ENTRY 22401 20210908 23032240100000001 SUBENT 22401001 20210908 23032240100100001 BIB 14 44 2240100100002 TITLE The (n,gamma) cross section of Li-7 2240100100003 AUTHOR (M.Heil,F.Kaeppeler,M.Wiescher, A.Mengoni) 2240100100004 INSTITUTE (2GERKFK) M.Heil, F.Kaeppeler 2240100100005 (1USANOT) M.Wiescher 2240100100006 (2ITYBOL) A.Mengoni 2240100100007 (2JPNIPC) A.Mengoni 2240100100008 REFERENCE (J,AJ,507,997,1998) Final publication. Data Table. 2240100100009 Detailed analysis of uncertainties. 2240100100010 (C,97TRIEST,2,1618,199705) Data almost the same. 2240100100011 (R,INDC(GER)-0053,2021) Reaction ratio (Subent 004). 2240100100012 REL-REF (C,22171004,M.Wiescher+,J,AJ,344,464,1989) - 2240100100013 value of CS at 25 keV measured in Subent 22171.004 2240100100014 by ionization chamber was re-analyzed to be 57+-9 mu-b 2240100100015 - discrepancy was mainly due to miscalculation of the 2240100100016 total efficiency the ionization chamber; new analysis 2240100100017 of the activation with Li-glass detector of this Entry 2240100100018 was impossible,because the original data could no 2240100100019 longer be retrieved. 2240100100020 METHOD (ACTIV) 2240100100021 MONITOR (3-LI-6(N,T)2-HE-4,,SIG,,SPA) For neutron flux. 2240100100022 Obtained by folding the differential CS with the 2240100100023 experimental neutron spectrum. 2240100100024 PART-DET (A,T) they are for alpha and triton from 2240100100025 6Li(n,alpha)3H and alphas from 8Be decays 2240100100026 DECAY-DATA (3-LI-8,0.84SEC,B-) 2240100100027 (4-BE-8,,A,2140.) 2240100100028 RAD-DET (4-BE-8,A) 2240100100029 DETECTOR (IOCH) Gridded twin ionization chamber with argon- 2240100100030 methane gas at 4.5 bar constant pressure. Efficiency of2240100100031 alpha-particles detection 99+-1 % and energy resolution2240100100032 1.7% for 5.1 MeV were determined with calibrated 2240100100033 alpha-source. 2240100100034 SAMPLE Natural lithium fluoride Li-F layer of 210 mug/cm2 2240100100035 thickness, 36 mm diameter, evaporated on 20+-2 mug/cm2 2240100100036 C backing with a fine W mesh, with 88% transmission. 2240100100037 Li-6/Li-7 ratio was determined by mass spectroscopy 2240100100038 to be 0.082219+- (13%) . 2240100100039 ADD-RES (COMP) Direct radiative capture model calculations. 2240100100040 HISTORY (19980808C) + + Compiled by S.Maev + + 2240100100041 (20160427A) M.M. Upper -> lower case correction. Ref. 2240100100042 AJ,507,997,1998 was added. BIB information was updated.2240100100043 (20200803A) SD: Energy units corrected in Subent 003. 2240100100044 BIB updated. 2240100100045 (20210908A) SD: Entry updated. 2240100100046 ENDBIB 44 0 2240100100047 NOCOMMON 0 0 2240100100048 ENDSUBENT 47 0 2240100199999 SUBENT 22401002 20210908 23032240100200001 BIB 9 38 2240100200002 REACTION 1((3-LI-7(N,G)3-LI-8,,SIG,,SPA)/ 2240100200003 (3-LI-6(N,T)2-HE-4,,SIG,,SPA)) 2240100200004 2(3-LI-7(N,G)3-LI-8,,SIG,,SPA) 2240100200005 FACILITY (REAC,2GERMUN) FRM I reactor of Munich 2240100200006 INC-SOURCE (REAC) Neutron guide of FRM I reactor 2240100200007 INC-SPECT Spectrum of average energy 5 meV, ranging from 1 meV 2240100200008 up to 20 meV . 