ENTRY L0049 19970129 0000L004900000001 SUBENT L0049001 19970129 0000L004900100001 BIB 14 69 L004900100002 INSTITUTE (1USALRL) L004900100003 REFERENCE (J,PR/C,21,503,8002) L004900100004 AUTHOR (J.W.JURY,B.L.BERMAN,D.D.FAUL,P.MEYER,J.G.WOODWORTH) L004900100005 TITLE Photoneutron cross sections for 17O. L004900100006 FACILITY (LINAC,1USALRL) L004900100007 INC-SOURCE (QMPH,ARAD) Positron annihilation in flight. L004900100008 The photon energy resolution (FWHM) ranged from L004900100009 approximately 220 keV at 8.5 MeV to 300 keV at 40 MeV L004900100010 SAMPLE 114-gram H2O sample, isotopic enriched to 54.8% 17O. L004900100011 16O (34.6%) and 180 (10.6%) contaminants. L004900100012 Sample was held in a thin-walled right-circular L004900100013 lucite cylinder of diameter 38 mm and length 100 mm. L004900100014 DETECTOR (BF3) 4pi neutron detector consisted of a 61-cm cube L004900100015 of paraffin containing 48 BF3 tubes arranged in four L004900100016 concentric rings around the beam line. L004900100017 METHOD (EXTB,RINGR) Direct photoneutron detection. L004900100018 Ring-ratio neutron multiplicity measurement. L004900100019 ANALYSIS After the recorded neutron events were corrected for L004900100020 pileup in the detector, the neutron backgrounds L004900100021 (annihilation target removed) were substracted for L004900100022 both the positron and electron measurements. L004900100023 Because the energy spectrum of the annihilation-plus- L004900100024 Bremsstrahlung radiation differs from that of purely L004900100025 Bremsstrahlung photons, a measured correction was L004900100026 applied to the ion-chamber (beam monitor) response to L004900100027 normalize the electron data to the positron data. L004900100028 The normalized electron data then were substracted fromL004900100029 the positron data, leaving the neutron counts which L004900100030 result only from the annihilation radiation. L004900100031 The measured sample-blank data, normalized to equal L004900100032 photon flux, were substracted from the target data to L004900100033 give the net target results. L004900100034 After a small correction for the neutron multiplicity L004900100035 in each ring, the data were corrected for the energy- L004900100036 dependent efficiency of the neutron detector using theL004900100037 ring-ratio result for each energy. L004900100038 The data were then converted to photoneutron cross L004900100039 sections by applying the measured ion-chamber responseL004900100040 per photon, the known number of target nuclei in the L004900100041 beam, and a small correction for the photon L004900100042 attenuation in the sample. L004900100043 CORRECTION Corrections were made for: L004900100044 - neutron multiplicity in each ring; L004900100045 - detector efficiency for each point; L004900100046 - atomic attenuation of photons in the sample; L004900100047 - ion-chamber response to electron and positron beams. L004900100048 ERR-ANALYS (DATA-ERR) Statistical errors only. L004900100049 Total systematic uncertainty arising from procedure L004900100050 of Bremsstrahlung-yield substraction, detector- L004900100051 