Far-infrared Polarization of the Supernova Remnant Cassiopeia A with SOFIA HAWC+

Abstract

We present polarization observations of the young supernova remnant (SNR) Cas A using the High-resolution Airborne Wideband Camera-Plus (HAWC+) instrument onboard the Stratospheric Observatory for Infrared Astronomy (SOFIA). The polarization map at 154 microns reveals dust grains with strong polarization fractions (5 - 30 percent), supporting previous measurements made over a smaller region of the remnant at 850 microns. The 154 microns emission and the polarization signal is coincident with a region of cold dust observed in the southeastern shell and in the unshocked central ejecta. The highly polarized far-IR emission implies the grains are large (greater than 0.14 microns) and silicate-dominated. The polarization level varies across the SNR, with an inverse correlation between the polarization degree and the intensity and smaller polarization angle dispersion for brighter SNR emission. Stronger polarization is detected between the bright structures. This may result from a higher collision rate between the gas and dust producing a lower grain alignment efficiency where the gas density is higher. We use the dust emission to provide an estimate of the magnetic field strength in Cas A using the Davis-Chandrasekhar-Fermi method. The high polarization level is direct evidence that grains are highly elongated and strongly aligned with the magnetic field of the SNR. The dust mass from the polarized region is 0.14+-0.04 Msun, a lower limit of the amount of dust present within the ejecta of Cas A. This result strengthens the hypothesis that core-collapse SNe are an important contributor to the dust mass in high redshift galaxies.

arXiv commentMNRAS, accepted (18 pages with 14 figures)

References in corpus (76)

