Constraining models of the large scale Galactic magnetic field with WMAP5 polarization data and extragalactic Rotation Measure sources

Abstract

We introduce a method to quantify the quality-of-fit between data and observables depending on the large scale Galactic magnetic field. We combine WMAP5 polarized synchrotron data and Rotation Measures of extragalactic sources in a joint analysis to obtain best fit parameters and confidence levels for GMF models common in the literature. None of the existing models provide a good fit in both the disk and halo regions, and in many instances best-fit parameters are quite different than the original values. We note that probing a very large parameter space is necessary to avoid false likelihood maxima. The thermal and relativistic electron densities are critical for determining the GMF from the observables but they are not well constrained. We show that some characteristics of the electron densities can already be constrained using our method and with future data it may be possible to carry out a self-consistent analysis in which models of the GMF and electron densities are simultaneously optimized.

27 pages, 13 figures. Accepted for publication in JCAP; arXiv version updated to include minor revisions

References in corpus (28)

• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• Three Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Polarization Analysis
• Cosmic-ray propagation and interactions in the Galaxy
• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Parameter Estimation Methodology
• NE2001.I. A New Model for the Galactic Distribution of Free Electrons and its Fluctuations
• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Galactic Foreground Emission
• Radio observational constraints on Galactic 3D-emission models
• Pulsar rotation measures and the large-scale structure of Galactic magnetic field
• The Vertical Structure of Warm Ionised Gas in the Milky Way
• Separation of anomalous and synchrotron emissions using WMAP polarization data
• Rotation Measures of Extragalactic Sources Behind the Southern Galactic Plane: New Insights into the Large-Scale Magnetic Field of the Inner Milky Way
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Galactic Foreground Emission
• Ultra high energy cosmic rays and the large scale structure of the galactic magnetic field
• An absolutely calibrated survey of polarized emission from the northern sky at 1.4 GHz
• Radio polarization from the inner Galaxy at arcminute resolution
• A New Model For The Loop-I (The North Polar Spur) Region
• Simulating polarized Galactic synchrotron emission at all frequencies, the Hammurabi code
• The Origin and Evolution of Cosmic Magnetism
• Tracing protons through the Galactic magnetic field: a clue for charge composition of ultra-high energy cosmic rays
• The toes of the ultra high energy cosmic ray spectrum
• The Galactic magnetic field and propagation of ultra-high energy cosmic rays
• The effect of HII regions on rotation measure of pulsars
• Milestones in the Observations of Cosmic Magnetic Fields
• The Galactic magnetic field as spectrograph for ultra-high energy cosmic rays
• NE2001. II. Using Radio Propagation Data to Construct a Model for the Galactic Distribution of Free Electrons
• Galactic and Extragalactic Magnetic Fields
• Cosmic Magnetism with the Square Kilometre Array and its Pathfinders

Cited by in corpus (53)

• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Cosmological Magnetic Fields: Their Generation, Evolution and Observation
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• Deriving global structure of the Galactic Magnetic Field from Faraday Rotation Measures of extragalactic sources
• New limits on dark matter annihilation from AMS cosmic ray positron data
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• The pre-launch Planck Sky Model: a model of sky emission at submillimetre to centimetre wavelengths
• Sensitivity of gamma-ray telescopes for detection of magnetic fields in intergalactic medium
• Galactic electrons and positrons at the Earth:new estimate of the primary and secondary fluxes
• Hardening of TeV gamma spectrum of AGNs in galaxy clusters by conversions of photons into axion-like particles
• Modelling the Galactic Magnetic Field on the Plane in 2D
• The Galactic halo magnetic field revisited
• Radio Continuum Surveys with Square Kilometre Array Pathfinders
• Cosmic Ray Anisotropy as Signature for the Transition from Galactic to Extragalactic Cosmic Rays
• Magnetic Fields in the Milky Way
• The Coherent Magnetic Field of the Milky Way
• New constraints on modelling the random magnetic field of the MW
• On the Distance of SGR 1935+2154 Associated with FRB 200428 and Hosted in SNR G57.2+0.8
• A radio-polarisation and rotation measure study of the Gum Nebula and its environment
• Cosmic ray spectrum in the local Galaxy
• Ultrahigh Energy Nuclei in the Turbulent Galactic Magnetic Field
• Analytical models of X-shape magnetic fields in galactic halos
• Comparing Polarised Synchrotron and Thermal Dust Emission in the Galactic Plane
• Joint 3D modelling of the polarized Galactic synchrotron and thermal dust foreground diffuse emission
• Galactic synchrotron emission from WIMPs at radio frequencies
• Galactic Center Radio Constraints on Gamma-Ray Lines from Dark Matter Annihilation
• The Fermi Gamma-Ray Haze from Dark Matter Annihilations and Anisotropic Diffusion
• Importance of axion-like particles for very-high-energy astrophysics
• Ultrahigh Energy Nuclei in the Galactic Magnetic Field
• Probing magnetic helicity with synchrotron radiation and Faraday rotation
• Remarkable symmetries in the Milky Way disk's magnetic field
• A Model For Polarised Microwave Foreground Emission From Interstellar Dust
• The Complex Large-scale Magnetic Fields in the First Galactic Quadrant as Revealed by the Faraday Depth Profile Disparity
• Galactic magnetic fields and the large-scale anisotropy at MILAGRO
• Constraining the regular Galactic Magnetic Field with the 5-year WMAP polarization measurements at 22 GHz
• Efficiency of Thermal Conduction in a Magnetised Circumgalactic Medium
• Diffuse Galactic Gamma Rays at intermediate and high latitudes. I. Constraints on the ISM properties
• Faraday caustics: Singularities in the Faraday spectrum and their utility as probes of magnetic field properties
• CRT: A numerical tool for propagating ultra-high energy cosmic rays through Galactic magnetic field models
• Late decaying 2-component dark matter scenario as an explanation of the AMS-02 positron excess
• The Parkes Galactic Meridian Survey (PGMS): observations and CMB polarization foreground analysis
• The coherent magnetic field of the Milky Way halo, Local Bubble and Fan Region
• The Galaxy in circular polarization: all-sky radio prediction, detection strategy, and the charge of the leptonic cosmic rays
• Search for single sources of ultra high energy cosmic rays on the sky
• Expected constraints on the Galactic magnetic field using PLANCK data
• Method to Look for Imprints of Ultrahigh Energy Nuclei Sources
• MiXDM: Cosmic Ray Signals from Multiple States of Dark Matter
• Model of the polarized foreground diffuse Galactic emissions from 33 to 353 GHz
• Influence of Magnetic Fields on the Gas Rotation in the Galaxy $NGC6946$
• A Method for Constraining Cosmic Magnetic Field Models Using Ultra-High Energy Cosmic Rays: The Field Scan Method
• HERMES: Simulating the Propagation of Ultra-High Energy Cosmic Rays
• A lower bound on the number of cosmic ray events required to measure source catalogue correlations