efficiency correction, and ion-chamber calibration L004900100052 varies from about 7% below 20 mev to somewhat less L004900100053 than 20% at the highest energies measured. L004900100054 COMMENT The 6-MeV wide giant dipole resonance is observed to beL004900100055 centered at 23 MeV and a pygmy resonance is seen at L004900100056 about 13 MeV. Such structure as is apparent in the L004900100057 cross sections is not as pronounced as for the case L004900100058 of 16O and 18O. L004900100059 Comparison of the total photoneutron cross section withL004900100060 recent ground-state data indicates that much of the L004900100061 pygmy resonance decays to the ground or first excited L004900100062 state of 16O, but that the giant dipole resonance L004900100063 decays mainly to highly excited states in the daughterL004900100064 nucleus. L004900100065 Excellent agreement is observed between the present L004900100066 results and a recent two-particle, one-hole shell- L004900100067 model calculation of the isospin-split giant dipole L004900100068 resonance states for this nuclei. L004900100069 HISTORY (891207C) L004900100070 (950406A) BIB Updated L004900100071 ENDBIB 69 0 L004900100072 NOCOMMON 0 0 L004900100073 ENDSUBENT 72 0 L004900199999 SUBENT L0049002 19970129 0000L004900200001 BIB 2 3 L004900200002 REACTION (8-O-17(G,X)0-NN-1,UNW,SIG) L004900200003 The sum: (G,N)+(G,N+P)+(G,2N)+(G,2N+P). L004900200004 STATUS Converted from Berman compilation. L004900200005 ENDBIB 3 0 L004900200006 NOCOMMON 0 0 L004900200007 DATA 3 120 L004900200008 EN DATA DATA-ERR L004900200009 MEV MB MB L004900200010 8.507 0.51 0.13 L004900200011 8.754 0.25 0.20 L004900200012 8.877 1.08 0.18 L004900200013 9.001 0.57 0.16 L004900200014 9.124 0.66 0.14 L004900200015 9.371 0.38 0.12 L004900200016 9.618 0.66 0.13 L004900200017 9.988 0.95 0.14 L004900200018 10.358 0.78 0.16 L004900200019 10.728 0.77 0.15 L004900200020 10.852 0.99 0.19 L004900200021 10.975 1.21 0.17 L004900200022 11.099 1.30 0.14 L004900200023 11.222 1.34 0.15 L004900200024 11.345 1.39 0.19 L004900200025 11.469 1.27 0.14 L004900200026 11.592 1.31 0.14 L004900200027 11.716 1.24 0.14 L004900200028 11.839 1.27 0.14 L004900200029 11.962 1.32 0.15 L004900200030 12.086 1.37 0.12 L004900200031 12.209 1.63 0.15 L004900200032 12.333 2.00 0.16 L004900200033 12.456 1.95 0.16 L004900200034 12.579 1.70 0.17 L004900200035 12.703 1.76 0.18 L004900200036 12.826 1.95 0.19 L004900200037 12.950 2.25 0.20 L004900200038 13.073 1.97 0.23 L004900200039 13.196 1.70 0.20 L004900200040 13.320 1.85 0.22 L004900200041 13.443 2.40 0.30 L004900200042 13.567 2.06 0.32 L004900200043 13.690 2.21 0.31 L004900200044 13.813 1.82 0.30 L004900200045 13.937 1.55 0.27 L004900200046 14.060 1.63 0.26 L004900200047 14.184 1.58 0.23 L004900200048 14.307 1.71 0.24 L004900200049 14.430 1.49 0.23 L004900200050 14.554 1.48 0.24 L004900200051 14.677 1.15 0.24 L004900200052 14.801 0.96 0.25 L004900200053 14.924 0.87 0.24 L004900200054 15.171 1.27 0.23 L004900200055 15.418 1.32 0.21 L004900200056 15.664 0.91 0.21 L004900200057 15.911 1.08 0.19 L004900200058 16.158 