ASTM-E264 2008(Redline)

$23.40

E264-08 Standard Test Method for Measuring Fast-Neutron Reaction Rates by Radioactivation of Nickel (Redline)

Published By	Publication Date	Number of Pages
ASTM	2008	4

Guaranteed Safe Checkout

Categories: 27.120.30 - Fissile materials and nuclear fuel technology, ASTM

If you have any questions, feel free to reach out to our online customer service team by clicking on the bottom right corner. We’re here to assist you 24/7.
Email:[email protected]

Description

Significance and Use

Refer to Guide E 844 for the selection, irradiation, and quality control of neutron dosimeters.

Refer to Practice E 261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors.

Pure nickel in the form of foil or wire is readily available, and easily handled.

⁵⁸ Co has a half-life of 70.86 days and emits a gamma ray with an energy of 0.8107593-MeV.

Competing activities ⁶⁵ Ni(2.5172 h) and ⁵⁷ Ni(35.60 h) are formed by the reactions ⁶⁴ Ni(n, γ ) ⁶⁵ Ni, and ⁵⁸ Ni(n,2n) ⁵⁷ Ni, respectively.

A second 9.04 h isomer, ^58m Co, is formed that decays to 70.86-day ⁵⁸ Co. Loss of ⁵⁸ Co and ^58m Co by thermal-neutron burnout will occur in environments ^, having thermal fluence rates of 3 × 10 ¹² cm ^{− 2} · s ^{− 1} and above. Burnout correction factors, R , are plotted as a function of time for several thermal fluxes in Fig. 1. Tabulated values for a continuous irradiation time are provided in Hogg, et al.

Fig. 2 shows a plot of cross section versus energy for the fast-neutron reaction ⁵⁸ Ni(n,p) ⁵⁸ Co. This figure is for illustrative purposes only to indicate the range of response of the ⁵⁸ Ni(n,p) reaction. Refer to Guide E 1018 for descriptions of recommended tabulated dosimetry cross sections.

Note 1—The data is taken from the Evaluated Nuclear Data File, ENDF/B-VI, rather than the later ENDF/B-VII. This is in accordance with E 1018, section 6.1, since the later ENDF/B-VII data files do not include covariance information. For more details see Section H of reference 8.

FIG. 2 ⁵⁸ Ni(n,p) ⁵⁸ Co Cross Section

1. Scope

1.1 This test method covers procedures for measuring reaction rates by the activation reaction ⁵⁸ Ni(n,p) ⁵⁸ Co.

1.2 This activation reaction is useful for measuring neutrons with energies above approximately 2.1 MeV and for irradiation times up to about 200 days in the absence of high thermal neutron fluence rates (for longer irradiations, see Practice E 261).

1.3 With suitable techniques fission-neutron fluence rates densities above 10 ⁷ cm ^{− 2} · s ^{− 1} can be determined.

1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E 261.

1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.6 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.

Note —The burnup corrections were computed using effective burn-up cross sections of 1650 b for ⁵⁸ Co(n, γ ) and 1.4E5 b for ^58m Co(n, γ ).

FIG. 1 R Correction Values as a Function of Irradiation Time and Neutron Flux

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

E170 Terminology Relating to Radiation Measurements and Dosimetry E181 Test Methods for Detector Calibration and Analysis of Radionuclides E261 Practice for Determining Neutron Fluence, Fluence Rate, and Spectra by Radioactivation Techniques E844 Guide for Sensor Set Design and Irradiation for Reactor Surveillance, E 706 (IIC) E944 Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance, E 706 (IIA) E1005 Test Method for Application and Analysis of Radiometric Monitors for Reactor Vessel Surveillance, E 706 (IIIA) E1018 Guide for Application of ASTM Evaluated Cross Section Data File, Matrix E706 (IIB)

Keywords

activation; activation reaction; cross section; dosimetry; fast-neutron monitor; neutron metrology; nickel; pressure vessel surveillance; reaction rate; Fast neutron flux/fluence; Neutron activation reactions; Nickel; Nickel alloys; Radioactivation–fast neutron flux; Threshold detectors–1 MeV;

ICS Code

ICS Number Code 17.240 (Radiation measurements); 27.120.30 (Fissile materials and nuclear fuel technology)

DOI: 10.1520/E0264-08

Additional information

Standard Title	E264-08 Standard Test Method for Measuring Fast-Neutron Reaction Rates by Radioactivation of Nickel (Redline)
Published Code	ASTM
Publication Date	2008
Pages Count	4
ICS Codes	27.120.30 - Fissile materials and nuclear fuel technology

Preview PDF


PDF Format	Searchable	Printable	Preview Now

ASTM-E264 2008(Redline)

Related products