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We describe the beam characteristics of the first ballistic supermirror neutron guide H113 that feeds the neutron user facility for particle physics PF1B of the Institute Laue-Langevin, Grenoble (ILL). At present, the neutron capture flux density of H113 at its 20×6cm² exit window is Φ_C=1.35×10¹⁰cm^-2s^-1, and will soon be raised to above 2×10¹⁰cm⁻²s⁻¹. Beam divergence is no larger than beam divergence from a conventional Ni-coated guide. A model is developed that permits rapid calculation of beam profiles and absolute event rates from such a beam. We propose a procedure that permits inter-comparability of the main features of beams emitted from ballistic or conventional neutron guides.