2240100200009 METHOD Activation cycles. Irradiation time 2.180 s, waiting 2240100200010 time 0.009 s, measurement time 2.52 s. 6925 cycles. 2240100200011 Be-8 yield 2380, Li-6 yield 7688752 . 2240100200012 CORRECTION For self-absorption : factor for Li-6 - 0.95, 2240100200013 factor for Be-8 - 0.88. 2240100200014 For contribution from previous cycle - factor 0.9998 2240100200015 For fraction of the induced activity that had already 2240100200016 decayed during the irradiation - factor 0.464 2240100200017 For background obtained in a measurement with dummy 2240100200018 sample - < 1.5 %. 2240100200019 ERR-ANALYS (DATA-ERR) No information about source of uncertainty 2240100200020 (ERR-S) Statistical uncertainty (Be-8) 1.2% 2240100200021 (ERR-SYS) Systematic uncertainty includes: 2240100200022 (ERR-1) Uncertainty in irradiation time ( stat.) 0.7% 2240100200023 (ERR-2) Uncertainty in waiting time ( stat.) 33.% 2240100200024 (ERR-3) Uncertainty in counting time ( stat.) 0.6% 2240100200025 (ERR-4) Uncertainty of correction factor for 2240100200026 self-absorption for Li-6 2.% 2240100200027 (ERR-5) Uncertainty of correction factor for 2240100200028 self-absorption for Be-8 5.% 2240100200029 (MONIT-ERR) Monitor CS uncertainty 1% 2240100200030 (ERR-6) Statistical uncertainty (Li-6) 0.02% 2240100200031 STATUS (TABLE) Table 3 of Astrophys.J.,507(1998)997 - data, 2240100200032 system. and stat. uncert., 2240100200033 Table 2 - partial uncertainties. 2240100200034 Reaction ratio added from p.93 of INDC(GER)-0053.2240100200035 HISTORY (20160427A) M.M. SF8 was corrected AV -> SPA. 2240100200036 INC-SPECT, METHOD, ERR-ANALYS, CORRECTION, MONIT, 2240100200037 EN-MEAN were added. 2240100200038 (20210908A) SD: REACTION ratio added. 2240100200039 ERR-ANALYS, STATUS updated. 2240100200040 ENDBIB 38 0 2240100200041 COMMON 6 3 2240100200042 ERR-1 ERR-2 ERR-3 ERR-4 ERR-5 ERR-6 2240100200043 PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT 2240100200044 0.7 33. 0.6 2. 5. 0.02 2240100200045 ENDCOMMON 3 0 2240100200046 DATA 10 1 2240100200047 EN-MIN EN-MAX EN-MEAN DATA 1DATA-ERR 1DATA 22240100200048 ERR-S 2ERR-SYS 2MONIT 2MONIT-ERR 2 2240100200049 EV EV MILLI-EV NO-DIM NO-DIM B 2240100200050 PER-CENT PER-CENT B PER-CENT 2240100200051 0.0017 0.020 0.005 4.81E-05 0.28E-05 0.10192240100200052 2.0 5.6 2117. 1.0 2240100200053 ENDDATA 6 0 2240100200054 ENDSUBENT 53 0 2240100299999 SUBENT 22401003 20210908 23032240100300001 BIB 9 46 2240100300002 REACTION 1((3-LI-7(N,G)3-LI-8,,SIG,,SPA)/ 2240100300003 (3-LI-6(N,T)2-HE-4,,SIG,,SPA)) 2240100300004 2(3-LI-7(N,G)3-LI-8,,SIG,,SPA) 2240100300005 FACILITY (VDG,2GERKFK) 3.75 MV Van de Graaff Accelerator 2240100300006 INC-SOURCE (P-LI7) Proton energy 1912 keV. 2240100300007 INC-SPECT Angle-integrated neutron spectrum is well