An irradiation is executed in a spallation neutron spectrum at the beam stop of LAMPF (Los Alamos). This neutron spectrum is much harder than a fission spectrum; a few percent of the neutrons have energies above 10 MeV and up to some hundreds of MeV. The irradiation took place from October 1982 to February 1983 and reached a fluence of 2.2 × 10¹⁹ n/cm². Temperature during irradiation was 120°C. The neutron spectrum is monitored by seven sets of monitor foils. From the foil activities the spectrum is deduced by unfolding codes. On some foils total He production measurements are executed. It is concluded that the spallation neutrons are accompanied by a few percent of high energy protons.