ENTRY M0243 20130611 M067M024300000001 SUBENT M0243001 20130611 M067M024300100001 BIB 15 37 M024300100002 TITLE Photofission of Th-232 near threshold. M024300100003 AUTHOR (D.J.S.Findlay,N.P.Hawkes,M.R.Sene) M024300100004 INSTITUTE (2UK HAR) M024300100005 REFERENCE (J,NP/A,458,217,1986) M024300100006 FACILITY (LINAC,2UK HAR) M024300100007 INC-SOURCE (BRST) M024300100008 DETECTOR (BF3) M024300100009 METHOD (EXTB) M024300100010 ANALYSIS (PLA) The modification of the Penfold-Leiss unfolding M024300100011 method with specifically accomodates the detailed M024300100012 behaviour of the bremsstrahlung spectrum near the M024300100013 endpoint. M024300100014 SAMPLE The Th-232 target with thicknesses between 2 mg/cm**2 M024300100015 and 4 g/cm**2. M024300100016 CORRECTION All distributions were corrected for background, M024300100017 dead-time and overlap. M024300100018 REL-REF (N,,D.J.S.Findlay,J,NIM,206,507,1983) Bremsstrahlung M024300100019 spectra Calculations. M024300100020 (N,,D.J.S.FINDLAY,J,NIM,213,353,1983) Unfolding M024300100021 method. M024300100022 (N,,G.EDWARDS+,J,ANE,8,105,1981) TRDG neutron M024300100023 multiplicity distribution. M024300100024 STATUS (TABLE) The data have been digitized in USA LLNL and M024300100025 obtained by CDFE in the form of data tables. M024300100026 COMMENT Measurements are presented of the photofission cross M024300100027 section and mean number nu of neutrons per fission M024300100028 for Th-232 made using bremsstrahlung from the M024300100029 harwell electron linear accelerator helios and a M024300100030 high efficiency neutron detector to record neutron M024300100031 multiplicity distributions. The cross section is M024300100032 interpreted in terms of fission barrier with shallow M024300100033 wells in two separate outer barriers. Interesting M024300100034 structure is observed in nu as a function of photon M024300100035 energy. M024300100036 HISTORY (19920421C) M024300100037 (20130611A) Corrected by V.Varlamov: REACTION, dates, M024300100038 STATUS, lowercase. M024300100039 ENDBIB 37 0 M024300100040 COMMON 1 3 M024300100041 EN-RSL-FW M024300100042 KEV M024300100043 80. M024300100044 ENDCOMMON 3 0 M024300100045 ENDSUBENT 44 0 M024300199999 SUBENT M0243002 20130611 M067M024300200001 BIB 5 24 M024300200002 REACTION (90-TH-232(G,F),,SIG,,BRS) M024300200003 ERR-ANALYS (DATA-ERR) Mean root-square errors are given. M024300200004 COMMENT The effective photon energy spectrum was constructed M024300200005 from linear combination of bremsstrahlung spectra at M024300200006 different endpoint energies. The width of the M024300200007 resolution function (FWHM) was about 80 keV. The raw M024300200008 data comprise the set of pairs of photoneutron M024300200009 multiplicity nu distributions corresponding to M024300200010 neighboring bremsstrahlung endpoint energies. The M024300200011 set of difference distributions was then regarded as M024300200012 a set of yield difference curves, one for each M024300200013 multiplicity, and these curves were separately M024300200014 unfolded to give cross sections for each M024300200015 multiplicity as a function of photon energy. The M024300200016 final stage in the data analysis was to fit the M024300200017 cross sections for individual multiplicities at the M024300200018 same photon energies with the TRDG (an extension of M024300200019 the terelly neutron multiplicity distribution to M024300200020 accomodate separate consideration of two fission M024300200021 