approximated2240100300008 with Maxwell-Boltzmann distribution for kT=25 keV. 2240100300009 Because sample was positioned as 35 mm distance, it did2240100300010 not cover the entire ( 120deg) neutron cone, resulting 2240100300011 in an effective neutron acceptance angle of 50 deg. 2240100300012 The resulting neutron spectrum was distorted, showing 2240100300013 a rather flat distribution ranging from 5 keV up to 2240100300014 110 keV, with an average value 54 keV. See Fig.2 in 2240100300015 AJ,507,997,1998 . 2240100300016 METHOD Activation cycles. Irradiation time 1.576 s, waiting 2240100300017 time 0.012 s, measurement time 2.238 s. 102506 cycles. 2240100300018 Be-8 yield 2380, Li-6 yield 7688752 . 2240100300019 CORRECTION For self-absorption : factor for Li-6 - 0.93, 2240100300020 factor for Be-8 - 0.83. 2240100300021 For contribution from previous cycle - factor 0.963 2240100300022 For fraction of the induced activity that had already 2240100300023 decayed during the irradiation - factor 0.620 2240100300024 For background obtained in a measurement with dummy 2240100300025 sample - <1.5%. 2240100300026 ERR-ANALYS (DATA-ERR) No information about source of uncertainty 2240100300027 (ERR-S) Statistical uncertainty (Be-8) 2.6% 2240100300028 (ERR-SYS) Systematic error includes: 2240100300029 (ERR-1) Uncertainty in irradiation time ( stat.) 1.% 2240100300030 (ERR-2) Uncertainty in waiting time ( stat.) 33.% 2240100300031 (ERR-3) Uncertainty in counting time ( stat.) 0.7% 2240100300032 (ERR-4) Uncertainty of correction factor for 2240100300033 self-absorption for Li-6 3.% 2240100300034 (ERR-5) Uncertainty of correction factor for 2240100300035 self-absorption for Be-8 6.% 2240100300036 (MONIT-ERR) Monitor CS uncertainty 3% 2240100300037 (ERR-6) Statistical uncertainty (Li-6) 0.04% 2240100300038 STATUS (TABLE) Table 3 of Astrophys.J.,507(1998)997 - data, 2240100300039 system. and stat. uncert., 2240100300040 Table 2 - partial uncertainties. 2240100300041 Reaction ratio added from p.92 of INDC(GER)-0053.2240100300042 HISTORY (20160427A) M.M. SF8 was corrected AV -> SPA. 2240100300043 INC-SPECT, METHOD, ERR-ANALYS, CORRECTION, MONIT, 2240100300044 EN-MEAN were added. 2240100300045 (20200803A) SD: EN-MAX: EV -> KEV. 2240100300046 (20210908A) SD: REACTION ratio added. 2240100300047 ERR-ANALYS, STATUS updated. 2240100300048 ENDBIB 46 0 2240100300049 COMMON 6 3 2240100300050 ERR-1 ERR-2 ERR-3 ERR-4 ERR-5 ERR-6 2240100300051 PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT 2240100300052 1. 33. 0.7 3. 6. 0.04 2240100300053 ENDCOMMON 3 0 2240100300054 DATA 10 1 2240100300055 EN-MIN EN-MAX EN-MEAN DATA 1DATA-ERR 1DATA 22240100300056 ERR-S 2ERR-SYS 2MONIT 2MONIT-ERR 2 2240100300057 KEV KEV KEV NO-DIM NO-DIM B 2240100300058 PER-CENT PER-CENT B PER-CENT 2240100300059 5.0 105. 54. 4.53E-05 0.32E-05 3.66E-052240100300060 2.6 6.5 0.808 3. 2240100300061 ENDDATA 6 0 2240100300062 ENDSUBENT 61 0 2240100399999 ENDENTRY 3 0 2240199999999