ENTRY 30416 20090310 31353041600000001 SUBENT 30416001 20090310 31353041600100001 BIB 14 34 3041600100002 INSTITUTE (3BULBLA) 3041600100003 (2GERZFK) 1st author's address 3041600100004 REFERENCE (J,IP,12,(12),470,197612) in German. 3041600100005 (J,IP,13,(1),15,197701) Detail of method, in German. 3041600100006 AUTHOR (G.Pfrepper,C.Raitschev,D.Apostolov) 3041600100007 TITLE -Determination of the cross-section of Cl-37(n,p)S-37 3041600100008 reaction for fission neutrons.- 3041600100009 FACILITY (REAC,3BULBLA) Research reactor at Institut fuer 3041600100010 Kernforschung u. Kern Energetik, Sofia. 3041600100011 INC-SOURCE (REAC) N-flux = 4.x 10**12 n/sec/cm 3041600100012 INC-SPECT The flux ratio of thermal to fission neutrons,F(t)/F(s)3041600100013 was determined to be ' 5.7 ' using the reactions of 3041600100014 S-32(n,p)P-32 (=69 mb for fission neutrons) and 3041600100015 P-31(n,g)P-32 (=190mb for thermal neutrons),and their 3041600100016 cadmium ratios, 1 and 68, respectively. 3041600100017 SAMPLE 150-200 mg NH(4)-Cl, and 150-300 mg (NH(4))*2-SO(4) 3041600100018 as sulphur standard in polyethylen capsule. 3041600100019 METHOD (CHSEP,MOMIX) 3041600100020 NH(4)-Cl was irradiated 5 min with (NH(4))*2-SO(4). 3041600100021 After chemical separation, 3.13 MeV gamma peak from 3041600100022 S-37 was measured with Ge(Li) detector. 3041600100023 DETECTOR (GELI) 18 cm3 Ge(Li) detector with DIDAC 4000 multi- 3041600100024 channel analyzer. 3041600100025 .Bell-shape counter,VA-Z-310 and radiation detectors, 3041600100026 VA-V-100,VA-G-120 and VA-G-24A,( VEB Messelektronik, 3041600100027 Dresden), for beta counter. 3041600100028 PART-DET (DG,B-) 3041600100029 Decay gamma of 3.13 MeV from S-37 and B- of P-32. 3041600100030 STATUS (APRVD) Approved by Pfrepper(through Seeliger,78/04/25)3041600100031 HISTORY (19770713C) KO.- 3041600100032 (19790925U) KO.-'Aprvd' added. Minor correction in BIB.3041600100033 (20090310A) SD:Updated to new date formats,lower case. 3041600100034 ERR-ANALYS Standard deviation of the mean value of 12 different 3041600100035 experimental runs. 3041600100036 ENDBIB 34 0 3041600100037 NOCOMMON 0 0 3041600100038 ENDSUBENT 37 0 3041600199999 SUBENT 30416002 20090310 31353041600200001 BIB 5 24 3041600200002 REACTION (17-CL-37(N,P)16-S-37,,SIG,,FIS) 3041600200003 ANALYSIS The cross-section of Cl-37(n,p)S-37 for fission neutron3041600200004 sig(S) is deduced from the equation, 3041600200005 sig(S)=sig(t)*(F(t)/F(S))*(1/p)*(r/(r-1))*(1/r'), 3041600200006 where 3041600200007 sig(t)- (n,g) cross-section for 'thermal' neutrons, 3041600200008 F(t)/F(S)- flux ratio of thermal to fission neutron, 3041600200009 p - isotopic disturbing coef. of threshold reaction, 3041600200010 which is determined to measure the relative activity 3041600200011 of target and standard, 3041600200012 r - cadmium ratio of (n,g) reaction, 3041600200013 r'- cadmium ratio of threshold reaction.(now (n,p)) 3041600200014 Cadmium ratios for S-36(n,g)S-37 and Cl-37(n,p)S-37 3041600200015 were determined to be 87.5 and 1, respectively. 3041600200016 MONITOR ((MONIT1)16-S-36(N,G)16-S-37,,SIG,,MXW) = 150 mb, 3041600200017 ((MONIT2)16-S-32(N,P)15-P-32,,SIG,,FIS) = 69 mb, 3041600200018 ((MONIT3)15-P-31(N,G)15-P-32,,SIG,,MXW) = 190 mb. 3041600200019 .S-32(n,p)p-32 and P-31(n,g)P-32 reactions were used 3041600200020 to determine the flux ratio of thermal and fission 3041600200021 neutrons. 3041600200022 MONIT-REF ((MONIT1),R.SHER,R,IAEA-156,1,1974) 3041600200023 ((MONIT2),A.CALAMAND,R,IAEA-156,273,1974) 3041600200024 ((MONIT3),A.CALAMAND,R,IAEA-156,273,1974) 3041600200025 STATUS (TABLE) Data from Isotopenpraxis,12(1976)470. 3041600200026 ENDBIB 24 0 3041600200027 COMMON 3 3 3041600200028 MONIT1 MONIT2 MONIT3 3041600200029 MB MB MB 3041600200030 1.5000E+02 6.9000E+01 1.9000E+02 3041600200031 ENDCOMMON 3 0 3041600200032 DATA 3 1 3041600200033 EN-DUMMY DATA DATA-ERR 3041600200034 MEV MB MB 3041600200035 2.0000E+00 1.3500E-01 9.0000E-03 3041600200036 ENDDATA 3 0 3041600200037 ENDSUBENT 36 0 3041600299999 ENDENTRY 2 0 3041699999999