Radio continuum observations detect non-thermal synchrotron and thermal bremsstrahlung radiation. Separation of the two different emission components is crucial to study the properties of diffuse interstellar medium. The Cygnus X region is one of the
most complex areas in the radio sky which contains a number of massive stars and HII regions on the diffuse thermal and non-thermal background. More supernova remnants are expected to be discovered. We aim to develop a method which can properly separate the non-thermal and thermal radio continuum emission and apply it to the Cygnus X region. The result can be used to study the properties of different emission components and search for new supernova remnants in the complex. Multi-frequency radio continuum data from large-scale surveys are used to develop a new component separation method. Spectral analysis is done pixel by pixel for the non-thermal synchrotron emission with a realistic spectral index distribution and a fixed spectral index of beta = -2.1 for the thermal bremsstrahlung emission. With the new method, we separate the non-thermal and thermal components of the Cygnus X region at an angular resolution of 9.5arcmin. The thermal emission component is found to comprise 75% of the total continuum emission at 6cm. Thermal diffuse emission, rather than the discrete HII regions, is found to be the major contributor to the entire thermal budget. A smooth non-thermal emission background of 100 mK Tb is found. We successfully make the large-extent known supernova remnants and the HII regions embedded in the complex standing out, but no new large SNRs brighter than Sigma_1GHz = 3.7 x 10^-21 W m^-2 Hz^-1 sr^-1 are found.
Linearly polarized Galactic synchrotron emission provides valuable information about the properties of the Galactic magnetic field and the interstellar magneto-ionic medium, when Faraday rotation along the line of sight is properly taken into account
. We aim to survey the Galactic plane at 6 cm including linear polarization. At such a short wavelength Faraday rotation effects are in general small and the Galactic magnetic field properties can be probed to larger distances than at long wavelengths. The Urumqi 25-m telescope is used for a sensitive 6 cm survey in total and polarized intensities. WMAP K-band (22.8 GHz) polarization data are used to restore the absolute zero-level of the Urumqi U and Q maps by extrapolation. Total intensity and polarization maps are presented for a Galactic plane region of 129 degree < l < 230 degree and |b| < 5 degree in the anti-centre with an angular resolution of 95 and an average sensitivity of 0.6 mK and 0.4 mK Tb in total and polarized intensity, respectively. We briefly discuss the properties of some extended Faraday Screens detected in the 6 cm polarization maps. The Sino-German 6 cm polarization survey provides new information about the properties of the magnetic ISM. The survey also adds valuable information for discrete Galactic objects and is in particular suited to detect extended Faraday Screens with large rotation measures hosting strong regular magnetic fields.
