Instrumental Neutron Activation Analysis for Lunar Samples Returned by Chang'E-5

Abstract

New lunar samples retrieved by Chang’E-5 mission were collected from the lunar mid-latitudes (51.916°W, 43.058°N) in the northwest region of Oceanus Procellarum where human beings have never yet been explored, made up for the limited sampling area visited by the United States and the former Soviet Union more than 40 years ago. The Chang’E-5 samples expanded the representation of lunar samples and have extremely important value for scientific research. The concentration values of 39 elements for the Chang’E-5 samples shoveled up from the moon surface were obtained by instrumental neutron activation analysis (INAA), which has the inherent advantages of high sensitivity, multi-elemental and non-destructive analysis, etc. The neutron irradiation experiments of Chang’E-5 samples were carried out in the 49-2 Swimming Pool Reactor (SPR) and Miniature Neutron Source Reactor (MNSR) at China Institute of Atomic Energy (CIAE) for long-time and short-time INAA, respectively. And a hybrid k0-relative method software ADVNAA homemade-in NAA lab of CIAE was used for elemental quantitative analysis of the Chang’E-5 lunar samples. The analysis data obtained were compared with the elemental composition of Apollo-17 sample which was a national gift from the United States to China in 1978. In order to ensure the accuracy and reliability of the analysis of the Chang’E-5 lunar soil samples, some certified reference materials were used such as GBW07105, GBW07727, GBW07896, SRM2703, GSP2, etc. The results showed that the measured values of the quality control reference materials and the certified values were in agreement within the uncertainty range.

Keywords

• chang’e-5
• neutron activation analysis
• lunar soil samples