ENTRY 23060 20090619 22142306000000001 SUBENT 23060001 20090619 22142306000100001 BIB 17 62 2306000100002 TITLE Neutron capture of Th-232 in the unresolved resonance 2306000100003 region. 2306000100004 AUTHOR (N.Janeva, N.Koyumdjieva, K.Volev, A.Lukyanov, 2306000100005 A.Borella,A.Brusegan, F.Corvi, G.Lobo, P.Schillebeeckx)2306000100006 INSTITUTE (2ZZZGEL) A.Borella,A.Brusegan, F.Corvi, G.Lobo, 2306000100007 P.Schillebeeckx 2306000100008 (3BULBLA) N.Janeva, N.Koyumdjieva, K.Volev, A.Lukyanov 2306000100009 REFERENCE ((S,ISINN-11,286,200405)=(S,JINR-E3-2004-9,286,2004)) 2306000100010 Tables of res. parameters. C-S on Figures. 2306000100011 REL-REF (I,,A.Bensussan+,J,NIM,155,11,1978) Detailed 2306000100012 description of GELINA.2306000100013 (M,,F.Corvi+,J,NIM/A,265,475,1988) 2306000100014 (M,,F.Corvi+,C,79KNOX,162,1979) 2306000100015 Pulse-height weighting technique description. 2306000100016 FACILITY (LINAC,2ZZZGEL) GELINA, electron burst width 1 nanosec,2306000100017 repetition rate 800 Hz, average electron current 2306000100018 70 micro-A, electron average energy 100 MeV . 2306000100019 INC-SOURCE (TAGD) 2306000100020 INC-SPECT Well-collimated neutron beam of 6.4 cm. 2306000100021 B-10 anti-overlapping filter . Pb-filter to reduce 2306000100022 gamma-flash. 2306000100023 9 mm Na filter to obtain background at 2.8 keV. 2306000100024 Black resonance filters ( Al, Co, W, Ag) to evaluate 2306000100025 background for neutron flux measurement. 2306000100026 SAMPLE Metallic natural Th disk of 8 cm diameter,0.5mm thick,2306000100027 corresponding to 1.588E-3 at/b . 2306000100028 METHOD (TOF) Flight Base is 14.37 m. 2306000100029 TOF-amplitude events were recorded in list-mode. 2306000100030 (PHD) Pulse-height weighting technique to obtain a 2306000100031 detection efficiency proportional to total excitation 2306000100032 energy. 2306000100033 Background : time-independent component produced by 2306000100034 radioactive decay of sample was deduced from 2306000100035 measurement with closed beam; time-dependent component2306000100036 was measured by replacing the thorium sample with 2306000100037 0.5 mm thick Pb-208 sample of the same size. 2306000100038 DETECTOR (STANK) Pair of C6-D6 liquid scintillators of 10 cm 2306000100039 diameter and 7.5 cm height, oriented perpendicularly 2306000100040 to neutron beam direction. 2306000100041 (BF3) For Neutron Intensity Monitoring 2306000100042 (IOCH) Ionization chamber placed at 80 cm before 2306000100043 thorium sample - for neutron flux measurement. 2306000100044 Has a cathode loaded with two back-to-back layers of 2306000100045 about 40 microg/cm**2 B-10. 2306000100046 Shielding around detectors. 2306000100047 MONITOR (5-B-10(N,A)3-LI-7,,SIG) To capture yield. 2306000100048 ASSUMED (ASSUM1,90-TH-232(N,0),,EN) 2306000100049 (ASSUM2,90-TH-232(N,0),,EN) 2306000100050 (ASSUM3,90-TH-232(N,TOT),,TRN) at 21.8 eV resonance. 2306000100051 (ASSUM4,90-TH-232(N,TOT),,TRN) at 23.5 eV resonance. 2306000100052 Normalization constant K was determined from resonance2306000100053 shape analysis of well-isolated and nearly saturated 2306000100054 resonances at 21.8 eV and 23.5 eV with peak 2306000100055 transmission of respectively 4.7% and 0.9%, using 2306000100056 REFIT IRMM code. 2306000100057 ANALYSIS (RFN) R-matrix theory used in code REFIT IRMM . 2306000100058 CORRECTION For multiple scattering and self-shielding effect 2306000100059 (using SESH CODE). 2306000100060 For resolution and Doppler broadening. 2306000100061 For background and dead time. 2306000100062 STATUS (PRELM) 2306000100063 HISTORY (20090619C) M.M. 2306000100064 ENDBIB 62 0 2306000100065 COMMON 4 3 2306000100066 ASSUM1 ASSUM2 ASSUM3 ASSUM4 2306000100067 EV EV NO-DIM NO-DIM 2306000100068 21.8 23.5 0.047 0.009 2306000100069 ENDCOMMON 3 0 2306000100070 ENDSUBENT 69 0 2306000199999 SUBENT 23060002 20090619 22142306000200001 BIB 6 17 2306000200002 REACTION 1(90-TH-232(N,EL),,STF,,AV) Neutron strength function . 