We demonstrated that (n, 2n) and (n, gamma) reactions are induced by a high-flux pulse of fast neutrons provided from a Laser-driven Neutron Source (LDNS). The maximum energy of the broadband neutrons reaches a few tens MeV. Several kinds of metal targets are exposed to the fast neutrons. As a result, unstable isotopes such as 54Mn, 58Co, 175Hf, and 196Au are produced by (n, 2n) reactions and 180Hfm,181Hf, 56Mn, 198Au, and 60Co are produced by (n, gamma) reactions. We evaluate the neutron fluence and energy spectrum using the activation method in conjunction with a time-of-flight (TOF) method. The present scheme provides a method to evaluate high density neutrons seen in stellar environments, which are expected to be generated from future LDNSs
