ASTM E705-08

Standard Test Method for Measuring Reaction Rates by Radioactivation of Neptunium-237

SIGNIFICANCE AND USE
Refer to Practice E 261 for a general discussion of the determination of fast-neutron fluence rate with fission detectors.
237Np is available as metal foil, wire, or oxide powder. For further information, see Guide E 844. It is usually encapsulated in a suitable container to prevent loss of, and contamination by, the 237Np and its fission products.  
One or more fission products can be assayed. Pertinent data for relevant fission products are given in Table 1 and Table 2.
137Cs-137mBa is chosen frequently for long irradiations. Radioactive products 134Cs and 136Cs may be present, which can interfere with the counting of the 0.662 MeV 137Cs-137mBa gamma ray (see Test Methods E 320).
140Ba-140La is chosen frequently for short irradiations (see Test Method E 393).
95Zr can be counted directly, following chemical separation, or with its daughter 95Nb, using a high-resolution gamma detector system.
144Ce is a high-yield fission product applicable to 2- to 3-year irradiations.
It is necessary to surround the 237Np monitor with a thermal neutron absorber to minimize fission product production from trace quantities of fissionable nuclides in the 237Np target and from 238Np and 238Pu from (n,γ) reactions in the 237Np material. Assay of 238Pu and 239Pu concentration is recommended when a significant contribution is expected.
Fission product production in a light-water reactor by neutron activation products 238Np and 238Pu has been calculated to be insignificant (1.2 %), compared to that from 237Np(n,f), for an irradiation period of 12 years at a fast neutron (E > 1 MeV) fluence rate of 1 × 1011 cm−2·s−1, provided the 237Np is shielded from thermal neutrons (see Fig. 2 of Guide E 844).
Fission product production from photonuclear reactions, that is, (γ,f) reactions, while negligible near-power and researchreactor cores, can be large for deep-water penetrations (1).  
Good agreement between neutron fluence measured by 237Np fission and the 54Fe(n,p)54Mn reacti...
SCOPE
1.1 This test method covers procedures for measuring reaction rates by assaying a fission product (F.P.) from the fission reaction 237Np(n,f)F.P.
1.2 The reaction is useful for measuring neutrons with energies from approximately 0.7 to 6 MeV and for irradiation times up to 30 to 40 years.
1.3 Equivalent fission neutron fluence rates as defined in Practice E 261 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.

General Information

• Status: Historical
• Publication Date: 30-Jun-2008
• ICS: 17.240 - Radiation measurements
• ICS: 27.120.30 - Fissile materials and nuclear fuel technology
• Technical Committee: E10 - Nuclear Technology and Applications
• Drafting Committee: E10.05 - Nuclear Radiation Metrology

Relations

• Replaces: ASTM E705-96(2002) - Standard Test Method for Measuring Reaction Rates by Radioactivation of Neptunium-237
• Effective Date: 01-Jul-2008
• Replaced By: ASTM E705-13 - Standard Test Method for Measuring Reaction Rates by Radioactivation of Neptunium-237
• Effective Date: 01-Jun-2013
• Referred By: ASTM E720-23 - Standard Guide for Selection and Use of Neutron Sensors for Determining Neutron Spectra Employed in Radiation-Hardness Testing of Electronics
• Effective Date: 01-Jul-2008
• Referred By: ASTM E704-19 - Standard Test Method for Measuring Reaction Rates by Radioactivation of Uranium-238
• Effective Date: 01-Jul-2008
• Referred By: ASTM E944-19 - Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance
• Effective Date: 01-Jul-2008
• Referred By: ASTM E721-22 - Standard Guide for Determining Neutron Energy Spectra from Neutron Sensors for Radiation-Hardness Testing of Electronics
• Effective Date: 01-Jul-2008
• Referred By: ASTM E2005-21 - Standard Guide for Benchmark Testing of Reactor Dosimetry in Standard and Reference Neutron Fields
• Effective Date: 01-Jul-2008
• Referred By: ASTM E261-16(2021) - Standard Practice for Determining Neutron Fluence, Fluence Rate, and Spectra by Radioactivation Techniques
• Effective Date: 01-Jul-2008
• Referred By: ASTM E1854-19 - Standard Practice for Ensuring Test Consistency in Neutron-Induced Displacement Damage of Electronic Parts
• Effective Date: 01-Jul-2008
• Referred By: ASTM E393-19 - Standard Test Method for Measuring Reaction Rates by Analysis of Barium-140 From Fission Dosimeters
• Effective Date: 01-Jul-2008
• Referred By: ASTM E1005-21 - Standard Test Method for Application and Analysis of Radiometric Monitors for Reactor Vessel Surveillance
• Effective Date: 01-Jul-2008

