ENTRY 20672 19840127 00002067200000001 SUBENT 20672001 19840127 00002067200100001 BIB 14 54 2067200100002 INSTITUTE (2GERMUN) INSTITUT FUER RADIOCHEMIE DER TECHNISCHEN 2067200100003 UNIVERSITAET MUENCHEN. 2067200100004 REFERENCE (J,PR/C,12,(5),1507,7511) 2067200100005 AUTHOR (K.LINDEKE,S.SPECHT,H.J.BORN) 2067200100006 TITLE -DETERMINATION OF THE 237NP(N,2N)236NP CROSS SECTION 2067200100007 AT 15 MEV NEUTRON ENERGY- 2067200100008 FACILITY (VDG ) TYPE K 3000 VAN DE GRAAFF GENERATOR OF THE 2067200100009 GESELLSCHAFT FUER STRAHLEN-UND UMWELTFORSCHUNG, 2067200100010 NEUHERBERG. 2067200100011 INC-SOURCE (D-T ) THE ACCELERATED DEUTERON BEAM OF THE VAN DE 2067200100012 GRAAFF BOMBARDED A TRITIUM TARGET TO PRODUCE 15 MEV 2067200100013 NEUTRONS. 2067200100014 SAMPLE .THE 237-NP CONTAINED 236-PU,THE ACTIVITY OF WHICH 2067200100015 WAS LESS THEN 1PC OF THE RESULTANT ACTIVITY OF THE 2067200100016 PU-236, PRODUCED AFTER IRRADIATION. 2067200100017 .THE SAMPLE WAS IRRADIATED AS NPO2 IN A POLYETHYLENE 2067200100018 CAPSULE SURROUNDED BY CD. 2067200100019 METHOD (ACTIV,CHSEP) TWO INDEPENDENT METHODS WERE EMPLOYED. 2067200100020 .THE DIRECT MEASUREMENT OF GAMMA RAYS FOLLOWING 2067200100021 ELECTRON CAPTURE OF 236-NP TO 236-U. 2067200100022 .THE MEASUREMENT OF ALPHA PARTICLES OF THE 236-PU 2067200100023 (FROM BETA-DECAY OF 236-NP) AFTER CHEMICAL 2067200100024 SEPARATION. 2067200100025 DETECTOR (GELI ) THE GE(LI) WAS USED IN THE GAMMA MEASUREMENT. 2067200100026 (SOLST) A SI SURFACE BARRIER DETECTOR WAS USED FOR 2067200100027 ALPHA COUNTING. 2067200100028 MONITOR .THE REACTION 27AL(N,ALPHA)24NA WAS USED 2067200100029 AS A NORMALIZING STANDARD FOR THE INCIDENT FLUX. 2067200100030 SEE H.VONACH ET AL.,Z.PHYS.,237,155(1970),THE DECAY 2067200100031 -GAMMAS OF THE 24-NA WERE MEASURED BY A GE(LI) 2067200100032 DETECTOR (FLUX-6.77+-0.24X10E+13 NEUTRONS PER CM2). 2067200100033 .A SECOND STANDARD WAS PROVIDED BY THE DETERMINATION 2067200100034 OF THE ACTIVITY OF THE FISSION PRODUCT 97-ZR. 2067200100035 FLUX-6.40+-0.73X10E+13 NEUTRONS PER CM2. 2067200100036 STATUS .DATA FOR THE CROSS SECTION OF THE REACTION 2067200100037 237NP(N,2N)236NP TAKEN FROM REFERENCE. 2067200100038 HISTORY (761027C) 2067200100039 (770504E) 2067200100040 CORRECTION .FOR DEAD TIME OF SPECTROMETER,SPECTROMETER 2067200100041 EFFICIENCY,SELF-ABSORPTION IN THE SAMPLE,ABUNDANCE 2067200100042 OF THE MEASURED GAMMA-TRANSITION,DECAY DURING 2067200100043 COUNTING TIME,CHANGE IN NEUTRON FLUX DURING 2067200100044 IRRADIATION. 2067200100045 ERR-ANALYS .UNCERTAINTIES ARISE FROM THE EFFICIENCY 2067200100046 DETERMINATION OF THE GE(LI)-SPECTROMETER,THE DEAD 2067200100047 TIME OF THE ELECTRONIC EQUIPMENT AND THE PEAK 2067200100048 ANALYSIS OF THE FISSION SPECTRA FOR THE 97-ZR 2067200100049 STANDARD. 2067200100050 .THE OTHER MAIN UNCERTAINTY ARISES FROM THE 2067200100051 LITERATURE VALUE OF THE ELECTRON-CAPTURE/BETA-MINUS 2067200100052 BRANCHING RATIO OF 1.05+-0.17(SEE J.E.GINDLER AND R. 2067200100053 K.SKJOBLOM,J.INORG.NUCL.CHEM.,12,8(1959)). 2067200100054 .THE STATISTICAL ERROR FOR ALPHA-COUNTING DID NOT 2067200100055 EXCEED 1.4PC. 2067200100056 ENDBIB 54 0 2067200100057 NOCOMMON 0 0 2067200100058 ENDSUBENT 57 0 2067200199999 SUBENT 20672002 19840127 00002067200200001 BIB 4 12 2067200200002 REACTION (93-NP-237(N,2N)93-NP-236-M,,SIG) 2067200200003 HALF-LIFE (HL,93-NP-236-M1) ONLY THE NP-236 ISOMER WITH A 2067200200004 HALFLIFE OF 22H WAS CONSIDERED IN THIS EXPERIMENT. 2067200200005 .VALUE TAKEN FROM LITERATURE BY AUTHOR. 2067200200006 COMMENT .THE QUOTED DATA REPRESENT, WHAT THE AUTHORS CALL 2067200200007 THEIR BEST CHOICE OUT OF FOUR DIFFERENT 2067200200008 DETERMINATIONS(2 DIFFERENT DECAY REACTIONS(SEE 2067200200009 METHOD) AND 2 DIFFERENT STANDARDS (SEE STANDARD). 2067200200010 .THE ONE PRESENTED IS DERIVED FROM THE ALPHA-COUNTING 2067200200011 METHOD IN CONNECTION WITH THE 27AL-STANDARD. 2067200200012 HISTORY (761027C) 2067200200013 (770504E) 2067200200014 ENDBIB 12 0 2067200200015 NOCOMMON 0 0 2067200200016 DATA 5 1 2067200200017 EN EN-ERR DATA DATA-ERR HL 2067200200018 MEV MEV MB MB HR 2067200200019 1.5000E+01 1.0000E+00 2.4700E+02 2.2000E+01 2.2000E+01 2067200200020 ENDDATA 3 0 2067200200021 ENDSUBENT 20 0 2067200299999 ENDENTRY 2 0 2067299999999