ENTRY            23159   20120731                             22332315900000001 
SUBENT        23159001   20120731                             22332315900100001 
BIB                 12         55                                 2315900100002 
AUTHOR     (S.Oberstedt, A.Oberstedt, E.Birgersson,I.Fabry,       2315900100003 
           F.-J.Hambsch, N.Kornilov, G.Loevestam,A.Tudora)        2315900100004 
TITLE      First results on the neutron-induced fission cross     2315900100005 
            section of 231-Pa for incident neutron energies       2315900100006 
           En > 17 MeV .                                          2315900100007 
INSTITUTE  (2ZZZGEL)  S.Oberstedt,I.Fabry,F.-J.Hambsch,           2315900100008 
                      G.Loevestam, N.Kornilov .                   2315900100009 
           (2SWDSWD)  A.Oberstedt, Dept.of Natural Sciences,      2315900100010 
                      Oerebro University, Sweden                  2315900100011 
           (3RUMBUU)  A.Tudora                                    2315900100012 
REFERENCE  (J,ANE,43,26,2012)  Data Table.                        2315900100013 
           #doi:10.1016/j.anucene.2011.12.023                     2315900100014 
FACILITY   (VDG,2ZZZGEL)                                          2315900100015 
MONITOR    (93-NP-237(N,F),,SIG)                                  2315900100016 
METHOD     (TOF)                                                  2315900100017 
DETECTOR   (FISCH)   Frisch-gridded fission chamber .             2315900100018 
           (SCIN) Three NE213 scintillation detectors employing   2315900100019 
           the pulse-shape discrimination technique for efficient 2315900100020 
           neutron/gamma-ray separation were placed at 0, 30, 60  2315900100021 
           degrees relative to the deuteron beam axis and 4.598 m 2315900100022 
           away from the neutron source and used to measure energy2315900100023 
           distributions from the neutron source at En = 16, 19,  2315900100024 
           20,21 MeV. Neutron spectra at 0degree, corrected for   2315900100025 
           pulse-height dependent efficiency, were used for the   2315900100026 
           neutron background correction and are shown in Fig.3   2315900100027 
           of J,ANE,43,26,2012.                                   2315900100028 
           The efficiency calibration of the neutron detectors was2315900100029 
           performed with a 252Cf spontaneous fission source (see 2315900100030 
           REL-REF of N.Kornilov+).                               2315900100031 
SAMPLE      Pa-231 sample was obtained by means of spray-painting.2315900100032 
            Original diameter 28 mm was reduced by collimator to  2315900100033 
            6 mm, effective mass determined by alpha-spectrometry 2315900100034 
            53.4+-1.3 microgram.                                  2315900100035 
            Np-237 sample of 28 mm diameter, mass 182.2 microgram 2315900100036 
           +- 1.7%, isotopic purity 99.9 %, with negligible       2315900100037 
           fractions of 238U and 238Pu of less than 2E-7 and 4E-8,2315900100038 
           respectively.                                          2315900100039 
           Protactinium sample was mounted on one side of the     2315900100040 
           chamber together with a well-characterized 237Np sample2315900100041 
           in back-to-back geometry.                              2315900100042 
           The distance between sample and neutron source - 60 mm.2315900100043 
REL-REF    (N,,C.Budtz-Joergensen+,J,NIM/A,258,209,1987)          2315900100044 
            Details of Frisch-grid fission chamber construction.  2315900100045 
           (M,,N.V.Kornilov+,J,NIM/A,599,226,2009)                2315900100046 
            Efficiency calibration details.                       2315900100047 
CORRECTION Fraction of fission fragments,which are absorbed in the2315900100048 
           sample due to neutron momentum transfer - estimated    2315900100049 
           particle leakage amounts to (2.4 +-0.6)% at En = 21MeV.2315900100050 
           Without any significant error (smaller than 1.5%)      2315900100051 
           authors assume that, due to considerable energy loss in2315900100052 
           the target at large emission angles, about half of the 2315900100053 
           events escape detection.                               2315900100054 
           For alpha-particles pile-up.                           2315900100055 
           For dead time - < 4.%.                                 2315900100056 
HISTORY    (20120731C)  M.M.                                      2315900100057 
ENDBIB              55          0                                 2315900100058 
NOCOMMON             0          0                                 2315900100059 
ENDSUBENT           58          0                                 2315900199999 
SUBENT        23159002   20120731                             22332315900200001 
BIB                  5         19                                 2315900200002 
REACTION   (91-PA-231(N,F),,SIG)                                  2315900200003 
INC-SOURCE (P-T) For reliability check of the experimental set-up,2315900200004 
           author switched from a deuteron beam to protons in     2315900200005 
           order to produce neutrons with energies En = 1.95 and  2315900200006 
           2.95 MeV. Practically the same fission cross-sections  2315900200007 
           were measured as published by S.Oberstedt+(2005),      2315900200008 
           which gives evidence for the reproducibility of present2315900200009 
           results.                                               2315900200010 
