ASTM E496

1.1 This test method covers a general procedure for the measurement of the fast-neutron fluence rate produced by neutron generators utilizing the ³H(d,n)⁴He reaction. Neutrons so produced are usually referred to as 14-MeV neutrons, but range in energy depending on a number of factors. This test method does not adequately cover fusion sources where the velocity of the plasma may be an important consideration.

1.2 This test method uses threshold activation reactions to determine the average energy of the neutrons and the neutron fluence at that energy. At least three activities, chosen from an appropriate set of dosimetry reactions, are required to characterize the average energy and fluence. The required activities are typically measured by gamma ray spectroscopy.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents

E170 Terminology Relating to Radiation Measurements and Dosimetry
E181 Test Methods for Detector Calibration and Analysis of Radionuclides
E261 Practice for Determining Neutron Fluence Rates, Fluence, and Spectra by Radioactivation Techniques
E265 Test Method for Measuring Reaction Rates and Fast-Neutron Fluences by Radioactivation of Sulfur-32
E720 Guide for Selection and Use of Neutron-Activation Foils for Determining Neutron Spectra Employed in Radiation-Hardness Testing of Electronics
Guide to the Expression of Uncertainty in Measurement
ICRU Report 13-Neutron Fluence, Neutron Spectra and Kerma
ICRU Report 26-Neutron Dosimetry for Biology and Medicine
Technical Note 1297-Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results

Index Terms

14-MeV; DT; neutron activation; neutron generator; neutron metrology; ICS Number Code 17.240; 27.120.30

Citing ASTM Standards

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