Search for neutrinos from the Sun and the Earth with the MACRO detector

Upward-going muon events collected with the lower half of the MACRO detector have been analyzed in order to search for Weakly Interacting Massive Particles possibly trapped in the core of the Sun and of the Earth. No statistically significant signal could be discriminated over the possible fluctuations of the atmosphere neutrino background. Assuming a particular neutralino model, the explorable neutralino mass region has been considered. (orig.)