A comparison between cold and thermal neutron prompt gamma activation analysis in the determination of carbon, nitrogen, and phosphorus in cattail

Methods for the determination of total carbon (TC), total nitrogen (TN), and total phosphorus (TP) in cattail (Typha domingensis) using cold and thermal neutron prompt gamma activation analysis (CNPGAA and TNPGAA) have been developed in the CNPGAA and TNPGAA facilities at the National Institute of Standards and Technology (NIST), and evaluated through the analysis of Standard Reference Materials (SRMs) in previous studies. There are major issues that impact the sensitivities of C, N and P using CNPGAA and TNPGAA including the effects of hydrogen content in samples, sample thickness and Compton scattering. However, interference from chlorine (Cl) in cattails has a major impact on the detection of P. This paper compares the effects of hydrogen content, sample thickness and Compton scattering on the sensitivities of C, N, and P between CNPGAA and TNPGAA and provides a resolution to the Cl interference on P in cattail.