Speaker
Description
We present a self-contained re-analysis of the five frequency-band all sky observations from the Wilkinson Microwave Anisotropy Probe (WMAP) to investigate in detail the characteristics of Galactic synchrotron emission. The K, Ka, Q, V and W maps are homogenised in angular resolution and pixelisation, and are converted from thermodynamic temperature units to Rayleigh-Jeans (antenna) temperature, a transformation essential for modelling Galactic foregrounds that follow power-law spectra. Using fixed spectral indices for synchrotron, free-free and thermal dust emission, together with a frequency-independent CMB component, we perform pixel-by-pixel least-squares fitting to separate the principal microwave sky emissions without the use of external templates. An optional internal linear combination (ILC) stage is implemented to suppress CMB anisotropies prior to foreground fitting.
From the resulting component maps we extract the synchrotron amplitude at a reference frequency and analyse its variation with Galactic longitude and latitude, quantifying its distribution both along the Galactic plane and at high latitudes. Our procedure yields refined constraints on the morphology, spectral behaviour and large-scale structure of the Milky Way’s synchrotron emission, thereby providing new insight into the relativistic electron population and the Galactic magnetic field.
| Stream | Science or Engineering |
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