ON THE MICROWAVE BACKGROUND ANISOTROPY PRODUCED BY GREAT ATTRACTOR-LIKE STRUCTURES

We model the effect on the cosmic microwave background of Great Attrac tor-like structures located at various distances from us. These struct ures are described by using the Tolman-Bondi solution of the Einstein equations. Two values of the density parameter, OMEGA0 = 0.2 and OMEGA 0 = 1, are considered. Physical initial profiles of the energy density and the peculiar velocity lead to both compensated and uncompensated models. Nonlinear gauge-invariant computations give the angular distri bution of the microwave background temperature. Angular sizes, amplitu des, and angular temperature profiles of various separable contributio ns to the total anisotropy are estimated and compared among them. Thes e contributions are produced by the gravitational field, the peculiar velocities of the observer and the emitter, and the temperature fluctu ations on the last scattering surface induced by Great Attractor-like structures. Compatibility with observational evidence is analyzed. It is proved that the greatest anisotropies are produced by Great Attract or-like objects located near the last scattering surface. Suitable ang ular scales for the future detection of these anisotropies are propose d. For fixed proportions of baryon and dark matter, results strongly d epend on the value of the density parameter OMEGA0; the smallest aniso tropies correspond to OMEGA0 = 1.