EXPERIMENTAL SEARCH FOR A NEW LIGHT BARYON

A search was conducted for a light baryon X++ in the mass range M(N) M(pi) greater-than-or-equal-to M(X) greater-than-or-equal-to M(N), by bombarding a CH2 target with 460 MeV protons, and detecting the produ cts in the Medium Resolution Spectrometer, which was placed at a scatt ering angle of 15 degrees. No doubly charged baryon in this mass range was detected, thus setting an upper limit of a few tens pb/sr for the reaction. The experiment indicates that if such a light baryon exists its interaction with the ''ordinary'' physical world is very weak, pr obably at least 10(7) times weaker than the strong interaction.