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Title: MAGNETIC FIELD COMPONENTS ANALYSIS OF THE SCUPOL 850 μm POLARIZATION DATA CATALOG

We present an extensive analysis of the 850 μm polarization maps of the SCUBA Polarimeter Legacy (SCUPOL) Catalogue produced by Matthews et al., focusing exclusively on the molecular clouds and star-forming regions. For the sufficiently sampled regions, we characterize the depolarization properties and the turbulent-to-mean magnetic field ratio of each region. Similar sets of parameters are calculated from two-dimensional synthetic maps of dust-emission polarization produced with three-dimensional magnetohydrodynamics (MHD) numerical simulations scaled to the S106, OMC-2/3, W49, and DR21 molecular cloud polarization maps. For these specific regions, the turbulent MHD regimes retrieved from the simulations, as described by the turbulent Alfvén and Sonic Mach numbers, are consistent within a factor one to two with the values of the same turbulent regimes estimated from the analysis of Zeeman measurements data provided by Crutcher. Constraints on the values of the inclination angle α of the mean magnetic field with respect to the line of sight are also given. The values obtained from the comparison of the simulations with the SCUPOL data are consistent with the estimates made by using two observational methods provided by other authors. Our main conclusion is that simple, ideal, isothermal, and non-self-gravitating MHD simulations are sufficient in ordermore » to describe the large-scale observed physical properties of the envelopes of this set of regions.« less
Authors:
 [1] ;  [2] ;  [3] ; ;  [4]
  1. Department of Physics and Astronomy, University College London, Kathleen Lonsdale Building, Gower Place, London WC1E 6BT (United Kingdom)
  2. SUPA, School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9SS (United Kingdom)
  3. Universidade de São Paulo, Escola de Artes, Ciências e Humanidades Rua Arlindo Béttio, No. 1000, Ermelino Matarazzo, São Paulo, SP 03828-000 (Brazil)
  4. Universidade de São Paulo, Instituto de Astronomia, Geofísica e Cîenças Atmosféricas, Rua do Matão 1226, Butantã, São Paulo, SP 05508-900 (Brazil)
Publication Date:
OSTI Identifier:
22270595
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 777; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALFVEN WAVES; ASTRONOMY; ASTROPHYSICS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; COSMIC DUST; DEPOLARIZATION; INCLINATION; LIMITING VALUES; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; POLARIZATION; STARS; THREE-DIMENSIONAL CALCULATIONS; TURBULENCE; TWO-DIMENSIONAL CALCULATIONS; ZEEMAN EFFECT