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E705 − 08
StandardTest Method for
Measuring Reaction Rates by Radioactivation of Neptunium-
1
237
This standard is issued under the fixed designation E705; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E320TestMethodforCesium-137inNuclearFuelSolutions
3
by Radiochemical Analysis (Withdrawn 1993)
1.1 This test method covers procedures for measuring reac-
E393Test Method for Measuring Reaction Rates byAnaly-
tion rates by assaying a fission product (F.P.) from the fission
237 sis of Barium-140 From Fission Dosimeters
reaction Np(n,f)F.P.
E704Test Method for Measuring Reaction Rates by Radio-
1.2 The reaction is useful for measuring neutrons with
activation of Uranium-238
energies from approximately 0.7 to 6 MeV and for irradiation
E844Guide for Sensor Set Design and Irradiation for
times up to 30 to 40 years.
Reactor Surveillance, E 706 (IIC)
1.3 Equivalent fission neutron fluence rates as defined in E944Guide for Application of Neutron Spectrum Adjust-
ment Methods in Reactor Surveillance, E 706 (IIA)
Practice E261 can be determined.
E1005Test Method for Application and Analysis of Radio-
1.4 Detailed procedures for other fast-neutron detectors are
metric Monitors for Reactor Vessel Surveillance, E 706
referenced in Practice E261.
(IIIA)
1.5 The values stated in SI units are to be regarded as
E1018Guide for Application of ASTM Evaluated Cross
standard. No other units of measurement are included in this
Section Data File, Matrix E706 (IIB)
standard.
1.6 This standard does not purport to address all of the 3. Terminology
safety concerns, if any, associated with its use. It is the
3.1 Definitions:
responsibility of the user of this standard to establish appro-
3.1.1 Refer to Terminology E170.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
4. Summary of Test Method
237
2. Referenced Documents
4.1 High-purity Np (<40 ppm fissionable impurity) is
2
irradiatedinafast-neutronfield,therebyproducingradioactive
2.1 ASTM Standards:
237
fission products from the reaction Np(n,f)F.P.
E170Terminology Relating to Radiation Measurements and
137 137m 1140
Dosimetry
4.2 Various fission products such as Cs- Ba, Ba-
140 95 144
E181Test Methods for Detector Calibration andAnalysis of
La, Zr,and Cecanbeassayeddependingonthelength
Radionuclides
of irradiation, purpose of the experiment, etc.
E261Practice for Determining Neutron Fluence, Fluence
4.3 The gamma rays emitted through radioactive decay are
Rate, and Spectra by Radioactivation Techniques
counted and the reaction rate, as defined in Practice E261,is
E262Test Method for Determining Thermal Neutron Reac-
calculated from the decay rate and the irradiation conditions.
tion Rates and Thermal Neutron Fluence Rates by Radio-
activation Techniques
4.4 Theneutronfluencerateforneutronswithenergiesfrom
approximately 0.7 to 6 MeV can then be calculated from the
spectral-weightedneutronactivationcrosssectionasdefinedin
1
ThistestmethodisunderthejurisdictionofASTMCommitteeE10onNuclear
Practice E261.
Technology and Applicationsand is the direct responsibility of Subcommittee
E10.05 on Nuclear Radiation Metrology. 238 237
4.5 Aparallelprocedurethatuses Uinsteadof Npis
Current edition approved July 1, 2008. Published October 2008. Originally
given in Test Method E704.
approved in 1979. Last previous edition approved 2002 as E705–96 (2002). DOI:
10.1520/E0705-08.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on The last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E705 − 08
TABLE 2 Recommended Fission Yields for Certain Fission
5. Significance and Use
A
Products
5.1 Refer to Practice E261 for a general discussion of the
B,A
Fissile Neutron Reaction Type ENDF/B-VII
