Simulating polarized Galactic synchrotron emission at all frequencies, the Hammurabi code

We present a publicly available code called Hammurabi for generating mock polarized observations of Galactic synchrotron emission for telescopes like LOFAR, SKA, Planck and WMAP, based on model inputs for the Galactic magnetic field (GMF), the cosmic-ray density distribution and the thermal electron density. We also present mock UHECR deflection measure (UDM) maps based on model inputs for the GMF. In future, when UHECR sources are identified, this will allow us to define UDM as a GMF probe in a similar way as polarized radio sources permit us to define rotation measures. To demonstrate the codes abilities mock observations are compared to real data as a means to constrain the input parameters of our simulations with a focus on large-scale magnetic field properties. As expected, attempts at trying to model the synchrotron, UHECR deflection and RM input parameters, show that any additional observational data set greatly increases the constraints on the models. The hammurabi code addresses this by allowing to perform simulations of several different data sets simultaneously, providing the means for a more reliable constraint of the magnetized inter-stellar-medium.

Camouflaged galactic CMB foregrounds: total and polarized contributions of the kinetic Sunyaev Zeldovich effect

We consider the role of the galactic kinetic Sunyaev Zeldovich (SZ) effect as a CMB foreground. While the galactic thermal Sunyaev Zeldovich effect has previously been studied and discarded as a potential CMB foreground, we find that the kinetic SZ effect is dominant in the galactic case. We analyse the detectability of the kinetic SZ effect by means of an optimally matched filter technique applied to a simulation of an ideal observation. We obtain no detection, getting a S/N ratio of 0.1, thereby demonstrating that the kinetic SZ effect can also safely be ignored as a CMB foreground. However we provide maps of the expected signal for inclusion in future high precision data processing. Furthermore, we rule out the significant contamination of the polarised CMB signal by second scattering of galactic kinetic Sunyaev-Zeldovich photons, since we show that the scattering of the CMB quadrupole photons by galactic electrons is a stronger effect than the Sunyaev Zeldovich second scattering, and has already been shown to produce no significant polarised contamination. We confirm the latter assessment also by means of an optimally matched filter.