ENTRY 22885 20160920 225422885 0 1 SUBENT 22885001 20160920 225422885 1 1 BIB 18 77 22885 1 2 TITLE .Quasistellar spectrum for neutron activation 22885 1 3 measurements at kT=5 keV 22885 1 4 AUTHOR (M.Heil, S.Dababneh, A.Juseviciute, F.Kaeppeler,R.Plag,22885 1 5 R.Reifarth, S.O'Brien) 22885 1 6 INSTITUTE (2GERKFK) Heil,Dababneh,Juseviciute,Kaeppeler,Plag 22885 1 7 (1USALAS) Reifarth 22885 1 8 (1USANOT) O'Brien 22885 1 9 REFERENCE (J,PR/C,71,025803,200502) 22885 1 10 (J,NP/A,758,529C,2005) MACS prelim. value . 22885 1 11 FACILITY (VDG,2GERKFK) 3.7-MV Van de Graaff accelerator, 22885 1 12 repetition rate 500 kHz, pulse width 1 ns, average 22885 1 13 proton flux - 6 micro-Amp. 22885 1 14 MONITOR ((MONIT)79-AU-197(N,G)79-AU-198-G,,SIG,,MXW) 22885 1 15 At kT=30keV. 22885 1 16 With normalization factor 0.954 the MACS =2028 mb at 22885 1 17 kT=51.1 keV - see ASSUM in Subent 002. 22885 1 18 MONIT-REF (22099001,W.Ratynski+,J,PR/C,37,595,1988) 22885 1 19 DECAY-MON (79-AU-198-G,2.69517D,DG,411.80,0.9558) 22885 1 20 2.69517+-0.00021 d, 95.58+-0.12 % . 22885 1 21 INC-SOURCE . 8-O-18(P,N)9-F-18 reaction, 22885 1 22 0.2-mm-thick tantalum disk with an oxide layer of 22885 1 23 2.E-6 m thickness, with 95% in O-18 enrichment, 22885 1 24 glued onto 1 mm thick water cooled copper backing. 22885 1 25 Proton energy was 2582 keV, 12 keV above O-18(P,N) 22885 1 26 reaction threshold 2574 keV 22885 1 27 INC-SPECT .Quasi-Maxwellian neutron energy spectrum with 22885 1 28 temperature kT=5.1 +- 0.1 keV 22885 1 29 REL-REF (O,O1962002,M.Heil+,J,PR/C,71,025803,2005) 22885 1 30 Neutron spectrum from O-18(P,N)F-18 reaction. 22885 1 31 (I,,S.Dababneh+,J,NIM/A,517,230,2004) 22885 1 32 Spectrometer details. 22885 1 33 (O,23046001,M.Heil+,J,NP/A,758,529C,2005) Lu data 22885 1 34 (O,23303001,M.Heil+,J,NP/A,758,529C,2005) La data 22885 1 35 METHOD (ACTIV) Activation time - 172, 181, 212, 196 min. 22885 1 36 (TOF) For neutron spectrum determination 22885 1 37 DETECTOR (HPGE) Two Clover-type High Purity Ge detectors, each 22885 1 38 of four independent n-type Ge crystal in common 22885 1 39 cryostat. 22885 1 40 (GLASD) 1.Movable Li-6 glass detector for neutron 22885 1 41 angular distribution from 0 to 80 in steps 10 deg. 22885 1 42 2. Li-6/ZnS detector as stationary neutron monitor, 22885 1 43 detector positioned 300 mm from target at angle 22885 1 44 40 deg. 22885 1 45 3.Stationary Li-6 glass detector mounted at angle 22885 1 46 120 deg.,at distance 222 mm for measuring g-ray 22885 1 47 background. 22885 1 48 SAMPLE .Barium carbonate Ba-C-O3 powder as pressed pellets of 22885 1 49 20 mm diameter,1.5 mm thickness, enclosed in 22885 1 50 0.1-mm-thick aluminum cans. Ba-138 enrichment is 22885 1 51 98.04%. Pellets were sandwiched between two 0.06 mm 22885 1 52 thick gold foils of typically 160 mg mass. 22885 1 53 Placed 4.7 mm in front of neutron production target. 22885 1 54 Ba sample mass - 1520.1 mg for Ba-1 sample, 22885 1 55 and - 1474.4 mg for Ba-2 sample 22885 1 56 CORRECTION .Corrections were made for decay of activated nuclei 22885 1 57 flux during irradiation, including variations in 22885 1 58 neutron flux. For self-absorption 22885 1 59 ERR-ANALYS Sources of uncertainty. 22885 1 60 (ERR-1,,0.1) Uncertainty of number of Ba sample atoms 22885 1 61 (ERR-2,,0.1) Uncertainty of number of Au sample atoms 22885 1 62 (ERR-3) Uncertainty of gamma-ray intensity for Au 22885 1 63 (ERR-4) Uncertainty of gamma-ray intensity for Ba-138 22885 1 64 (ERR-5,,0.1) Uncertainty of time factors for Au 22885 1 65 (ERR-6,,0.1) Uncertainty of time factors for Ba 22885 1 66 (ERR-7,,0.1) Uncertainty of summing effects for Au 22885 1 67 (ERR-8,,0.1) Uncertainty of summing effects for Ba 22885 1 68 (ERR-9) Uncertainty of detector efficiency for Au 22885 1 69 (ERR-10) Uncertainty of detector efficiency for Ba 22885 1 70 (MONIT-ERR) Monitor CS uncertainty - 2.5%. 