NUCLEAR REACTOR NEUTRON ENERGY SPECTRA by C Z Serpan, Jr and B H Menlce Naval Research Laboratory Washington, D C ASTM DATA SERIES PUBLICATION DS 52 List price $26.00 05-052000-35 AMERICAN SOCIETY FOR TESTING AND MATERIALS « 1916 Race Street, Philadelphia, Pa 19103 © by AMERICAN SOCIETY FOR TESTING AND MATERIALS 1974 Library of Congress Catalog Card Number: 74-75129 NOTE The Society is not responsible, as a body, for the statements and opinions advanced in this publication Printed in Baltimore, Md April 1974 Data Series DS 52 American Society for Testing and Materials Related ASTM Publications Analysis of Reactor Vessel Radiation Effects Surveillance Programs, ASTM STP 481 (1970), $26.00 (04-481000-35) Irradiation Effects on Structural Alloys for Nuclear Reactor Applications, ASTM STP 484 (1971), $49.25 (04-484000-35) Effects of Radiation on Substructure and Mechanical Properties of Metals and Alloys, ASTM STP 529 (1973), $49.50 (04-529000-35) TABLE OF CONTENTS Introduction Reactor Physics Spectrum Codes Description of Data in Main Compilation Reactor Description Spectrum Facility Description Spectrum Code Lower Energy Limit Neutron Flux Spectrum-Averaged Cross Sections Lethargy Lower Energy Limit (MeV) Flux Fraction Per Group Normalized Flux Per Lethargy Interval Use of Neutron Spectrum Data Normalized Flux Per Lethargy Interval Normalized Response Spectrum-Averaged Cross Sections Thermal Neutron Flux (at Maxwellian Temperature) Calculation of Fluxes from Cross Sections Flux Fraction Per Group References Main Compilation Light Water Moderated Reactors Research and Test Reactors SP LITR C-53 SP LITR C-49 SP LITR C-28 SP LITR C-18 SP LITR C-55 SP 21 LITR C-43 SP 82 UCRR T-C3 SP 83 UCRR T-D3 SP 84 UCRR T-B3 SP 85 UCRR T-A4 SP 86 UCRR T-F5 SP 60 ETR P-12 SP 61 ATR 1-D North Loop Power Reactors SP 23 Big Rock SP 24 Big Rock SP 25 Big Rock SP 26 Big Rock SP 27 Big Rock SP 28 Big Rock 4 4 5 6 6 7 9 10 11 12 13 17 17 17 45 Point Point Point Point Point Point -1 inch Accelerated +1 inch Vessel Wall Vessel Wall 1-inch into Surveillance Surveillance Cladding Interface vessel SP SP SP SP SP SP SP SP SP SP SP SP SP SP SP SP SP SP SP 29 30 31 32 14 15 33 45U 38 81 58 59 34 17U 16U 49 50 62 63 Big Rock Point 2-inch into vessel Big Rock Point 3-inch into vessel Big Rock Point 4-inch into vessel Big Rock Point 5-inch into vessel Yankee Inner Surveillance Monitor Yankee Outer Surveillance Monitor Yankee Vessel Wall Cladding Interface San Onofre Accelerated Surveillance SM-1A Vessel Wall Cladding Interface,Prog.S SM-1A Above Core Surveillance, Program S SM-1A Vessel Wall Cladding, PlMG SM-1A Above Core Surveillance, PlMG PM-2A Vessel Wall Cladding Interface,Prog.S PM-2A 1/4 t vessel thickness, Program S PM-2A 3/4 t vessel thickness, Program S PM-2A Vessel Wall Cladding Interface, PlMG PM-2A Vessel Wall Cladding Interface, P3MG SM-1 Dummy Fuel Element, Position 72 SM-1 Vessel Wall Cladding Interface Special Experimental Facilities IRL-4 4-5/8 inches SP IRL-4 5-5/8 inches SP 10 IRL-4 6-5/8 inches SP 11 IRL-4 7-5/8 inches SP 12 IRL-4 8-5/8 inches SP 13 IRL-5 Accelerated Surveillance DTF-IV SP 51D IRL-5 Vessel Wall Surveillance , DTF-IV SP 52D IRL-5 1-inch inside wall, DTF- IV SP 53D IRL-5 2-lnch inside wall, DTF- IV SP 54D SP 55D IRL-5 4-inch inside wall, DTF- IV IRL-5 6-inch inside wall, DTF- IV SP 56D IRL-5 7-inch inside*wall, DTF- IV SP 57D SP 51SA IRL-5 Accelerated Surveillance , SAND-II SP 52SA IRL-5 Vessel Wall Surveillance , SAND-II