• New Interstellar Dust Models Consistent with Extinction, Emission, and Abundance Constraints
• Dust Formation in Primordial Type II Supernovae
• Radiative torques: Analytical Model and Basic Properties
• The evolution of amorphous hydrocarbons in the ISM: dust modelling from a new vantage point
• Planck intermediate results. XIX. An overview of the polarized thermal emission from Galactic dust
• Dust Formation and Survival in Supernova Ejecta
• The Expansion Asymmetry and Age of the Cassiopeia A Supernova Remnant
• Evolution of Dust in Primordial Supernova Remnants: Can Dust Grains Formed in the Ejecta Survive and be Injected into the Early Interstellar Medium?
• Radiative Torques on Interstellar Grains: II. Grain Alignment
• The Evolution of Dust in the Early Universe with Applications to the Galaxy SDSS J1148+5251
• Dust Formation In Early Galaxies
• Herschel-ATLAS: Rapid evolution of dust in galaxies in the last 5 billion years
• Freshly Formed Dust in the Cassiopeia A Supernova Remnant as Revealed by the Spitzer Space Telescope
• The Origin of Cosmic Dust
• FAR-INFRARED SPECTRAL OBSERVATIONS OF THE GALAXY BY COBE
• Studies of regular and random magnetic fields in the ISM: statistics of polarization vectors and the Chandrasekhar-Fermi technique
• Production of dust by massive stars at high redshift
• A Herschel PACS and SPIRE study of the dust content of the Cassiopeia A supernova remnant
• A stubbornly large mass of cold dust in the ejecta of Supernova 1987A
• A Cool Dust Factory in the Crab Nebula: A Herschel Study of the Filaments
• Observational signatures of particle acceleration in supernova remnants
• Constraints on the Progenitor of Cassiopeia A
• Planck intermediate results. XX. Comparison of polarized thermal emission from Galactic dust with simulations of MHD turbulence
• The Three-Dimensional Structure of Cassiopeia A
• A unified model of grain alignment: radiative alignment of interstellar grains with magnetic inclusions
• Condensation of dust in the ejecta of type II-P supernovae
• The dust mass in Cassiopeia A from a spatially resolved Herschel analysis
• The dust budget crisis in high-redshift submillimetre galaxies
• Dust production 680-850 million years after the Big Bang
• Formation and Evolution of Dust in Type IIb Supernova with Application to the Cassiopeia A Supernova Remnant
• The dust and gas content of the Crab Nebula
• Cassiopeia A: dust factory revealed via submillimetre polarimetry
• Dust models compatible with Planck intensity and polarization data in translucent lines of sight
• No cold dust within the supernova remnant Cassiopeia A
• Dust grains from the heart of supernovae
• Formation of Dust in the Ejecta of Type Ia Supernovae
• Alignment of Irregular Grains by Mechanical Torques
• Submillimeter and Far-Infrared Polarimetric Observations of Magnetic Fields in Star-Forming Regions
• Magnetic fields in massive star forming regions
• Spectropolarimetry of the 3.4 micron Feature in the Diffuse ISM toward the Galactic Center Quintuplet Cluster
• Dust survival rates in clumps passing through the Cas A reverse shock I: results for a range of clump densities
• Spitzer Spectral Mapping of Supernova Remnant Cassiopeia A
• Interstellar and Ejecta Dust in the Cas A Supernova Remnant
• Iron and silicate dust growth in the Galactic interstellar medium: clues from element depletions
• Spitzer IRAC Images and Sample Spectra of Cassiopeia A's Explosion
• A Massive Shell of Supernova-formed Dust in SNR G54.1+0.3
• Interstellar Dust Models and Evolutionary Implications
• The Three-Dimensional Structure of Interior Ejecta in Cassiopeia A at High Spectral Resolution
• Grain alignment and disruption by radiative torques in dense molecular clouds and implication for polarization holes
• A Dust Twin of Cas A: Cool Dust and 21-micron Silicate Dust Feature in the Supernova Remnant G54.1+0.3
• Supernova dust yields: the role of metallicity, rotation, and fallback
• Evidence for proton acceleration up to TeV energies based on VERITAS and Fermi-LAT observations of the Cas A SNR
• SOFIA mid-infrared observations of Supernova 1987A in 2016 --- forward shocks and possible dust re-formation in the post-shocked region?
• Molecular nucleation theory of dust formation in core-collapse supernovae applied to SN 1987A
• Physical Model of Dust Polarization by Radiative Torque Alignment and Disruption and Implications for Grain Internal Structures
• SILCC-Zoom: Polarisation and depolarisation in molecular clouds
• Carbon Monoxide in the Type Ic SN 2000ew
• Constraining dust formation in high-redshift young galaxies
• The dust content of the Crab Nebula
• Intrinsic polarisation of elongated porous dust grains
• Mapping the magnetic field in the Taurus/B211 filamentary cloud with SOFIA HAWC+ and comparing with simulation
• The JCMT BISTRO Survey: The Distribution of Magnetic Field Strengths towards the OMC-1 Region
• Near-Infrared Synchrotron Emission from Cas A
• Using the Starlight Polarization Efficiency Integral to Constrain Shapes and Porosities of Interstellar Grains
• Nucleosynthetic Layers in the Shocked Ejecta of Cassiopeia A
• Effects of grain alignment with magnetic fields on grain growth and the structure of dust aggregates
• Observations of magnetic fields surrounding LkH$\alpha$ 101 taken by the BISTRO survey with JCMT-POL-2
• Galactic Center Extinction: Evidence for Metallic Needles in the General Interstellar Medium
• Dust survival rates in clumps passing through the Cas A reverse shock -- II. The impact of magnetic fields
• Dust destruction and survival in the Cassiopeia A reverse shock
• On the Shapes of Interstellar Grains: Modeling Extinction and Polarization by Spheroids and Continuous Distributions of Ellipsoids
• SOFIA observations of 30 Doradus: I -- Far-Infrared dust polarization and implications for grain alignment and disruption by radiative torques
• Polarised emission from aligned dust grains in nearby galaxies: predictions from the Auriga simulations
• Mapping the spectral index of Cas A: evidence for flattening from radio to infrared
• CO J=2-1 Observations toward the Supernova Remnant G54.1+0.3
• SOFIA/HAWC+ observations of the Crab Nebula: dust properties from polarised emission