REL-REF    (A,22910002,S.Oberstedt+,J,ANE,32,1867,2005)           2315900200011 
ERR-ANALYS (ERR-T) Total uncertainty include                      2315900200012 
           - the uncertainties in the obtained number of fission  2315900200013 
           events for 231Pa and 237Np, which comprises both the   2315900200014 
           statistical as well as the systematic errors,          2315900200015 
           (MONIT-ERR) the uncertainty in fission cross-section of2315900200016 
            the reference isotope 237Np,                          2315900200017 
           - the ones of the effective sample masses,             2315900200018 
           - the uncertainty related to the low-energy neutron    2315900200019 
           background.                                            2315900200020 
STATUS     (TABLE) Table 1 of J,ANE,43,26,2012  .                 2315900200021 
ENDBIB              19          0                                 2315900200022 
COMMON               1          3                                 2315900200023 
MONIT-ERR                                                         2315900200024 
B                                                                 2315900200025 
0.03                                                              2315900200026 
ENDCOMMON            3          0                                 2315900200027 
DATA                 6          3                                 2315900200028 
EN         EN-RSL-HW  DATA       -ERR-T     +ERR-T     MONIT      2315900200029 
MEV        MEV        B          B          B          B          2315900200030 
1.95        0.08       1.15       0.08      0.08       1.67       2315900200031 
1.95        0.08       1.04       0.04      0.04       1.67       2315900200032 
2.95        0.06       1.00       0.04      0.04       1.63       2315900200033 
ENDDATA              5          0                                 2315900200034 
ENDSUBENT           33          0                                 2315900299999 
SUBENT        23159003   20120731                             22332315900300001 
BIB                  6         26                                 2315900300002 
REACTION  1(91-PA-231(N,F),,SIG)                                  2315900300003 
          2(91-PA-231(N,F),,SIG)                                  2315900300004 
INC-SOURCE (D-T) Quasi monoenergetic neutrons.                    2315900300005 
           Corresponding energy spread of the neutron beams,      2315900300006 
           calculated with the computer code EnergySet ( see      2315900300007 
           G.Loevestam, Program to calculate accelerator setting  2315900300008 
           and neutron yield data for the IRMM VdG laboratory,    2315900300009 
           IRMM internal report GE/NP/2/2002/06/20.2002), are     2315900300010 
           given as the difference between maximum and mean       2315900300011 
           neutron energy.                                        2315900300012 
CORRECTION Two different neutron-background evaluations :         2315900300013 
          1 -neutron background correction using the activation   2315900300014 
           data from A.Fessler et al. (2000),                     2315900300015 
          2 -using the neutron beam profiles measured in the frame2315900300016 
           of the cross-section measurements.                     2315900300017 
REL-REF   1(R,,A.Fessler+,J,NSE,134,171,2000)                     2315900300018 
ERR-ANALYS (ERR-T) Total uncertainty include                      2315900300019 
           - the uncertainties in the obtained number of fission  2315900300020 
           events for 231Pa and 237Np, which comprises both the   2315900300021 
           statistical as well as the systematic errors,          2315900300022 
           (MONIT-ERR) the uncertainty in fission cross-section of2315900300023 
            the reference isotope 237Np,                          2315900300024 
           - the ones of the effective sample masses,             2315900300025 
           - the uncertainty related to the low-energy neutron    2315900300026 
           background.                                            2315900300027 
STATUS     (TABLE) Table 1 of J,ANE,43,26,2012 .                  2315900300028 
ENDBIB              26          0                                 2315900300029 
NOCOMMON             0          0                                 2315900300030 
DATA                 9         12                                 2315900300031 
EN         EN-RSL-HW  DATA      1-ERR-T    1+ERR-T    1DATA      22315900300032 
ERR-T     2MONIT      MONIT-ERR                                   2315900300033 
MEV        MEV        B          B          B          B          2315900300034 
B          B          B                                           2315900300035 
 15.0        0.7       1.54       0.15       0.15       1.51      2315900300036 
 0.20       2.24       0.04                                       2315900300037 
 15.3        0.8       1.55       0.15       0.15       1.51      2315900300038 
 0.20       2.26       0.05                                       2315900300039 
 15.9        0.8       1.62       0.15       0.15       1.58      2315900300040 
 0.21       2.27       0.05                                       2315900300041 
 17.2        0.6       1.71       0.17       0.24       1.61      2315900300042 
 0.22       2.28       0.05                                       2315900300043 
 17.2        0.6       1.62       0.17       0.22       1.52      2315900300044 
 0.21       2.28       0.05                                       2315900300045 