SP 53SA IRL-5 1-inch inside wall, SAND -II SP 55SA IRL-5 4-inch inside wall, SAND -II SP 57SA IRL-5 7-inch inside wall, SAND -II SP 51DB IRL-5 Accelerated Surveillance 2DB SP 52DB IRL-5 Vessel Wall Surveillance 2DB SP 53DB IRL-5 1-inch inside wall, 2DB SP 54DB IRL-5 2-inch inside wall, 2DB SP 55DB IRL-5 4-inch inside wall, 2DB SP 56DB IRL-5 6-inch inside wall, 2DB SP 57DB IRL-5 7-inch inside wall, 2DB SP 51PM IRL-5 Accelerated Surveillance , PlMG SP 52PM IRL-5 Vessel Wall Surveillance , PlMG SP 53PM IRL-5 1-inch inside wall, PlMG 97 SP 55PM SP 57PM IRL-5, 4-inch inside wall, P1MG IRL-5, 7-inch inside wall, P1MG 157 Heavy Water Moderated Reactors SP Carolinas-Virginia Tube Reactor, Pos 10-L Heavy Water Components Test Reactor, Gray Rod SP 22 Graphite Moderated Reactors SP Brookhaven Graphite Reactor, W-44 Position SP 39 GMWC, K-East Cold, No Shield SP 40 GMWC, K-East Cold, Intermediate Shield SP 41 GMWC, K-East Cold, Full Shield SP 42C K-East Cold, Cadmium SP 43CB K-East Cold, Cadmium plus Boron SP 39UH K-East 550°F, "O" Shield SP 42UH K-East 550°F, Cadmium Shield 163 Organic SP SP SP 181 Moderated Reactor 35 Organic Moderated Reactor Exp., Core Center 36 Organic Moderated Reactor Exp., Grid Plate 37 Organic Moderated Reactor Exp., Vessel Wall Fast Breeder Reactor 31F24 EBR II Control 31F25 EBR II Control 31F26 EBR II Control 31F27 EBR -II Control 31F28 EBR II Control 31F29 EBR II Control 31F30 EBR -II Control 31F31 EBR II Control 31F32 EBR II Control 31F33 EBR -II Control 31F34 EBR II Control 31F35 EBR II Control 189 Rod Rod Rod Rod Rod Rod Rod Rod Rod Rod Rod Rod Shroud Shroud Shroud Shroud Shroud Shroud Shroud Shroud Shroud Shroud Shroud Shroud 5D3 5D3 5D3 5D3 5D3 5D3 5A1 5A1 5A1 5A1 5A1 5A1 R R R R R R R R R R R R 18cm, Z +16.8cm 18cm, Z +31.7cm 18cm, Z +44.2cm 18cm, Z - 4.6cm 18cm, Z -18.3cm 18cm, Z -32.6cm 22.5cm,Z+16.8cm 22.5cm,Z+31.7cm 22.5cm,Z+44.2cm 22.5cm,Z- 4.6cm 22.5cm,Z-18.3cm 22.5cm,Z-32.6cm DS52-EB/Apr 1974 NUCLEAR REACTOR NEUTRON ENERGY SPECTRA C Z Serpan, Jr.* and B H Menke8 INTRODUCTION Studies of the effects resulting from exposure of materials to neutron bombardtaent in nuclear reactors can be made much more quantitative if the energy-level distribution of the neutrons is known Such a distribution is commonly called a neutron spectrum The neutron energies range from as low as x 10~10 MeV in the thermal-neutron region, to over 18 MeV in the fast region This extremely wide range can be conveniently handled, however, using a system of 25 or even fewer groups each defining a precise energy range, with the neutron population within those energy bounds being tabulated as the neutron spectrum A very common method in use for defining such a group structure is by quarter-lethargy units (0.25 u) where u is defined by (10 Mev\ x Mev) ' with 10 MeV typically taken as the highest energy boundary For example, using 10 MeV as the highest energy level boundary (and noting that all neutrons ^10 MeV are included in this group), the next lower energy level boundary would be -25ô-1ằ MVw) ã When all the neutrons in a spectrum having energies between any two such energy limits are summed and tabulated for that group, the neutrons are termed a group-integral flux and then the corresponding spectrum (all of the groups) is termed an integral spectrum The integral spectra presented in this compilation are listed in the column Flux Fraction Per Group a Reactor Materials Branch, Metallurgy Division, Naval Research Laboratory