1.42 0.22 L004900200059 16.405 1.26 0.23 L004900200060 16.652 1.27 0.27 L004900200061 16.898 1.14 0.25 L004900200062 17.145 1.49 0.25 L004900200063 17.392 1.47 0.16 L004900200064 17.639 1.43 0.21 L004900200065 17.886 1.38 0.21 L004900200066 18.132 1.81 0.24 L004900200067 18.379 2.23 0.25 L004900200068 18.626 2.18 0.26 L004900200069 18.873 2.64 0.27 L004900200070 19.120 3.20 0.29 L004900200071 19.366 3.63 0.28 L004900200072 19.613 3.75 0.27 L004900200073 19.860 4.07 0.29 L004900200074 20.107 4.93 0.32 L004900200075 20.354 5.50 0.31 L004900200076 20.600 5.38 0.31 L004900200077 20.847 5.09 0.33 L004900200078 21.094 5.66 0.34 L004900200079 21.341 7.03 0.40 L004900200080 21.588 8.08 0.39 L004900200081 21.834 9.25 0.42 L004900200082 22.081 11.17 0.47 L004900200083 22.328 11.61 0.51 L004900200084 22.575 11.45 0.49 L004900200085 22.822 12.90 0.52 L004900200086 23.068 13.27 0.55 L004900200087 23.192 13.28 0.55 L004900200088 23.315 12.97 0.56 L004900200089 23.439 12.53 0.55 L004900200090 23.562 12.12 0.58 L004900200091 23.685 11.31 0.59 L004900200092 23.809 10.64 0.60 L004900200093 23.932 10.78 0.60 L004900200094 24.056 11.48 0.60 L004900200095 24.179 10.86 0.58 L004900200096 24.302 10.39 0.58 L004900200097 24.426 10.55 0.58 L004900200098 24.549 11.01 0.58 L004900200099 24.673 10.16 0.58 L004900200100 24.796 9.85 0.63 L004900200101 25.043 9.34 0.66 L004900200102 25.290 8.78 0.66 L004900200103 25.536 9.11 0.73 L004900200104 25.783 7.95 0.70 L004900200105 26.030 7.19 0.76 L004900200106 26.277 7.75 0.71 L004900200107 26.524 7.38 0.73 L004900200108 26.770 6.70 0.72 L004900200109 27.017 6.34 0.73 L004900200110 27.264 6.41 0.77 L004900200111 27.511 6.30 0.79 L004900200112 27.758 6.88 0.85 L004900200113 28.251 5.98 0.93 L004900200114 28.745 5.23 1.09 L004900200115 29.238 5.09 1.31 L004900200116 29.732 3.68 0.74 L004900200117 30.226 4.72 1.31 L004900200118 30.472 2.89 1.27 L004900200119 31.213 4.64 1.26 L004900200120 31.953 3.39 1.35 L004900200121 32.694 3.47 1.35 L004900200122 33.434 2.84 1.44 L004900200123 34.174 2.37 1.41 L004900200124 34.915 2.91 1.43 L004900200125 35.655 3.72 1.35 L004900200126 36.396 2.57 1.29 L004900200127 37.136 3.30 1.30 L004900200128 37.876 2.33 1.24 L004900200129 39.728 2.63 1.05 L004900200130 ENDDATA 122 0 L004900200131 ENDSUBENT 130 0 L004900299999 SUBENT L0049003 19970129 0000L004900300001 BIB 2 3 L004900300002 REACTION ((8-O-17(G,N)8-O-16,,SIG)+(8-O-17(G,N+P)7-N-15,,SIG)) L004900300003 Threshold of the reaction (gamma,n+p) is 16.3 MeV. L004900300004 STATUS Converted from Berman compilation. L004900300005 ENDBIB 3 0 L004900300006 NOCOMMON 0 0 L004900300007 DATA 3 120 L004900300008 EN DATA DATA-ERR L004900300009 MEV MB MB L004900300010 8.507 0.51 0.13 L004900300011 8.754 0.25 0.20 L004900300012 8.877 1.08 0.18 L004900300013 9.001 0.57 0.16 L004900300014 9.124 0.66 0.14 L004900300015 9.371 0.38 0.12 L004900300016 9.618 0.66 0.13 L004900300017 9.988 0.95 0.14 L004900300018 10.358 0.78 0.16 L004900300019 10.728 0.77 0.15 L004900300020 10.852 0.99 0.19 L004900300021 10.975 1.21 0.17 L004900300022 11.099 1.30 0.14 L004900300023 11.222 1.34 0.15 