fragments) neutron multiplicity distribution to M024300200022 obtain the number of fissions and hence sig(g,f) and M024300200023 nu. M024300200024 STATUS Data from Fig. 3. M024300200025 HISTORY (20130611A) Corrected by V.Varlamov: BRA -> BRS, M024300200026 ENDBIB 24 0 M024300200027 NOCOMMON 0 0 M024300200028 DATA 3 30 M024300200029 EN DATA DATA-ERR M024300200030 MEV MB MB M024300200031 5.321E+00 1.862E-02 9.00E-03 M024300200032 5.370E+00 2.338E-02 8.30E-03 M024300200033 5.418E+00 1.823E-01 M024300200034 5.467E+00 2.939E-01 M024300200035 5.516E+00 1.861E-01 M024300200036 5.571E+00 2.489E-01 M024300200037 5.620E+00 3.126E-01 M024300200038 5.674E+00 2.340E-01 M024300200039 5.723E+00 1.750E-01 9.20E-02 M024300200040 5.772E+00 3.000E-01 M024300200041 5.826E+00 7.479E-01 M024300200042 5.870E+00 1.578E+00 M024300200043 5.918E+00 3.694E+00 M024300200044 5.967E+00 4.272E+00 M024300200045 6.022E+00 5.255E+00 M024300200046 6.071E+00 4.544E+00 M024300200047 6.120E+00 5.707E+00 M024300200048 6.174E+00 7.633E+00 M024300200049 6.223E+00 9.796E+00 M024300200050 6.277E+00 1.134E+01 M024300200051 6.326E+00 1.200E+01 M024300200052 6.375E+00 1.177E+01 M024300200053 6.424E+00 8.827E+00 2.80E+00 M024300200054 6.511E+00 1.021E+01 M024300200055 6.609E+00 9.199E+00 M024300200056 6.707E+00 7.633E+00 1.10E+00 M024300200057 6.810E+00 6.334E+00 2.50E+00 M024300200058 6.913E+00 5.953E+00 3.05E+00 M024300200059 7.011E+00 1.234E+01 7.50E+00 M024300200060 7.114E+00 7.477E+00 3.05E+00 M024300200061 ENDDATA 32 0 M024300200062 ENDSUBENT 61 0 M024300299999 SUBENT M0243003 20130611 M067M024300300001 BIB 4 6 M024300300002 REACTION (90-TH-232(G,F),PR,NU,,BRS) M024300300003 Mean number of neutrons per fission. M024300300004 ERR-ANALYS (ERR-S) Statistical errors. M024300300005 STATUS Data from Fig. 4. M024300300006 HISTORY (20130611A) Corrected by V.Varlamov: M024300300007 PRT/FIS, BRA -> BRS. M024300300008 ENDBIB 6 0 M024300300009 NOCOMMON 0 0 M024300300010 DATA 3 32 M024300300011 EN DATA ERR-S M024300300012 MEV PRT/FIS PRT/FIS M024300300013 5.340E+00 2.387E+00 4.87E-01 M024300300014 5.386E+00 2.185E+00 1.35E-01 M024300300015 5.440E+00 2.142E+00 5.80E-02 M024300300016 5.487E+00 2.122E+00 5.20E-02 M024300300017 5.541E+00 2.051E+00 8.90E-02 M024300300018 5.595E+00 2.063E+00 9.70E-02 M024300300019 5.645E+00 2.098E+00 1.02E-01 M024300300020 5.692E+00 2.280E+00 1.40E-01 M024300300021 5.749E+00 2.462E+00 1.90E-01 M024300300022 5.792E+00 2.268E+00 1.72E-01 M024300300023 5.846E+00 2.193E+00 6.70E-02 M024300300024 5.896E+00 2.169E+00 4.10E-02 M024300300025 5.950E+00 2.173E+00 4.70E-02 M024300300026 5.997E+00 2.217E+00 7.30E-02 M024300300027 6.043E+00 2.276E+00 7.45E-02 M024300300028 6.105E+00 2.296E+00 1.04E-01 M024300300029 6.151E+00 2.264E+00 9.60E-02 M024300300030 6.205E+00 2.225E+00 9.50E-02 M024300300031 6.252E+00 2.236E+00 1.15E-01 M024300300032 6.306E+00 2.193E+00 1.27E-01 M024300300033 6.352E+00 2.110E+00 9.00E-02 M024300300034 6.406E+00 2.205E+00 1.45E-01 M024300300035 6.518E+00 2.154E+00 1.26E-01 M024300300036 6.638E+00 2.126E+00 9.40E-02 M024300300037 6.738E+00 2.114E+00 1.36E-01 M024300300038 6.839E+00 2.075E+00 1.45E-01 M024300300039 6.935E+00 1.920E+00 1.90E-01 M024300300040 7.040E+00 2.011E+00 3.19E-01 M024300300041 7.144E+00 2.023E+00 3.17E-01 M024300300042 7.245E+00 2.122E+00 4.18E-01 M024300300043 7.345E+00 2.327E+00 4.80E-01 M024300300044 7.445E+00 1.340E+00 6.80E-01 M024300300045 ENDDATA 34 0 M024300300046 ENDSUBENT 45 0 M024300399999 ENDENTRY 3 0 M024399999999