ENTRY 22885 20160920 22542288500000001 SUBENT 22885001 20160920 22542288500100001 BIB 18 77 2288500100002 TITLE .Quasistellar spectrum for neutron activation 2288500100003 measurements at kT=5 keV 2288500100004 AUTHOR (M.Heil, S.Dababneh, A.Juseviciute, F.Kaeppeler,R.Plag,2288500100005 R.Reifarth, S.O'Brien) 2288500100006 INSTITUTE (2GERKFK) Heil,Dababneh,Juseviciute,Kaeppeler,Plag 2288500100007 (1USALAS) Reifarth 2288500100008 (1USANOT) O'Brien 2288500100009 REFERENCE (J,PR/C,71,025803,200502) 2288500100010 (J,NP/A,758,529C,2005) MACS prelim. value . 2288500100011 FACILITY (VDG,2GERKFK) 3.7-MV Van de Graaff accelerator, 2288500100012 repetition rate 500 kHz, pulse width 1 ns, average 2288500100013 proton flux - 6 micro-Amp. 2288500100014 MONITOR ((MONIT)79-AU-197(N,G)79-AU-198-G,,SIG,,MXW) 2288500100015 At kT=30keV. 2288500100016 With normalization factor 0.954 the MACS =2028 mb at 2288500100017 kT=51.1 keV - see ASSUM in Subent 002. 2288500100018 MONIT-REF (22099001,W.Ratynski+,J,PR/C,37,595,1988) 2288500100019 DECAY-MON (79-AU-198-G,2.69517D,DG,411.80,0.9558) 2288500100020 2.69517+-0.00021 d, 95.58+-0.12 % . 2288500100021 INC-SOURCE . 8-O-18(P,N)9-F-18 reaction, 2288500100022 0.2-mm-thick tantalum disk with an oxide layer of 2288500100023 2.E-6 m thickness, with 95% in O-18 enrichment, 2288500100024 glued onto 1 mm thick water cooled copper backing. 2288500100025 Proton energy was 2582 keV, 12 keV above O-18(P,N) 2288500100026 reaction threshold 2574 keV 2288500100027 INC-SPECT .Quasi-Maxwellian neutron energy spectrum with 2288500100028 temperature kT=5.1 +- 0.1 keV 2288500100029 REL-REF (O,O1962002,M.Heil+,J,PR/C,71,025803,2005) 2288500100030 Neutron spectrum from O-18(P,N)F-18 reaction. 2288500100031 (I,,S.Dababneh+,J,NIM/A,517,230,2004) 2288500100032 Spectrometer details. 2288500100033 (O,23046001,M.Heil+,J,NP/A,758,529C,2005) Lu data 2288500100034 (O,23303001,M.Heil+,J,NP/A,758,529C,2005) La data 2288500100035 METHOD (ACTIV) Activation time - 172, 181, 212, 196 min. 2288500100036 (TOF) For neutron spectrum determination 2288500100037 DETECTOR (HPGE) Two Clover-type High Purity Ge detectors, each 2288500100038 of four independent n-type Ge crystal in common 2288500100039 cryostat. 2288500100040 (GLASD) 1.Movable Li-6 glass detector for neutron 2288500100041 angular distribution from 0 to 80 in steps 10 deg. 2288500100042 2. Li-6/ZnS detector as stationary neutron monitor, 2288500100043 detector positioned 300 mm from target at angle 2288500100044 40 deg. 2288500100045 3.Stationary Li-6 glass detector mounted at angle 2288500100046 120 deg.,at distance 222 mm for measuring g-ray 2288500100047 background. 2288500100048 SAMPLE .Barium carbonate Ba-C-O3 powder as pressed pellets of 2288500100049 20 mm diameter,1.5 mm thickness, enclosed in 2288500100050 0.1-mm-thick aluminum cans. Ba-138 enrichment is 2288500100051 98.04%. Pellets were sandwiched between two 0.06 mm 2288500100052 thick gold foils of typically 160 mg mass. 2288500100053 Placed 4.7 mm in front of neutron production target. 2288500100054 Ba sample mass - 1520.1 mg for Ba-1 sample, 2288500100055 and - 1474.4 mg for Ba-2 sample 2288500100056 CORRECTION .Corrections were made for decay of activated nuclei 2288500100057 flux during irradiation, including variations in 2288500100058 neutron flux. For self-absorption 2288500100059 ERR-ANALYS Sources of uncertainty. 2288500100060 (ERR-1,,0.1) Uncertainty of number of Ba sample atoms 2288500100061 (ERR-2,,0.1) Uncertainty of number of Au sample atoms 2288500100062 (ERR-3) Uncertainty of gamma-ray intensity for Au 2288500100063 (ERR-4) Uncertainty of gamma-ray intensity for Ba-138 2288500100064 (ERR-5,,0.1) Uncertainty of time factors for Au 2288500100065 (ERR-6,,0.1) Uncertainty of time factors for Ba 2288500100066 (ERR-7,,0.1) Uncertainty of summing effects for Au 2288500100067 (ERR-8,,0.1) Uncertainty of summing effects for Ba 2288500100068 (ERR-9) Uncertainty of detector efficiency for Au 2288500100069 (ERR-10) Uncertainty of detector efficiency for Ba 2288500100070 (MONIT-ERR) Monitor CS uncertainty - 2.5%. 