Copyright © 1974 by ASTM International www.astm.org Reactor Description Name: Experimental Breeder Reactor-II Power Level; Type: Fast, test Coolant :_Sfldlm_ Moderator: 62,5 MWt Location:National Rector Testing Station, Tdahn Falls, Triaho Spectrum Facility Description Control rod tnimble; R = IScm Z —32.6cm Spectrum Code Code: SAWP-H Lower Energy Limit >1 MeV ;>0.5 MeV >0.1 MeV Thermal, Calculation: WADCQ • Spectrum-Averaged Cross-Section J2x mb Neutron Flux* / -1 n/cm • sec 64.4 (1.08 x 10M+^ 22.7 -L2 -°C ~5i 54" Fast flux based on Fe(n,p) Mn reaction (8); Thermal flux 59 60 based on Co(n,y) Co reaction or Ag-Co technique (11) tin series of spectra 31F27 through 31F29 (below^5D3) S31F29 CRS 503 LETHARGY 0.25 0.50 0.75 1,00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00 3.25 3.50 3.75 4.00 5.00 6,75 a,oo 9,00 9,75 11,50 14.00 16,50 25,33 FILX FRACTI0N PER QR0UP 10HER ENERGY LIMIT JMEV) (U) , , , , , , ; , ; 7,79000*000 6,07000*000 4.72000*000 3,68000*000 2,87000*000 2,23000*000 1,74000*000 1,35000*000 1,05000*000 8,21000-001 6,39000-001 4,98000-001 3,08000-001 3,02000-001 2,35000-001 1,83000-001 6,74000-002 1,17000-002 3,36000-003 1,23000-003 5,83000-004 1,01000-004 8,32000-006 6,83000-007 1,00000-010 , 2,781-004 5.247-004 1,669-003 3.093-003 6,550-003 1.046-002 1,216-002 1.436-002 1.897-002 2.160-002 5,205-002 6.395-002 8.739-002 9.382-002 7.042-002 7.278-002 1.770-001 2.048-001 2,555-002 2.308-002 1.215-002 1.713-002 9.298-003 9.128-004 4,096-005 1.000*000 9N6 LETHARGY INTERVAL I 0.25U 201 NORMALIZED FLUX PER LETHARGY INTERVAL , , , , , , , , , 1796104*000 3770340*000 1716821*001 2718833*001 4763948*001 7729937*001 8762891*001 9796168*001 1732915*002 1754608*002 3765736*002 4751738*002 6716543*002 6759311*002 4794360*002 5712473*002 3712048*002 2705912*002 3760679*001 4704368*001 2786692*001 1772076*001 6755674*000 6742987-001 8716840-003 LETHARGY '(U) ior 10 1.23X10';"3 6.83X10" ENERGY 202 (MEV) 0,18 0.06 ID 0.*9 35 3.68 10 Reactor Description Name: Experimental Breeder Reactor-IT Power Level: Type: fast t9sX Moderator: Coolant: sndiun R2.S MWt Location: National Reactor Testing Station Idahn Falls, Trtahr Spectrum Facility Description Control rod tMmhle; R - 22 5om = -i-1 fi 8cm Spectrum Code Code: SAND-TT _Calculat ion: Lower Energy Limit Neutron Flux* -1 n/cm • sec >1 MeV >0.5 MeV (3.38 x IP14*) wAnrn 3E Spectrum-Averaged Cross-Section JU mb 780 40.3 >0.1 MeV 17.8 Thermal, - °C 53 53" Fe(n,p) Mn reaction (8); Thermal flux Fast flux,based on os t>u 60, based on 'Co(n,y) Co reaction or Ag-Co technique (11) tin series of spectra 31F30 through 31F32 (above05A1) S31F30 CRS 5A1 LETHARGY L8WER ENERGY LIMIT (MEV) (U) FLUX FRACTION PER GR8UP w 0.25 0.90 0,75 1,00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00 3.25 3.50 3.75 4.00 5.Q0 6.75 8.00 9.00 9.75 11.50 14,00 16,50 25.33 , ; 7,79000*000 6,07000*000 4,72000*000 3,68000*000 2,87000*000 2,23000*000 1,74000*000 1,35000*000 1,05000*000 8,21000.001 6,39000-001 4,98000-OQl 3,88000-001 3,02000-001 2,35000-001 1,83000-OQl 6,74000-002 1,17000-002 3.36000-003 1,23000-003 5,83000-004 1,01000-004 8,32000-OQ6 6,83000-007 1,00000-010 1.023-003 2.058-003 6.318-003 1.030-002 1.818-002 2,652-002 3.127-002 3,638-002 4.333-002 3.971-002 6.657-002 7.341-002 9,919-002 1.011-001 7.483-002 7,618-012 1.637-001 1.147-001 7.444-003 3.830-003 1.525-003 2.081-003 3.204-004 1.105-005 8.979-007 1.000*000 9NE LETHARGY INTERVAL I 0.25U 203 , N8RMALJZED FLUX PER LETHARGY INTERVAL 