 17.7        0.6       1.68       0.18       0.26       1.58      2315900300046 
 0.21       2.28       0.05                                       2315900300047 
 18.3        0.5       1.62       0.18       0.28       1.51      2315900300048 
 0.20       2.27       0.05                                       2315900300049 
 18.8        0.5       1.61       0.18       0.32       1.49      2315900300050 
 0.20       2.27       0.05                                       2315900300051 
 19.3        0.5       1.60       0.19       0.37       1.53      2315900300052 
 0.21       2.27       0.05                                       2315900300053 
 19.8        0.5       1.63       0.20       0.45       1.69      2315900300054 
 0.23       2.27       0.05                                       2315900300055 
 20.4        0.5       1.65       0.22       0.52       1.52      2315900300056 
 0.20       2.29       0.05                                       2315900300057 
 20.9        0.5       1.79       0.26       0.75       1.54      2315900300058 
 0.21       2.31       0.05                                       2315900300059 
ENDDATA             28          0                                 2315900300060 
ENDSUBENT           59          0                                 2315900399999 
SUBENT        23159004   20120731                             22332315900400001 
BIB                  5         19                                 2315900400002 
REACTION   (91-PA-231(N,F),,SIG)                                  2315900400003 
ANALYSIS   Fission cross-section and its total uncertainty are    2315900400004 
           calculated individually for both ways of data          2315900400005 
           treatment, and then averaged - weighted by their       2315900400006 
           individual uncertainties.                              2315900400007 
ERR-ANALYS (ERR-T) Total uncertainty include                      2315900400008 
           - the uncertainties in the obtained number of fission  2315900400009 
           events for 231Pa and 237Np, which comprises both the   2315900400010 
           statistical as well as the systematic errors,          2315900400011 
           (MONIT-ERR) the uncertainty in fission cross-section of2315900400012 
            the reference isotope 237Np,                          2315900400013 
           - the ones of the effective sample masses,             2315900400014 
           - the uncertainty related to the low-energy neutron    2315900400015 
           background.                                            2315900400016 
REL-REF    (A,21731003,O.Birgul+,J,RCA,11,108,1969)               2315900400017 
           (D,10929002,S.Plattard+,J,PRL,46,633,1981)             2315900400018 
STATUS     (TABLE) Table 1 of J,ANE,43,26,2012  .                 2315900400019 
           (DEP,23159003) Average of two treatments given in      2315900400020 
            Subent 003.                                           2315900400021 
ENDBIB              19          0                                 2315900400022 
NOCOMMON             0          0                                 2315900400023 
DATA                 7         12                                 2315900400024 
EN         EN-RSL-HW  DATA       -ERR-T     +ERR-T     MONIT      2315900400025 
MONIT-ERR                                                         2315900400026 
MEV        MEV        B          B          B          B          2315900400027 
B                                                                 2315900400028 
 15.0        0.7      1.52       0.18       0.18       2.24       2315900400029 
0.04                                                              2315900400030 
 15.3        0.8      1.54       0.18       0.18       2.26       2315900400031 
0.05                                                              2315900400032 
 15.9        0.8      1.61       0.18       0.19       2.27       2315900400033 
0.05                                                              2315900400034 
 17.2        0.6      1.66       0.20       0.23       2.28       2315900400035 
0.05                                                              2315900400036 
 17.2        0.6      1.57       0.19       0.21       2.28       2315900400037 
0.05                                                              2315900400038 
 17.7        0.6      1.63       0.20       0.24       2.28       2315900400039 
0.05                                                              2315900400040 
 18.3        0.5      1.56       0.19       0.25       2.27       2315900400041 
0.05                                                              2315900400042 
 18.8        0.5      1.54       0.19       0.27       2.27       2315900400043 
0.05                                                              2315900400044 
 19.3        0.5      1.56       0.20       0.30       2.27       2315900400045 
0.05                                                              2315900400046 
 19.8        0.5      1.67       0.22       0.35       2.27       2315900400047 
0.05                                                              2315900400048 
 20.4        0.5      1.56       0.21       0.40       2.29       2315900400049 
0.05                                                              2315900400050 
 20.9        0.5      1.61       0.23       0.55       2.31       2315900400051 
0.05                                                              2315900400052 
ENDDATA             28          0                                 2315900400053 
ENDSUBENT           52          0                                 2315900499999 
ENDENTRY             4          0                                 2315999999999