ENTRY M0450 20230614 M125M0450 0 1 SUBENT M0450001 20230614 M125M0450 1 1 BIB 13 71 M0450 1 2 TITLE Absolute cross section versus energy of the M0450 1 3 Cu-63(gamma,n) and Cu-63(gamma,2n) reactions. M0450 1 4 AUTHOR (A.I.Berman,K.L.Brown) M0450 1 5 REFERENCE (J,PR,96,83,1954) M0450 1 6 INSTITUTE (1USASTF) M0450 1 7 FACILITY (LINAC,1USASTF) M0450 1 8 INC-SOURCE (BRST) M0450 1 9 METHOD (STTA,ACTIV,BCINT) The stacked-foil method. The M0450 1 10 reaction yields were measured by determining the M0450 1 11 radioactivity of the ten-minute copper-62 and M0450 1 12 three-hour copper-61 nuclei which results from the M0450 1 13 (gamma,n) and (gamma,2n) processes, respectively, in M0450 1 14 copper-63. The number of photoneutrons ejected from M0450 1 15 the copper foil was determined by counting the M0450 1 16 residual radioactivity of the Cu-62 and Cu-61 M0450 1 17 isotopes with 4pi scintillation counter. M0450 1 18 SAMPLE The natural-copper foils used in the (gamma,n) runs M0450 1 19 were 1.25-inch diameter disks 40 mg/cm2 thick, while M0450 1 20 the enriched foils were 0.5 inch x 0.75-inch strips M0450 1 21 totaling 65 mg/cm2. Highly-enriched copper-63 foils: M0450 1 22 copper oxide containing 99.4% copper-63. Foils M0450 1 23 ranging in thickness from 3 to 16 mg/cm2 and M0450 1 24 totaling 130 mg/cm2 were made. M0450 1 25 DETECTOR (SCIN) 4Pi scintillation counter: the foil was M0450 1 26 sandwiched between two flat anthracene crystals, M0450 1 27 1.-inch square and 0.125-inch thick, backed by two M0450 1 28 DuMont 6292 photomultipliers. M0450 1 29 ANALYSIS (UNFLD,PHDIF) The number of photoneutrons ejected M0450 1 30 from the copper foil was determined by counting the M0450 1 31 residual radioactivity of the Cu-62 and Cu-61 M0450 1 32 isotopes with 4pi scintillation counter. Activation M0450 1 33 points were taken at 2 MeV intervals. The cross M0450 1 34 sections were computed from experimental yield M0450 1 35 curves by applying the photon-difference method M0450 1 36 using bremsstrahlung distributions calculated at 2 M0450 1 37 MeV intervals for a 0.025-radiation-length copper M0450 1 38 radiator. M0450 1 39 CORRECTION The cross sections given were corrected for M0450 1 40 contributions caused by the competing three-hour M0450 1 41 activity of Cu-61 (from Cu-63(g,2n) reaction) for M0450 1 42 twelve-hour Cu-64 activity (from Cu-65(g,n) M0450 1 43 reaction) which was evaluated by counting it after M0450 1 44 decay of the three-hour Cu-61 activity and then M0450 1 45 correcting by extrapolating back to the original M0450 1 46 Cu-64 activity and for multiple scattering of the M0450 1 47 primary electrons from Linac in the foils increases M0450 1 48 the effective path length of the bremsstrahlung M0450 1 49 quanta