Characterization of the polarized synchrotron emission from Planck and WMAP data

Abstract

The purpose of this work is to characterize the diffuse Galactic polarized synchrotron, which is the dominant CMB foreground emission at low frequency. We present EE, BB, and EB power spectra estimated from polarization frequency maps at 23 and 30 GHz as observed respectively by the WMAP K-band and the Planck lowest frequency channel, for a set of six sky regions covering from 30% to 94% of the sky. We study the synchrotron polarization angular distribution and spectral energy distribution (SED) by means of the so-called pseudo-$C_{\ell }$ formalism, provided by the NaMaster package, in the multipole interval 30 $\le$ $\ell$ $\le$ 300. Best results are obtained cross-correlating Planck and WMAP data. The EE and BB angular power spectra show a steep decay of the spectral amplitude as a function of multipole, approximated by a power law $C^{EE,BB}\propto {\ell }^{{\alpha }_{EE,BB}}$, with ${\alpha }_{EE}=-2.95\pm 0.04$ and ${\alpha }_{BB}=-2.85\pm 0.14$. The B/E power asymmetry is proved with a B-to-E ratio, computed as the amplitude ratio at the pivot multipole $\ell =80$, of 0.22$\pm$0.02. The EB cross-component is compatible with zero at 1$\sigma$, with an upper constraint on the EB/EE ratio of 1.2% at the 2$\sigma$ level. We show that the EE and BB power-law model with null EB cross-correlation describes reasonably well the diffuse synchrotron polarization emission for the full sky if the bright Galactic center and point sources are masked. The recovered SED shows power-law spectral indices ${\beta }_{EE}=-3.00\pm 0.10$ and ${\beta }_{BB}=-3.05\pm 0.36$ compatible between themselves, in the frequency range 23-30 GHz. Results also seem to indicate that the SED gets steeper from low to high Galactic latitude.

References in corpus (34)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Final Maps and Results
• Planck 2018 results. I. Overview and the cosmological legacy of Planck
• A Joint Analysis of BICEP2/Keck Array and Planck Data
• Planck 2018 results. VII. Isotropy and Statistics of the CMB
• CMB Anisotropies: Total Angular Momentum Method
• Planck 2018 results. IV. Diffuse component separation
• A unified pseudo-$C_{\ell }$ framework
• Planck 2018 results. III. High Frequency Instrument data processing and frequency maps
• Planck intermediate results. LVII. Joint Planck LFI and HFI data processing
• Component separation methods for the Planck mission
• The Python Sky Model: software for simulating the Galactic microwave sky
• Acoustic Signatures in the Cosmic Microwave Background
• Planck intermediate results. XXX. The angular power spectrum of polarized dust emission at intermediate and high Galactic latitudes
• Separation of anomalous and synchrotron emissions using WMAP polarization data
• Planck 2018 results. XI. Polarized dust foregrounds
• A determination of the Spectra of Galactic components observed by WMAP
• The State-of-Play of Anomalous Microwave Emission (AME) Research
• CMB polarization as a direct test of Inflation
• The S-PASS view of polarized Galactic Synchrotron at 2.3 GHz as a contaminant to CMB observations
• S-band Polarization All Sky Survey (S-PASS): survey description and maps
• Comparison of filters for the detection of point sources in Planck simulations
• QUIJOTE Scientific Results. II. Polarisation Measurements of the Microwave Emission in the Galactic molecular complexes W43 and W47 and supernova remnant W44
• A New Test of Inflation
• A minimal power-spectrum-based moment expansion for CMB B-mode searches
• Determination of miscalibrated polarization angles from observed CMB and foreground $EB$ power spectra: Application to partial-sky observation
• Polarization of the WMAP Point Sources
• Constraints on the spectral index of polarized synchrotron emission from WMAP and Faraday-corrected S-PASS data
• Detection/estimation of the modulus of a vector. Application to point source detection in polarization data
• Sufficiency of a Gaussian power spectrum likelihood for accurate cosmology from upcoming weak lensing surveys
• ECLIPSE: a fast Quadratic Maximum Likelihood estimator for CMB intensity and polarization power spectra
• The C-Band All-Sky Survey (C-BASS): Digital backend for the northern survey

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• Polarized Synchrotron Foreground Assessment for CMB Experiments
• Morphological Analysis of the Polarized Synchrotron Emission with WMAP and Planck
• Modeling parity-violating spectra in Galactic dust polarization with filaments and its applications to cosmic birefringence searches
• Testing for spectral index variations in polarised CMB foregrounds
• eROSITA X-ray Analysis of the PeVatron Candidate Westerlund 1
• Cosmoglobe DR1. III. First full-sky model of polarized synchrotron emission from all WMAP and Planck LFI data
• Statistical properties of Galactic synchrotron temperature and polarization maps -- a multi-frequency comparison
• Forecasts of constraining isotropic cosmic birefringence on AliCPT-1