The angular and energy distributions of neutrons produced by 100 to 400 MeV/nucleon He, C, Ne, Ar, Fe, Xe ions and 800 MeV/nucleon Si ions stopping in thick C, Al, Cu and Pb targets were systematically measured using the Heavy Ion Medical Accelerator (HIMAC) of the National Institute of Radiological Sciences, Japan. The neutron spectra spread to almost twice as much as the projectile energy per nucleon, and were integrated over energy to produce neutron angular distributions. The total neutron yields obtained by integrating over the angular distributions could be fitted to a simple semi-empirical formula. The phenomenological hybrid analysis, based on the moving source model and the Gaussian fitting of the break-up and knock-on processes, could also well represent the measured thick target neutron spectra. This phenomenological analytical equation is expressed with several parameters as functions of atomic number Z_p, mass number A_p, energy per nucleon E_p for projectile, and atomic number Z_T, mass number A_T for target. This equation is quite useful for estimating the neutron source term in the neutron shielding design of high-energy heavy-ion accelerators.
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