A Search for Dust Clouds near the Solar System with the Wilkinson Microwave Anisotropy Probe

点击翻译按钮获取中文摘要

The Wilkinson Microwave Anisotropy Probe (WMAP) has built a map of the celestial sphere at millimetre wavelengths. Designed to characterize the fluctuations of the cosmic microwave background (CMB) radiation, WMAP is also sensitive to many foreground sources, e.g. the thermal emission from cosmic dust. Dedicated models were constructed to remove the emission by galactic dust from the observations. Some other foregrounds, however, may have stayed unaccounted. Moreover, the WMAP data suggest that an unaccounted bias is likely, revealed by the low power and suspicious alignment mutually and with the solar-system geometry of the quadrupole and octopole moments of the multipole expansion of the CMB fluctuations. Thus the goal of the proposed project is to search the WMAP data for local sources of microwave radiation and to put constraints on dust clouds in the vicinity of the Solar system in a new wavelength range. The project might also help to resolve the mysterious alignment of the low-order multipoles, and thus have important cosmological repercussions.