ENTRY 30527 20090312 31373052700000001 SUBENT 30527001 20090312 31373052700100001 BIB 15 39 3052700100002 TITLE - The reaction Si-28(n,alfa+p)Na-24 with reactor 3052700100003 neutrons. - 3052700100004 AUTHOR (S.Niese) 3052700100005 INSTITUTE (3DDRZFI) 3052700100006 REFERENCE (J,IP,25,(1),28,1989) Supersedes data of previous ref. 3052700100007 (J,JRC,38,37,1977) 3052700100008 (P,ZFK-340,197709) Short note. 3052700100009 SAMPLE Natural silicon 3052700100010 MONITOR Sodium and aluminum standards were irradiated together 3052700100011 with the silicon samples. 3052700100012 FACILITY (REAC,3DDRROS) Rossendorf Research Reactor 3052700100013 Static generator - for 14MeV neutrons. 3052700100014 INC-SOURCE (REAC) 3052700100015 (D-T) 3052700100016 METHOD (ACTIV). After irradiation of the silicon samples, the 3052700100017 contents of Na-24 are measured. 3052700100018 Na-24 can be produced either by impurities, i.e.: 3052700100019 Na-23(n,g) (with thermal neutrons), or 3052700100020 Al-27(n,a) (with fast neutrons) 3052700100021 or by the reaction 3052700100022 Si-28(n,ap), which has a q-value of 14.7 MeV. 3052700100023 DETECTOR (GELI).60 cm3. 3052700100024 ANALYSIS Cd-wrapped Si irradiated in the reactor core gave 3052700100025 higher amounts of Na-24 than Si irradiated in the 14MeV3052700100026 neutron generator. Because of the high q-value, it was 3052700100027 assumed that the Si-28(n,ap)reaction could not take 3052700100028 place in the 14MeV neutron beam. Therefore, the 3052700100029 difference of Na-24 produced in the fission spectrum of3052700100030 the reactor and in the 14MeV beam was attributed to the3052700100031 Si-28(n,ap) reaction. 3052700100032 CORRECTION For the Na-23(n,g) reaction with fast neutrons 3052700100033 ERR-ANALYS (DATA-ERR) Standard deviation of 15 measurements 3052700100034 STATUS (TABLE) Data are from 3052700100035 J,Isotopenpraxis, vol.25,(1),pp.28-30(1989). 3052700100036 HISTORY (19791221C) TL. 3052700100037 (19921120A) HW.- Reference added and status altered in 3052700100038 subent 001, data altered in subent 002. 3052700100039 (20090312A) SD:Updated to new date formats,lower case, 3052700100040 and formal corrections. 3052700100041 ENDBIB 39 0 3052700100042 NOCOMMON 0 0 3052700100043 ENDSUBENT 42 0 3052700199999 SUBENT 30527002 20090312 31373052700200001 BIB 4 8 3052700200002 REACTION (14-SI-28(N,P+A)11-NA-24,,SIG,,SPA) 3052700200003 INC-SPECT Cd-wrapped sample in reactor core with: 3052700200004 thermal flux = 5.0 x 10**13 n/cm2*sec 3052700200005 fission flux = 1.2 x 10**13 n/cm2*sec 3052700200006 COMMENT -Note that the cross-section value is an average over 3052700200007 the whole fission spectrum, although the threshold 3052700200008 energy of the considered reaction is 14.7 MeV.- 3052700200009 HISTORY (19921120A) HW.- Data altered. 3052700200010 ENDBIB 8 0 3052700200011 COMMON 1 3 3052700200012 EN-DUMMY 3052700200013 MEV 3052700200014 2. 3052700200015 ENDCOMMON 3 0 3052700200016 DATA 2 1 3052700200017 DATA DATA-ERR 3052700200018 NB NB 3052700200019 2.1000E+00 4.0000E-01 3052700200020 ENDDATA 3 0 3052700200021 ENDSUBENT 20 0 3052700299999 ENDENTRY 2 0 3052799999999