22885 1 71 COMMENT This work was partly supported by the Joint Institute 22885 1 72 for Nuclear Astrophysics (JINA) through NSF Grants 22885 1 73 Nos. PHY-0072711 and PHY-0228206. 22885 1 74 HISTORY (20060125C) SM/MM 22885 1 75 (20160920A) M.M. Ref. J,NPA,758,529C,2005 was added. 22885 1 76 BIB and COMMON information was updated. 22885 1 77 ERR-ANALYS was corrected according to new rules. 22885 1 78 Ref. NIM/A,517,230,2004 was moved in REL-REF. 22885 1 79 ENDBIB 77 0 22885 1 80 COMMON 9 6 22885 1 81 KT KT-ERR KT-NRM MONIT MONIT-ERR ERR-3 22885 1 82 ERR-4 ERR-9 ERR-10 22885 1 83 KEV KEV KEV MB MB PER-CENT 22885 1 84 PER-CENT PER-CENT PER-CENT 22885 1 85 5.1 0.1 30. 582. 9. 0.1 22885 1 86 1.0 1.5 1.5 22885 1 87 ENDCOMMON 6 0 22885 1 88 ENDSUBENT 87 0 22885 199999 SUBENT 22885002 20160920 225422885 2 1 BIB 7 26 22885 2 2 REACTION 1(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 22885 2 3 2(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 22885 2 4 3(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 22885 2 5 4(56-BA-138(N,G)56-BA-139,,SIG,,MXW) 22885 2 6 DECAY-DATA (56-BA-139,83.06MIN,DG,165.86,0.2376) 22885 2 7 ANALYSIS 1.Ba-1 sample, activation time 172 min, neutron flux 22885 2 8 in front of Au foil - 0.533E9 n/cm2/sec 22885 2 9 in the rear of Au foil - 0.395E9 n/cm2/sec . 22885 2 10 2.Ba-1 sample, activation time 181 min, neutron flux 22885 2 11 in front of Au foil - 1.265E9 n/cm2/sec 22885 2 12 in the rear of Au foil - 0.920E9 n/cm2/sec . 22885 2 13 3.Ba-2 sample, activation time 212 min, neutron flux 22885 2 14 in front of Au foil - 0.388E9 n/cm2/sec 22885 2 15 in the rear of Au foil - 0.294E9 n/cm2/sec . 22885 2 16 4.Ba-2 sample, activation time 196 min, neutron flux 22885 2 17 in front of Au foil - 1.413E9 n/cm2/sec 22885 2 18 in the rear of Au foil - 1.018E9 n/cm2/sec . 22885 2 19 ASSUMED (ASSUM,79-AU-197(N,G)79-AU-198,,SIG,,MXW) Averaged 22885 2 20 /v(thermal) at kT= 5.1 keV obtained from 22885 2 21 ENDF/B-VI by normalizing to the value of 582 +- 9 mb 22885 2 22 for KT = 30 keV 22885 2 23 ERR-ANALYS (ERR-SYS) Systematic error 22885 2 24 (ERR-S) Stat. error for specific barium sample 22885 2 25 STATUS (TABLE) Table V of PR/C,71,025803,2005. Initial exp. 22885 2 26 values. 22885 2 27 HISTORY (20160920A) M.M. RAW was deleted. 22885 2 28 ENDBIB 26 0 22885 2 29 COMMON 4 3 22885 2 30 ASSUM ASSUM-ERR ERR-HL ERR-IDD 22885 2 31 MB MB MIN NO-DIM 22885 2 32 2028. 50. 0.28 0.0025 22885 2 33 ENDCOMMON 3 0 22885 2 34 DATA 12 1 222885 2 35 DATA 1ERR-S 1ERR-SYS 1DATA 2ERR-S 2ERR-SYS 422885 2 36 DATA 3ERR-S 3ERR-SYS 3DATA 4ERR-S 4ERR-SYS 22885 2 37 MB PER-CENT PER-CENT MB PER-CENT PER-CENT 22885 2 38 MB PER-CENT PER-CENT MB PER-CENT PER-CENT 22885 2 39 11.4 6.4 5.0 12.8 4.6 4.4 22885 2 40 14.8 8.1 4.7 12.9 3.0 4.4 22885 2 41 ENDDATA 6 0 22885 2 42 ENDSUBENT 41 0 22885 299999 SUBENT 22885003 20160920 225422885 3 1 BIB 5 14 22885 3 2 REACTION (56-BA-138(N,G)56-BA-139,,SIG,,MXW,DERIV) Averaged 22885 3 3 MACS - /V(thermal) 22885 3 4 REL-REF (A,,H.Beer+,J,AJ,474,843,1997) 13.6+-0.5 mb 22885 3 5 ANALYSIS .Obtained by averaging from data of SAN 002 22885 3 6 ERR-ANALYS (ERR-T) Total uncertainty 3.8% . 22885 3 7 (ERR-13,,,U) Counting statistics after combining the 22885 3 8 data of four runs - for Ba. 22885 3 9 (ERR-11,,,U) Counting statistics after combining the 22885 3 10 data of four runs - for gold . 22885 3 11 (ERR-12) Divergence of neutron flux after combining the22885 3 12 data of four runs. 22885 3 13 STATUS (TABLE) Text, p.025803-5 of PR/C,71,025803,2005. 22885 3 14 = Text, p.532c of NP/A,758,529C,2005 . 22885 3 15 (DEP,22885002) Directly measured data. 22885 3 16 ENDBIB 14 0 22885 3 17 NOCOMMON 0 0 22885 3 18 DATA 5 1 22885 3 19 DATA ERR-T ERR-13 ERR-11 ERR-12 22885 3 20 MB MB PER-CENT PER-CENT PER-CENT 22885 3 21 13.0 0.5 3.0 0.5 1.4 22885 3 22 ENDDATA 3 0 22885 3 23 ENDSUBENT 22 0 22885 399999 ENDENTRY 3 0 2288599999999