2288500100071 COMMENT This work was partly supported by the Joint Institute 2288500100072 for Nuclear Astrophysics (JINA) through NSF Grants 2288500100073 Nos. PHY-0072711 and PHY-0228206. 2288500100074 HISTORY (20060125C) SM/MM 2288500100075 (20160920A) M.M. Ref. J,NPA,758,529C,2005 was added. 2288500100076 BIB and COMMON information was updated. 2288500100077 ERR-ANALYS was corrected according to new rules. 2288500100078 Ref. NIM/A,517,230,2004 was moved in REL-REF. 2288500100079 ENDBIB 77 0 2288500100080 COMMON 9 6 2288500100081 KT KT-ERR KT-NRM MONIT MONIT-ERR ERR-3 2288500100082 ERR-4 ERR-9 ERR-10 2288500100083 KEV KEV KEV MB MB PER-CENT 2288500100084 PER-CENT PER-CENT PER-CENT 2288500100085 5.1 0.1 30. 582. 9. 0.1 2288500100086 1.0 1.5 1.5 2288500100087 ENDCOMMON 6 0 2288500100088 ENDSUBENT 87 0 2288500199999 SUBENT 22885002 20160920 22542288500200001 BIB 7 26 2288500200002 REACTION 1(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 2288500200003 2(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 2288500200004 3(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 2288500200005 4(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 2288500200006 DECAY-DATA (56-BA-139,83.06MIN,DG,165.86,0.2376) 2288500200007 ANALYSIS 1.Ba-1 sample, activation time 172 min, neutron flux 2288500200008 in front of Au foil - 0.533E9 n/cm2/sec 2288500200009 in the rear of Au foil - 0.395E9 n/cm2/sec . 2288500200010 2.Ba-1 sample, activation time 181 min, neutron flux 2288500200011 in front of Au foil - 1.265E9 n/cm2/sec 2288500200012 in the rear of Au foil - 0.920E9 n/cm2/sec . 2288500200013 3.Ba-2 sample, activation time 212 min, neutron flux 2288500200014 in front of Au foil - 0.388E9 n/cm2/sec 2288500200015 in the rear of Au foil - 0.294E9 n/cm2/sec . 2288500200016 4.Ba-2 sample, activation time 196 min, neutron flux 2288500200017 in front of Au foil - 1.413E9 n/cm2/sec 2288500200018 in the rear of Au foil - 1.018E9 n/cm2/sec . 2288500200019 ASSUMED (ASSUM,79-AU-197(N,G)79-AU-198,,SIG,,MXW) Averaged 2288500200020 /v(thermal) at kT= 5.1 keV obtained from 2288500200021 ENDF/B-VI by normalizing to the value of 582 +- 9 mb 2288500200022 for KT = 30 keV 2288500200023 ERR-ANALYS (ERR-SYS) Systematic error 2288500200024 (ERR-S) Stat. error for specific barium sample 2288500200025 STATUS (TABLE) Table V of PR/C,71,025803,2005. Initial exp. 2288500200026 values. 2288500200027 HISTORY (20160920A) M.M. RAW was deleted. 2288500200028 ENDBIB 26 0 2288500200029 COMMON 4 3 2288500200030 ASSUM ASSUM-ERR ERR-HL ERR-IDD 2288500200031 MB MB MIN NO-DIM 2288500200032 2028. 50. 0.28 0.0025 2288500200033 ENDCOMMON 3 0 2288500200034 DATA 12 1 22288500200035 DATA 1ERR-S 1ERR-SYS 1DATA 2ERR-S 2ERR-SYS 42288500200036 DATA 3ERR-S 3ERR-SYS 3DATA 4ERR-S 4ERR-SYS 2288500200037 MB PER-CENT PER-CENT MB PER-CENT PER-CENT 2288500200038 MB PER-CENT PER-CENT MB PER-CENT PER-CENT 2288500200039 11.4 6.4 5.0 12.8 4.6 4.4 2288500200040 14.8 8.1 4.7 12.9 3.0 4.4 2288500200041 ENDDATA 6 0 2288500200042 ENDSUBENT 41 0 2288500299999 SUBENT 22885003 20160920 22542288500300001 BIB 5 14 2288500300002 REACTION (56-BA-138(N,G)56-BA-139,,SIG,,MXW,DERIV) Averaged 2288500300003 MACS - /V(thermal) 2288500300004 REL-REF (A,,H.Beer+,J,AJ,474,843,1997) 13.6+-0.5 mb 2288500300005 ANALYSIS .Obtained by averaging from data of SAN 002 2288500300006 ERR-ANALYS (ERR-T) Total uncertainty 3.8% . 2288500300007 (ERR-13,,,U) Counting statistics after combining the 2288500300008 data of four runs - for Ba. 2288500300009 (ERR-11,,,U) Counting statistics after combining the 2288500300010 data of four runs - for gold . 2288500300011 (ERR-12) Divergence of neutron flux after combining the2288500300012 data of four runs. 2288500300013 STATUS (TABLE) Text, p.025803-5 of PR/C,71,025803,2005. 2288500300014 = Text, p.532c of NP/A,758,529C,2005 . 2288500300015 (DEP,22885002) Directly measured data. 2288500300016 ENDBIB 14 0 2288500300017 NOCOMMON 0 0 2288500300018 DATA 5 1 2288500300019 DATA ERR-T ERR-13 ERR-11 ERR-12 2288500300020 MB MB PER-CENT PER-CENT PER-CENT 2288500300021 13.0 0.5 3.0 0.5 1.4 2288500300022 ENDDATA 3 0 2288500300023 ENDSUBENT 22 0 2288500399999 ENDENTRY 3 0 2288599999999