and electrons in the rear foil relative to M0450 1 50 the first (a correction for this was applied which M0450 1 51 varied from 4.0 to 0.4% from 12 to 36 MeV). M0450 1 52 COMMENT Experimental values were found for the absolute cross M0450 1 53 section of both Cu-63(gamma,n) and (gamma,2n) M0450 1 54 reactions versus gamma-quanta energy from threshold M0450 1 55 to 36 MeV. Statistical and systematic errors were M0450 1 56 limited by the use of: M0450 1 57 (a) the direct electron beam of the Stanford 36 MeV M0450 1 58 linear accelerator, which produced M0450 1 59 bremsstrahlung immediately before and within M0450 1 60 the copper foils under bombardment, M0450 1 61 (b) an electron-beam collector which recorded the M0450 1 62 total accumulated charge in the incident flux, M0450 1 63 (c) a 4pi scintillation counter which measured the M0450 1 64 activity of the resultant Cu-62 and Cu-61, M0450 1 65 (d) electroplated foils of separated Cu-63 M0450 1 66 isotopes. M0450 1 67 HISTORY (19910218C) M0450 1 68 (20180228A) Corrected by SD and VV: Updated to new M0450 1 69 date formats, lower case, STATUS, PART-DET deleted, M0450 1 70 REACTION, ERR-ANALYS moved to SUBENTs 002 - 006. M0450 1 71 (20230614A) Corrected by V.Varlamov: DATA in SUBENT M0450 1 72 005. M0450 1 73 ENDBIB 71 0 M0450 1 74 NOCOMMON 0 0 M0450 1 75 ENDSUBENT 74 0 M0450 199999 SUBENT M0450002 20180228 M095M0450 2 1 BIB 5 10 M0450 2 2 REACTION (29-CU-63(G,N)29-CU-62,,SIG,,BRS) M0450 2 3 DECAY-DATA (29-CU-62,9.73MIN,B+) M0450 2 4 ERR-ANALYS (DATA-ERR) The error in the values of the integrated M0450 2 5 cross section. M0450 2 6 (ERR-1,1.,2.) An error of 1 to 2% arises from the M0450 2 7 calculation of the thick-target bremsstrahlung M0450 2 8 distribution M0450 2 9 STATUS (CURVE) Data from Fig. 5 from PR,96,83,1954. M0450 2 10 HISTORY (20180228A) Corrected by SD and VV: REACTION (BRS), M0450 2 11 DECAY-DATA, STATUS. M0450 2 12 ENDBIB 10 0 M0450 2 13 COMMON 2 3 M0450 2 14 ANAL-STEP DATA-ERR M0450 2 15 MEV PER-CENT M0450 2 16 2. 5. M0450 2 17 ENDCOMMON 3 0 M0450 2 18 DATA 2 9 M0450 2 19 EN DATA M0450 2 20 MEV MB M0450 2 21 13. 20.5 M0450 2 22 15. 48. M0450 2 23 17. 96. M0450 2 24 19. 73. M0450 2 25 21. 14.5 M0450 2 26 23. 12. M0450 2 27 25. 5. M0450 2 28 27. 2.5 M0450 2 29 29. .5 M0450 2 30 ENDDATA 11 0 M0450 2 31 ENDSUBENT 30 0 M0450 299999 SUBENT M0450003 20180228 M095M0450 3 1 BIB 5 7 M0450 3 2 REACTION (29-CU-63(G,2N)29-CU-61,,SIG,,BRS) M0450 3 3 DECAY-DATA (29-CU-61,3.32HR,B+) M0450 3 4 ERR-ANALYS (DATA-ERR) The error in the values of the integrated M0450 3 5 cross section. M0450 3 6 STATUS (CURVE) Data from Fig. 6 from PR,96,83,1954. M0450 3 7 HISTORY (20180228A) Corrected by SD and VV: REACTION (BRS), M0450 3 8 DECAY-DATA, STATUS. M0450 3 9 ENDBIB 7 0 M0450 3 10 COMMON 1 3 M0450 3 11 DATA-ERR M0450 3 12 PER-CENT M0450 3 13 20. M0450 3 14 ENDCOMMON 3 0 M0450 3 15 DATA 2 8 M0450 3 16 EN DATA M0450 3 17 MEV MB M0450 3 18 21. 