeV cosmic rays, small-scale parallel Alfv\'en waves, which isotropize cosmic rays through gyro-resonant…

High Energy Astrophysical Phenomena · Physics 2021-02-03 Jonathan Squire , Philip F Hopkins , Eliot Quataert , Philipp Kempski

We investigate ionization and heating of gas in the dense, shielded clumps/cores of molecular clouds bathed by an influx of energetic, charged cosmic rays (CRs). These molecular clouds have complex structures, with substantial variation in…

Astrophysics of Galaxies · Physics 2021-06-02 Ellis R. Owen , Alvina Y. L. On , Shih-Ping Lai , Kinwah Wu

We apply the theory of radiative torque (RAT) alignment for studying protoplanetary disks around a T-Tauri star and perform 3D radiative transfer calculations to provide the expected maps of polarized radiation to be compared with…

Earth and Planetary Astrophysics · Physics 2017-04-19 Ryo Tazaki , Alexandre Lazarian , Hideko Nomura

The macroscopic behaviour of cosmic rays in turbulent magnetic fields is discussed. An implementation of anisotropic diffusion of cosmic rays with respect to the magnetic field in a non-conservative, high-order, finite-difference…

Astrophysics · Physics 2008-11-26 A. P. Snodin , Axel Brandenburg , A. J. Mee , Anvar Shukurov

Interstellar dust grain growth in dense clouds and protoplanetary disks, even moderate, affects the observed interstellar ice profiles as soon as a significant fraction of dust grains is in the size range close to the wave vector at the…

Astrophysics of Galaxies · Physics 2022-10-26 Emmanuel Dartois , Jennifer A. Noble , Nathalie Ysard , Karine Demyk , Marin Chabot

The polarization spectrum, or wavelength dependence of the polarization fraction, of interstellar dust emission provides important insights into the grain alignment mechanism of interstellar dust grains. We investigate the far-infrared…

Abundances and partitioning of ices and gases produced by gas-grain chemistry are governed by adsorption and desorption on grains. Understanding astrophysical observations rely on laboratory measurements of adsorption and desorption rates…

Astrophysics of Galaxies · Physics 2021-02-22 Carine Laffon , Daniel Ferry , Olivier Grauby , Philippe Parent

We present a new method for using the observed starlight polarization and polarized submm emission to constrain the shapes and porosities of interstellar grains. We present the modified picket fence approximation (MPFA), and verify that it…

Astrophysics of Galaxies · Physics 2021-10-04 B. T. Draine , Brandon S. Hensley

In regions where stars form, variations in density and temperature can cause gas to freeze-out onto dust grains forming ice mantles, which influences the chemical composition of a cloud. The aim of this paper is to understand in detail the…

Solar and Stellar Astrophysics · Physics 2017-11-08 S. Cazaux , R. Martin-Domenech , Y. J. Chen , G. M. Munoz Caro , C. Gonzalez Diaz

Cosmic rays (CRs) are a plausible mechanism for launching winds of cool material from the discs of star-forming galaxies. However, there is no consensus on what types of galaxies likely host CR-driven winds, or what role these winds might…

Astrophysics of Galaxies · Physics 2021-03-03 Roland M. Crocker , Mark R. Krumholz , Todd A. Thompson

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

Among the most puzzling questions in climate change is that of solar-climate variability, which has attracted the attention of scientists for more than two centuries. Until recently, even the existence of solar-climate variability has been…

Atmospheric and Oceanic Physics · Physics 2011-08-31 Jasper Kirkby

Observations of the cores of nearby galaxy clusters show H$\alpha$ and molecular emission line filaments. We argue that these are the result of {\em local} thermal instability in a {\em globally} stable galaxy cluster core. We present…

Astrophysics of Galaxies · Physics 2015-05-18 Prateek Sharma , Ian J. Parrish , Eliot Quataert

We report the first measurement of polarized thermal dust emission toward the entire early and massive Infrared Dark Cloud G11.11$-$0.12 taken by the polarimeter SOFIA/HAWC+ at 214 $\mu m$ wavelength. Magnetic fields (B-fields) obtained…

‹ Prev 1 4 5 6 7 8 10 Next ›