L004900300024 11.345 1.39 0.19 L004900300025 11.469 1.27 0.14 L004900300026 11.592 1.31 0.14 L004900300027 11.716 1.24 0.14 L004900300028 11.839 1.27 0.14 L004900300029 11.962 1.32 0.15 L004900300030 12.086 1.37 0.12 L004900300031 12.209 1.63 0.15 L004900300032 12.333 2.00 0.16 L004900300033 12.456 1.95 0.16 L004900300034 12.579 1.70 0.17 L004900300035 12.703 1.76 0.18 L004900300036 12.826 1.95 0.19 L004900300037 12.950 2.25 0.20 L004900300038 13.073 1.97 0.23 L004900300039 13.196 1.70 0.20 L004900300040 13.320 1.85 0.22 L004900300041 13.443 2.40 0.30 L004900300042 13.567 2.06 0.32 L004900300043 13.690 2.21 0.31 L004900300044 13.813 1.82 0.30 L004900300045 13.937 1.55 0.27 L004900300046 14.060 1.63 0.26 L004900300047 14.184 1.58 0.23 L004900300048 14.307 1.71 0.24 L004900300049 14.430 1.49 0.23 L004900300050 14.554 1.48 0.24 L004900300051 14.677 1.15 0.24 L004900300052 14.801 0.96 0.25 L004900300053 14.924 0.87 0.24 L004900300054 15.171 1.27 0.23 L004900300055 15.418 1.32 0.21 L004900300056 15.664 0.91 0.21 L004900300057 15.911 1.08 0.19 L004900300058 16.158 1.42 0.22 L004900300059 16.405 1.26 0.23 L004900300060 16.652 1.27 0.27 L004900300061 16.898 1.14 0.25 L004900300062 17.145 1.49 0.25 L004900300063 17.392 1.47 0.16 L004900300064 17.639 1.43 0.21 L004900300065 17.886 1.38 0.21 L004900300066 18.132 1.81 0.24 L004900300067 18.379 2.23 0.25 L004900300068 18.626 2.18 0.26 L004900300069 18.873 2.64 0.27 L004900300070 19.120 3.20 0.29 L004900300071 19.366 3.56 0.26 L004900300072 19.613 3.89 0.26 L004900300073 19.860 3.99 0.27 L004900300074 20.107 4.84 0.30 L004900300075 20.354 5.72 0.29 L004900300076 20.600 5.42 0.29 L004900300077 20.847 5.01 0.31 L004900300078 21.094 5.73 0.32 L004900300079 21.341 6.98 0.38 L004900300080 21.588 8.08 0.37 L004900300081 21.834 9.17 0.39 L004900300082 22.081 10.47 0.43 L004900300083 22.328 10.91 0.47 L004900300084 22.575 10.77 0.45 L004900300085 22.822 12.46 0.48 L004900300086 23.068 12.25 0.50 L004900300087 23.192 12.00 0.49 L004900300088 23.315 11.71 0.51 L004900300089 23.439 11.86 0.49 L004900300090 23.562 11.20 0.52 L004900300091 23.685 10.39 0.53 L004900300092 23.809 10.06 0.54 L004900300093 23.932 9.80 0.54 L004900300094 24.056 10.69 0.54 L004900300095 24.179 10.33 0.52 L004900300096 24.302 9.93 0.53 L004900300097 24.426 9.79 0.53 L004900300098 24.549 9.54 0.52 L004900300099 24.673 9.56 0.52 L004900300100 24.796 9.05 0.57 L004900300101 25.043 8.18 0.60 L004900300102 25.290 7.48 0.60 L004900300103 25.536 7.98 0.67 L004900300104 25.783 7.09 0.66 L004900300105 26.030 6.10 0.72 L004900300106 26.277 6.73 0.65 L004900300107 26.524 6.61 0.67 L004900300108 26.770 5.80 0.66 L004900300109 27.017 4.63 0.67 L004900300110 27.264 5.72 0.71 L004900300111 27.511 5.90 0.73 L004900300112 27.758 5.32 0.77 L004900300113 28.251 4.50 0.86 L004900300114 28.745 4.43 1.01 L004900300115 29.238 3.98 1.23 L004900300116 29.732 2.88 0.69 L004900300117 30.226 3.70 1.23 L004900300118 30.472 1.70 1.21 L004900300119 31.213 3.01 1.18 L004900300120 31.953 1.84 1.28 L004900300121 32.694 2.31 1.26 L004900300122 33.434 1.90 1.34 L004900300123 34.174 1.12 