determination of fast-neutron fluence rate with fission detec- Fission Yield (%)
Isotope Energy Product Yield
237 95
tors.
Np(n,f) 0.5 MeV Zr RC 5.66915 ± 2 %
99
Mo RC 6.11804 ± 4 %
237
5.2 Np is available as metal foil, wire, or oxide powder. 103
Ru RC 5.5583 ± 2.8 %
137
For further information, see Guide E844. It is usually encap- Cs RC 6.25127 ± 2 %
137m
Ba RI 1.141e-3 ± 64 %
sulated in a suitable container to prevent loss of, and contami-
140
Ba RC 5.488
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:E 705–96 Designation: E705 – 08
Standard Test Method for
Measuring Reaction Rates by Radioactivation of Neptunium-
1
237
This standard is issued under the fixed designation E705; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (ϵ) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 Thistestmethodcoversproceduresformeasuringreactionratesbyassayingafissionproduct(F.P.)fromthefissionreaction
237
Np(n,f)F.P.
1.2 The reaction is useful for measuring neutrons with energies from approximately 0.7 to 6 MeV and for irradiation times up
to 30 to 40 years.
1.3 Equivalent fission neutron fluence rates as defined in Practice E 261E261 can be determined.
1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E 261E261.
1.5
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.
2. Referenced Documents
2
2.1 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, Fluence, and Spectra by Radioactivation Techniques
E262 Test Method for Determining Thermal Neutron Reaction Rates and Thermal Neutron Fluence Rates by Radioactivation
Techniques
3
E320 Test MethodsMethod for Cesium-137 in Nuclear Fuel Solutions by Radiochemical Analysis
2
E393 Test Method for Measuring Reaction Rates by Analysis of Barium-140 from Fission Dosimeters
2
E482Guide for Application of Neutron Transport Methods for Reactor Vessel Surveillance, E706 (IID) Test Method for
Measuring Reaction Rates by Analysis of Barium-140 From Fission Dosimeters
E704 Test Method for Measuring Reaction Rates by Radioactivation of Uranium-238
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)
3. Terminology
3.1 Definitions:
3.1.1Refer to Terminology E 170E 170
3.1.1 Refer to Terminology E170.
1
ThistestmethodisunderthejurisdictionofASTMCommitteeE-10E10onNuclearTechnologyandApplicationsandisthedirectresponsibilityofSubcommitteeE10.05
on Nuclear Radiation Metrology.
Current edition approved Jan. 10, 1996. Published March 1996. Originally published as E 705–79. Last previous edition E 705–90.
Current edition approved July 1, 2008. Published October 2008. Originally approved in 1979. Last previous edition approved 2002 as E705–96 (2002). DOI:
10.1520/E0705-08.
2
ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,[e-mail] Annual Book of ASTM Standards
, Vol 12.02.volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Vanadium-encapsulated monitors of high purity are available from the Isotope Sales Div., Oak Ridge, TN 37830.
3
Withdrawn. The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
E705 – 08
4. Summary of Test Method
237
4.1 High-purity Np(<40ppmfissionableimpurity)isirradiatedinafast-neutronfield,therebyproducingradioactivefission
237
products from the reaction Np(n,f)F.P.
137 137m 1140 140 95 144
4.2 Various fission products such as Cs- Ba, Ba- La, Zr, and Ce can be assayed depending on the length of
irradiation, purpose of the experiment, etc.
4.3 The gamma rays emitted through radioactive decay are counted and the reaction rate, as defined in Practice E 261E261, is
calculated from the decay rate and the irradiation conditions.
4.4 The neutron fluence rate for neutrons with energies from approximately 0.7 to 6 MeV can then be calculated from the
spectral-weighted neutr
...