2306000200003 2(90-TH-232(N,G),,WID,,AV) 2306000200004 Average radiation width. 2306000200005 3(90-TH-232(N,0),,D) 2306000200006 REL-REF (N,,F.H.Froehner,J,NSE,103,119,1989) Code FITACS. 2306000200007 ANALYSIS To fit capture c-s and evaluate resonance parameters 2306000200008 in URR the codes SAMMY and FITACS (based on Hauser- 2306000200009 Feshbach theory with width fluctuations) were used. 2306000200010 The adjustable parameters are strength function, 2306000200011 distant level parameters, average radiation widths 2306000200012 (at E=0), whose energy dependence is specified via 2306000200013 the giant dipole model. 2306000200014 MISC-COL (MISC) Level distant parameter. 2306000200015 STATUS (TABLE) Table 1 of S,ISINN-11,287,200405. 2306000200016 (DEP,22699002) Dependent from capture cross-section of2306000200017 Subent 22699002. 2306000200018 ERR-ANALYS (DATA-ERR) Not specified. 2306000200019 ENDBIB 17 0 2306000200020 COMMON 2 3 2306000200021 EN-MIN EN-MAX 2306000200022 KEV KEV 2306000200023 4. 40. 2306000200024 ENDCOMMON 3 0 2306000200025 DATA 6 3 2306000200026 MOMENTUM L DATA 1DATA-ERR 1DATA 2DATA 3MISC 2306000200027 NO-DIM NO-DIM NO-DIM EV EV NO-DIM 2306000200028 1. 1.1261E-04 0.5E-7 0.0212 18.64 -0.140 2306000200029 2. 2.3220E-04 0.6E-7 0.0212 -0.140 2306000200030 3. 3.3941E-04 0.27E-6 0.0212 -0.140 2306000200031 ENDDATA 5 0 2306000200032 ENDSUBENT 31 0 2306000299999 SUBENT 23060003 20090619 22142306000300001 BIB 4 16 2306000300002 REACTION 1(90-TH-232(N,EL),,WID,,AV) 2306000300003 2(90-TH-232(N,G),,WID,,AV) 2306000300004 3(90-TH-232(N,0),,D) 2306000300005 REL-REF (N,,N.Koyumdjieva+,J,ZP/A,353,31,1995) 2306000300006 (N,,N.Koyumdjieva+,J,NSE,137,(2),194,2001) 2306000300007 Statistical modeling of resonant cross section 2306000300008 structure in URR. 2306000300009 ANALYSIS Average resonance parameters are deduced by fitting 2306000300010 the average capture data using the MINUIT code for 2306000300011 fitting and uncertainty analysis. 2306000300012 Initial values of resonance parameters - based on 2306000300013 JENDL-3.3 . 2306000300014 STATUS (TABLE) Table 2 of S,ISINN-11,287,200405. 2306000300015 (DEP,22699002) Dependent from capture cross-section of2306000300016 Subent 22699002. 2306000300017 (DEP,23060004) 2306000300018 ENDBIB 16 0 2306000300019 COMMON 2 3 2306000300020 EN-MIN EN-MAX 2306000300021 KEV KEV 2306000300022 4. 40. 2306000300023 ENDCOMMON 3 0 2306000300024 DATA 5 5 2306000300025 MOMENTUM L SPIN J DATA 1DATA 2DATA 3 2306000300026 NO-DIM NO-DIM EV EV EV 2306000300027 0. 0.5 0.17509E-2 0.25601E-1 17.900 2306000300028 1. 0.5 0.35012E-2 0.26900E-1 17.900 2306000300029 1. 1.5 0.17060E-2 0.26900E-1 8.950 2306000300030 2. 2. 0.90173E-3 0.21200E-1 8.950 2306000300031 2. 2. 0.61585E-3 0.21200E-1 6.000 2306000300032 ENDDATA 7 0 2306000300033 ENDSUBENT 32 0 2306000399999 SUBENT 23060004 20090619 22142306000400001 BIB 4 14 2306000400002 REACTION (90-TH-232(N,EL)90-TH-232,,RAD) 2306000400003 ANALYSIS Average resonance parameters are deduced by fitting 2306000400004 the average capture data using the MINUIT code for 2306000400005 fitting and uncertainty analysis. 2306000400006 Initial values of resonance parameters - based on 2306000400007 JENDL-3.3 . 2306000400008 REL-REF (N,,N.Koyumdjieva+,J,ZP/A,353,31,1995) 2306000400009 (N,,N.Koyumdjieva+,J,NSE,137,(2),194,2001) 2306000400010 Statistical modeling of resonant cross section 2306000400011 structure in URR. 2306000400012 STATUS (TABLE) Table 2 of S,ISINN-11,287,200405 . 2306000400013 (DEP,22699002) Dependent from capture cross-section of2306000400014 Subent 22699002. 2306000400015 (DEP,23060003) 2306000400016 ENDBIB 14 0 2306000400017 COMMON 2 3 2306000400018 EN-MIN EN-MAX 2306000400019 KEV KEV 2306000400020 4. 40. 2306000400021 ENDCOMMON 3 0 2306000400022 DATA 1 1 2306000400023 DATA 2306000400024 FERMI 2306000400025 8.94 2306000400026 ENDDATA 3 0 2306000400027 ENDSUBENT 26 0 2306000499999 ENDENTRY 4 0 2306099999999