ASTM E944-13
Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance, E???706 (IIA)

Standard No.

ASTM E944-13

Release Date

2013

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM E944-13e1

Latest

ASTM E944-19

Scope

3.1 Adjustment methods provide a means for combining the results of neutron transport calculations with neutron dosimetry measurements (see Test Method E1005 and NUREG/CR-5049) in order to obtain optimal estimates for neutron damage exposure parameters with assigned uncertainties. The inclusion of measurements reduces the uncertainties for these parameter values and provides a test for the consistency between measurements and calculations and between different measurements (see 3.3.3). This does not, however, imply that the standards for measurements and calculations of the input data can be lowered; the results of any adjustment procedure can be only as reliable as are the input data.

3.2 Input Data and Definitions :

3.2.1 The symbols introduced in this section will be used throughout the guide.

3.2.2 Dosimetry measurements are given as a set of reaction rates (or equivalent) denoted by the following symbols:

These data are, at present, obtained primarily from radiometric dosimeters, but other types of sensors may be included (see 4.1).

3.2.3 The neutron spectrum (see Terminology E170) at the dosimeter location, fluence or fluence rate Φ(E) as a function of neutron energy E , is obtained by appropriate neutronics calculations (neutron transport using the methods of discrete ordinates or Monte Carlo, see Guide E482). The results of the calculation are customarily given in the form of multigroup fluences or fluence rates.

where:
E_j and E_j+1 are the lower and upper bounds for the j-th energy group, respectively, and k is the total number of groups.

3.2.4 The reaction cross sections of the dosimetry sensors are obtained from an evaluated cross section file. The cross section for the i-th reaction as a function of energy E will be denoted by the following:

ASTM E944-13 history

• 2019 ASTM E944-19 Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance
• 2013 ASTM E944-13e1 Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance
• 2013 ASTM E944-13 Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance, E???706 (IIA)
• 2008 ASTM E944-08 Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance, E706 (IIA)
• 2002 ASTM E944-02 Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance, E706 (IIA)
• 1996 ASTM E944-96 Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance, (IIA)