A phenomenological profile of the Higgs boson

A discussion is given of the production, decay and observability of the scalar Higgs boson H expected in gauge theories of the weak and electromagnetic interactions such as the Weinberg-Salam model. After reviewing previous experimental limits on the mass of the Higgs boson, a speculative cosmological argument for a small mass is given. The reactions and decays in which a Higgs boson should occur, for various values of its mass, are described. If the Higgs boson has a mass <or=2 m/sub mu /, the decays H to e/sup +/e/sup -/ and H to gamma gamma dominate, and the lifetime is O(6*10/sup -4/ to 2*10/sup -12/) seconds. As thresholds for heavier particles (pions, strange particles, new particles) are crossed, decays into them become dominant, and the lifetime decreases rapidly to O(10/sup -20/) sec for a Higgs boson of mass 10 GeV. Decay branching ratios in principle enable the quark masses to be determined. (62 refs).