Published March 1, 2020 | Version v1
Journal article

hammurabi X: Simulating Galactic Synchrotron Emission with Random Magnetic Fields

  • 1. Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, I-34136 Trieste (Italy)
  • 2. Department of Astronomy, University of Maryland, College Park, MD, 20742 (United States)
  • 3. Max Planck Institute for Astrophysics, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany)
  • 4. CAS Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Hefei 230026 (China)
  • 5. Center for Gravitation and Cosmology, College of Physical Science and Technology, Yangzhou University, Yangzhou 225009 (China)

Description

We present version X of the hammurabi package, the HEALPix-based numeric simulator for Galactic polarized emission. Improving on its earlier design, we have fully renewed the framework with modern C++ standards and features. Multithreading support has been built in to meet the growing computational workload in future research. For the first time, we present precision profiles of the hammurabi line-of-sight integral kernel with multilayer HEALPix shells. In addition to fundamental improvements, this report focuses on simulating polarized synchrotron emission with Gaussian random magnetic fields. Two fast methods are proposed for realizing divergence-free random magnetic fields either on the Galactic scale where field alignment and strength modulation are imposed, or on a local scale where more physically motivated models like a parameterized magnetohydrodynamic (MHD) turbulence can be applied. As an example application, we discuss the phenomenological implications of Gaussian random magnetic fields for high Galactic latitude synchrotron foregrounds. In this, we numerically find B/E polarization-mode ratios lower than unity based on Gaussian realizations of either MHD turbulent spectra or in spatially aligned magnetic fields.

Availability note (English)

Available from http://dx.doi.org/10.3847/1538-4365/ab72a2

Additional details

Identifiers

Publishing Information

Journal Title
Astrophysical Journal. Supplement Series
Journal Volume
247
Journal Issue
1
Journal Page Range
[19 p.]
ISSN
0067-0049
CODEN
APJSA2

INIS

Country of Publication
United Kingdom
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
52057346
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Descriptors DEI
EMISSION; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; POLARIZATION; SPECTRA; SYNCHROTRON RADIATION; TURBULENCE
Descriptors DEC
BREMSSTRAHLUNG; ELECTROMAGNETIC RADIATION; FLUID MECHANICS; HYDRODYNAMICS; MECHANICS; RADIATIONS