Probing the deuteron breakup and linking the cross sections of residue production between the neutron- and deuteron-induced spallation at 500 MeV/nucleon

Background: Cross section data of neutron-induced spallation are requisite in order to study the transmutation of the long-lived fission products from the spallation. However, those data are very scarce at present due to the difficulty of providing a neutron source in the GeV region and the impossibility of the inverse dynamics. Purpose: The present work is an attempt to probe the dynamic process of deuteron breakup in deuteron-induced spallation and discuss the possibility of measuring indirectly the cross section in neutron-induced spallation. Method: The isospin-dependent quantum molecular dynamics model is applied to simulate the spallation process until the excitation energy of the hot fragment is less than 2 MeV/nucleon. The statistical model GEMINI based on the Hauser-Feshbach formalism is used to describe the deexcitation of the hot fragments. Results: By comparing the calculations to the data, the theoretical framework is proved to be reasonable when predicting the neutron production in spallation. By investigating the deuteron breakup, deuteron-induced spallation is divided into deuteron absorbing, neutron stripping, proton stripping, and elastic breakup. It is found that the proton stripping plays the dominant role in the production of high-energy neutrons, while the neutron stripping is responsible for the emission of high-energy protons. Due to the weak binding of the deuteron, it is suggested that the combination of neutron stripping and elastic breakup in deuteron-induced spallation is equivalent to neutron-induced spallation. Conclusions: Using the proton recoiling from the deuteron as the trigger signal, deuteron-induced spallation may be applied to measure indirectly the cross section in neutron-induced spallation.