Neutrino astronomy with the MACRO detector

High-energy gamma-ray astronomy is now a well-established field, and severa l sources have been discovered in the region from a few giga-electron volts up to several tera-electron volts. If sources involving hadronic processes exist, the production of photons would be accompanied by neutrinos too. Ot her possible neutrino sources could be related to the annihilation of weakl y interacting, massive particles (WIMPs) at the center of galaxies with bla ck holes. We present the results of a search for pointlike sources using 11 00 upward-going muons produced by neutrino interactions in the rock below a nd inside the Monopole Astrophysics and Cosmic Ray Observatory (MACRO) dete ctor in the underground Gran Sasso Laboratory. These data show no evidence of a possible neutrino pointlike source or of possible correlations between gamma-ray bursts and neutrinos. They have been used to set flux upper limi ts for candidate pointlike sources which are in the range 10(-14)-10(-15) c m(-2) s(-1).