2735098*000 4773415*000 1744196*001 2737554*001 4719783*001 6:03155*001 7723221*001 8722768*001 9789480*001 9726382*001 1792451*002 1768997*002 2728080*002 2731595*002 1771217*002 1774810*002 9740649*001 3775891*001 3742437*000 2718745*000 1717223*000 6781340-001 7736678-002 2753716-003 5783652-005 25 IDT 10 LETHARGY 'oJ) 6- 83X10'-7 U23X10 -3 ENERGY 204 (MEV) O0I8 O0O6 1»35 0,t9 3c 68 10 Reactor Description Name: Experimental Breeder Reactor-II Power Level: Type: Fast, test Moderator: Coolant: Sodium 62.5 MWt Location: national Reactor Testing Station Idaho Falls Idaho Spectrum Facility Description Control rod thimble: R = 22.5cm Z = +31.7cm Spectrum Code Code: SAND-II Calculation: Lower Energy Limit WADCO 3B Spectrum-Averaged Cross-Section Neutron Flux* / • sec -1 n/cm _ >1 MeV 69.7 ^0.5 MeV 26.2 fl.22 x 10M +) _ >0.1 MeV 8.9 Thermal, _ °C "51 ST" Fast flux based on Fe(n,p) Mn reaction (8); Thermal flux based on 59Co(n,y)60Co reaction or Ag-Co technique (11) tin series of spectra 31F30 through 31F32 (aboveq_5Al) S31F31 CRS 9A1 LETHARGY , 1 MeV 81.4 >0.5 MeV 46.1 (5.59 x 10M +) _ >0.1 MeV 22.7 _ Thermal, -C "54" ST" Fast flux 59based on60 Fe(n,p) Mn reaction (8); Thermal flux based on Co(n,y) Co reaction or Ag-Co technique (11) tin series of spectra 31F33 through 31F35 (below(V5A1) S31F33 CRS SAX LETHARGY , (U) 18WER ENERGY LIMIT (MEV) ; 7,79000*000 6.07000*000 4,72000*000 3,68000*000 2,87000*000 2,23000*000 1,74000*000 1,39000*000 1,05000*000 8,21000-001 6,39000-001 4,98000-001 3,88000-001 3,02000-001 2,35000-001 1,83000-001 6,74000-002 1,17000-002 3,36000-003 1,23000-003 9,83000-004 1.01000-004 8,32000-006 6.83000-OQ7 1,00000-010 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00 3,25 3.50 3.75 4.00 5.Q0 6.75 8.00 9.00 9.75 11.90 14.00 16,50 25,33 , , ; , , , FLUX FRACTJBN PER GRSUP * 1,486-003 3.272-003 8,727-003 1.404-002 2.486-002 3.640-002 4.244-002 4.772-002 5.525-002 4.822-002 7.256-002 7.538-002 1.010-001 1.033-001 7.814-002 7.985-002 1.385-001 6.417-002 2.497-003 2.164-003 9,660-006 1.092-005 1.089-009 1,099-009 1,632-006 1,000*000 8NE LETHARGY INTERVAL I 0.25U 209 , N8RHALIZBD FLUX PER LETHARGY INTERVAL , , , , , 2749910*000 5742134*000 1743409*001 2733164*001 4713349*001 5796297*001 7707069*001 7777222*001 9-Q8695*001 8,10231*001 1719673*002 1724987*002 1767318*002 1770*91*002 1728797*002 1731979*002 9773048*001 1751470*001 8,14142-001 8790049-001 5734630-003 2797992-003 1779630-003 1781799-003 7,63990-009 25 ior 10 20 r LETHARGY Tu) r 6.83X10 -7 1.23X10 -3 ENERGY (MEV) 210 0.18 0.06 1.35 0.19 3.68 10 Reactor Description Name; Tr.xperHment.a1 Rrqeder Beafit.nr-TT Power Level: 62.5 MWt Type: Fast, test Moderator: Coolant: Sodium Location: National Reactor Testing Station Idaho Falls Idaho Spectrum Facility Description Control, rod thimble; R = 22.5cm Z 18.3cm Spectrum Code Code; SANTWT Lower Energy Limit Calculation; WADCO 3E Spectrum-Averaged Cross-Section JCU mb 77.5 39.4 17.2 Neutron Flux* / -1 n/cm • sec >1 MeV >0.5 MeV (3,15 x l(Mt) >0.1 MeV Thermal, -°C * '—53 53" Fast flux based on Fe(n,p) Mn reaction (8); Thermal flux 59 60 based on Co(n,y) Co reaction or Ag-Co technique (11) tin series of spectra 31F33 through 31F35 (below0.5 MeV (9.02 x 10* 36 Spectrum-Averaged Cross-Section q, mb 67.4 22.9 t) >0.1 MeV 7.0 Thermal, -°C * "53 53 Fast flux based on Fe(n,p) Mn reaction (8); Thermal flux 59 60 based on Co(n,y) Co reaction or Ag-Co technique (11) tin series of spectra 31F33 through 31F35 (below