1.30 L004900300124 34.915 0.85 1.29 L004900300125 35.655 2.18 1.23 L004900300126 36.396 1.49 1.17 L004900300127 37.136 2.68 1.15 L004900300128 37.876 1.76 1.08 L004900300129 39.728 2.43 0.92 L004900300130 ENDDATA 122 0 L004900300131 ENDSUBENT 130 0 L004900399999 SUBENT L0049004 19970129 0000L004900400001 BIB 3 5 L004900400002 REACTION ((8-O-17(G,2N)8-O-15,,SIG)+ L004900400003 (8-O-17(G,2N+P)7-N-14,,SIG)) L004900400004 Threshold of (gamma,2n+p) reaction is 27.1 MeV. L004900400005 STATUS Converted from Berman compilation. L004900400006 HISTORY (950406A) REACTION corrected. L004900400007 ENDBIB 5 0 L004900400008 NOCOMMON 0 0 L004900400009 DATA 3 59 L004900400010 EN DATA DATA-ERR L004900400011 MEV MB MB L004900400012 19.366 0.04 0.06 L004900400013 19.613 -0.07 0.06 L004900400014 19.860 0.04 0.06 L004900400015 20.107 0.04 0.07 L004900400016 20.354 -0.11 0.07 L004900400017 20.600 -0.02 0.07 L004900400018 20.847 0.04 0.08 L004900400019 21.094 -0.03 0.08 L004900400020 21.341 0.02 0.09 L004900400021 21.588 0.00 0.10 L004900400022 21.834 0.04 0.11 L004900400023 22.081 0.35 0.13 L004900400024 22.328 0.35 0.14 L004900400025 22.575 0.34 0.15 L004900400026 22.822 0.22 0.15 L004900400027 23.068 0.51 0.16 L004900400028 23.192 0.64 0.17 L004900400029 23.315 0.63 0.17 L004900400030 23.439 0.34 0.17 L004900400031 23.562 0.46 0.18 L004900400032 23.685 0.46 0.18 L004900400033 23.809 0.29 0.18 L004900400034 23.932 0.49 0.18 L004900400035 24.056 0.39 0.18 L004900400036 24.179 0.27 0.17 L004900400037 24.302 0.23 0.17 L004900400038 24.426 0.38 0.18 L004900400039 24.549 0.74 0.18 L004900400040 24.673 0.30 0.18 L004900400041 24.796 0.40 0.18 L004900400042 25.043 0.58 0.19 L004900400043 25.290 0.65 0.19 L004900400044 25.536 0.57 0.20 L004900400045 25.783 0.43 0.17 L004900400046 26.030 0.55 0.19 L004900400047 26.277 0.51 0.21 L004900400048 26.524 0.39 0.21 L004900400049 26.770 0.45 0.19 L004900400050 27.017 0.86 0.21 L004900400051 27.264 0.34 0.21 L004900400052 27.511 0.20 0.21 L004900400053 27.758 0.78 0.24 L004900400054 28.251 0.74 0.26 L004900400055 28.745 0.40 0.30 L004900400056 29.238 0.55 0.32 L004900400057 29.732 0.40 0.20 L004900400058 30.226 0.51 0.33 L004900400059 30.472 0.60 0.28 L004900400060 31.213 0.82 0.30 L004900400061 31.953 0.77 0.31 L004900400062 32.694 0.58 0.34 L004900400063 33.434 0.47 0.36 L004900400064 34.174 0.63 0.39 L004900400065 34.915 1.03 0.43 L004900400066 35.655 0.77 0.40 L004900400067 36.396 0.54 0.40 L004900400068 37.136 0.31 0.42 L004900400069 37.876 0.29 0.43 L004900400070 39.728 0.10 0.35 L004900400071 ENDDATA 61 0 L004900400072 ENDSUBENT 71 0 L004900499999 SUBENT L0049005 19970129 0000L004900500001 BIB 2 2 L004900500002 REACTION (8-O-17(G,2N)8-O-15,,INT) L004900500003 STATUS (DEP,L0049004) Data taken from TABLE 1 in article. L004900500004 ENDBIB 2 0 L004900500005 NOCOMMON 0 0 L004900500006 DATA 3 1 L004900500007 EN-MIN EN-MAX DATA L004900500008 MEV MEV MB*MEV L004900500009 19.81 39.7 9. L004900500010 ENDDATA 3 0 L004900500011 ENDSUBENT 10 0 L004900599999 SUBENT L0049006 19970129 0000L004900600001 BIB 2 2 L004900600002 REACTION ((8-O-17(G,N)8-O-16,,INT)+(8-O-17(G,N+P)7-N-15,,INT)) L004900600003 STATUS (DEP,L0049003) Data taken from TABLE 1 in article. L004900600004 ENDBIB 2 0 L004900600005 NOCOMMON 0 0 L004900600006 DATA 3 1 L004900600007 EN-MIN EN-MAX DATA L004900600008 MEV MEV MB*MEV L004900600009 4.14 39.7 111. L004900600010 ENDDATA 3 0 L004900600011 ENDSUBENT 10 0 L004900699999 SUBENT L0049007 19970129 0000L004900700001 BIB 2 2 L004900700002 REACTION ((8-O-16(G,N)8-O-15,,INT)+(8-O-16(G,N+P)7-N-14,,INT)) L004900700003 STATUS Data Taken from table 1 in article L004900700004 ENDBIB 2 0 L004900700005 NOCOMMON 0 0 L004900700006 DATA 3 1 L004900700007 EN-MIN EN-MAX DATA L004900700008 MEV MEV MB*MEV L004900700009 15.66 39.7 63. L004900700010 ENDDATA 3 0 L004900700011 ENDSUBENT 10 0 L004900799999 SUBENT L0049008 19970129 0000L004900800001 BIB 2 4 L004900800002 REACTION ((8-O-17(G,N)8-O-16,,INT)+ L004900800003 (8-O-17(G,N+P)7-N-15,,INT)+ L004900800004 (8-O-17(G,2N)8-O-15,,INT)) L004900800005 STATUS (DEP,L0049009) Data taken from TABLE 1 in article. L004900800006 ENDBIB 4 0 L004900800007 NOCOMMON 0 0 L004900800008 DATA 4 1 L004900800009 EN-MIN EN-MAX DATA DATA-ERR L004900800010 MEV MEV MB*MEV MB*MEV L004900800011 4.14 40. 120. 12. L004900800012 ENDDATA 3 0 L004900800013 ENDSUBENT 12 0 L004900899999 SUBENT L0049009 19970129 0000L004900900001 BIB 2 4 L004900900002 REACTION ((8-O-16(G,N)8-O-15,,SIG)+ L004900900003 (8-O-16(G,N+P)7-N-14,,SIG)+ L004900900004 (8-O-16(G,2N)8-O-14,,SIG)) L004900900005 STATUS (CURVE) Read from FIGURE 1 in article L004900900006 ENDBIB 4 0 L004900900007 NOCOMMON 0 0 L004900900008 DATA 3 55 L004900900009 EN DATA DATA-ERR L004900900010 MEV MB MB L004900900011 17.2 1.6 L004900900012 17.6 .5 L004900900013 18. .05 L004900900014 18.8 1.3 L004900900015 19.3 1.8 L004900900016 19.9 .3 L004900900017 20.1 .7 L004900900018 20.6 2. L004900900019 20.7 2.8 L004900900020 21. 2.6 L004900900021 21.2 2.8 .1 L004900900022 21.6 4.1 .1 L004900900023 22. 6. .1 L004900900024 22.1 8.4 .1 L004900900025 22.2 8. .1 L004900900026 22.5 5.3 .1 L004900900027 22.6 4.9 L004900900028 22.7 5.2 L004900900029 22.9 5.9 .1 L004900900030 23.2 5.8 .1 L004900900031 23.3 6. L004900900032 23.5 6.1 L004900900033 23.6 6.5 .1 L004900900034 23.7 6.7 .1 L004900900035 23.8 6.8 .1 L004900900036 24. 7. .1 L004900900037 24.3 7. .1 L004900900038 24.5 6.1 .1 L004900900039 24.7 5.4 .2 L004900900040 24.9 5.8 .2 L004900900041 25.1 5.7 .3 L004900900042 25.5 5.3 .2 L004900900043 25.7 4.6 .2 L004900900044 26. 4.5 .2 L004900900045 26.5 4.4 .2 L004900900046 26.7 4. .2 L004900900047 27. 3.5 .3 L004900900048 27.5 3.1 .3 L004900900049 28. 2.9 .3 L004900900050 28.5 2.7 .3 L004900900051 29. 3. .5 L004900900052 29.5 2.4 .2 L004900900053 30. 3. .3 L004900900054 30.3 2.4 .4 L004900900055 31.2 2.5 .4 L004900900056 32. 2.2 .3 L004900900057 32.6 2. .3 L004900900058 33.4 1.5 .4 L004900900059 34. 1.6 .4 L004900900060 34.9 1.6 .4 L004900900061 35.6 1.7 .5 L004900900062 36.3 1.6 .5 L004900900063 37. 1.8 .5 L004900900064 37.9 1.4 .5 L004900900065 38.8 1.9 .3 L004900900066 ENDDATA 57 0 L004900900067 ENDSUBENT 66 0 L004900999999 ENDENTRY 9 0 L004999999999