4.05 M0450 3 19 23. 6.55 M0450 3 20 25. 12.2 M0450 3 21 27. 10.05 M0450 3 22 29. 3.6 M0450 3 23 31. 3.2 M0450 3 24 33. 2.1 M0450 3 25 35. 1.05 M0450 3 26 ENDDATA 10 0 M0450 3 27 ENDSUBENT 26 0 M0450 399999 SUBENT M0450004 20180228 M095M0450 4 1 BIB 3 8 M0450 4 2 REACTION ((29-CU-63(G,2N)29-CU-61,,SIG,,BRS)/ M0450 4 3 ((29-CU-63(G,N)29-CU-62,,SIG,,BRS)+ M0450 4 4 (29-CU-63(G,2N)29-CU-61,,SIG,,BRS))) M0450 4 5 STATUS (DEP,M0450002) M0450 4 6 (DEP,M0450003) M0450 4 7 (TABLE) Data from Table II of PR,96,83,1954. M0450 4 8 HISTORY (20180228U) Corrected by SD and VV: REACTION (BRS), M0450 4 9 STATUS. M0450 4 10 ENDBIB 8 0 M0450 4 11 NOCOMMON 0 0 M0450 4 12 DATA 2 4 M0450 4 13 EN DATA M0450 4 14 MEV NO-DIM M0450 4 15 21. 0.13 M0450 4 16 23. 0.43 M0450 4 17 25. 0.71 M0450 4 18 27. 0.79 M0450 4 19 ENDDATA 6 0 M0450 4 20 ENDSUBENT 19 0 M0450 499999 SUBENT M0450005 20230614 M125M0450 5 1 BIB 4 14 M0450 5 2 REACTION (29-CU-63(G,N)29-CU-62,,INT,,BRS) M0450 5 3 ERR-ANALYS (DATA-ERR) The error in the values of the integrated M0450 5 4 cross section. M0450 5 5 No information on the source of the uncertainty. M0450 5 6 (ERR-1,1.,2.) An error of 1 to 2% arises from the M0450 5 7 calculation of the thick-target bremsstrahlung M0450 5 8 distribution. The limit of accuracy of the electron M0450 5 9 collector is 2%, and fluctuactions in foil mass per M0450 5 10 unit area constitute the remainder of the major M0450 5 11 errors. M0450 5 12 STATUS (TABLE) Data from Table III of PR,96,83,1954. M0450 5 13 HISTORY (20180228U) Corrected by SD and VV: STATUS. M0450 5 14 (20230614A) Corrected by V.Varlamov: ERR-ANALYS, M0450 5 15 REACTION, DATA, DATA-ERR deleted. M0450 5 16 ENDBIB 14 0 M0450 5 17 COMMON 1 3 M0450 5 18 DATA-ERR M0450 5 19 PER-CENT M0450 5 20 5. M0450 5 21 ENDCOMMON 3 0 M0450 5 22 DATA 3 1 M0450 5 23 EN-MIN EN-MAX DATA M0450 5 24 MEV MEV MB*MEV M0450 5 25 11. 35. .55 M0450 5 26 ENDDATA 3 0 M0450 5 27 ENDSUBENT 26 0 M0450 599999 SUBENT M0450006 20180228 M095M0450 6 1 BIB 4 5 M0450 6 2 REACTION (29-CU-63(G,2N)29-CU-61,,INT) M0450 6 3 ERR-ANALYS (DATA-ERR) The error in the values of the integrated M0450 6 4 cross section. M0450 6 5 STATUS (TABLE) Data from the text on p.89 of PR,96,83,1954. M0450 6 6 HISTORY (20180228U) SD+VV: STATUS added. M0450 6 7 ENDBIB 5 0 M0450 6 8 COMMON 1 3 M0450 6 9 DATA-ERR M0450 6 10 PER-CENT M0450 6 11 20. M0450 6 12 ENDCOMMON 3 0 M0450 6 13 DATA 3 1 M0450 6 14 EN-MIN EN-MAX DATA M0450 6 15 MEV MEV MB*MEV M0450 6 16 20. 36. .081 M0450 6 17 ENDDATA 3 0 M0450 6 18 ENDSUBENT 17 0 M0450 699999 ENDENTRY 6 0 M045099999999