ENTRY 13672 20160804 14211367200000001 SUBENT 13672001 20160804 14211367200100001 BIB 13 33 1367200100002 INSTITUTE (1USALAS) 1367200100003 REFERENCE (J,NSE,128,270,199803) 1367200100004 (J,ANS,76,361,199706) 1367200100005 AUTHOR (D.Loaiza,G.Brunson,R.Sanchez,K.Butterfield) 1367200100006 TITLE Measurement of Absolute Delayed Neutron Yield and Group1367200100007 Constants for the Fast Fission of 235U and 237Np 1367200100008 FACILITY (CRASS,1USALAS) Godiva IV burst assembly 1367200100009 INC-SOURCE (REAC) Reactor spectrum passed through cadmium, Boral, 1367200100010 and borated polyethylene to absorb thermal neutrons. 1367200100011 INC-SPECT Fission neutrons. 1367200100012 METHOD (PLSED) Die-away curve obtained and fitted with 1367200100013 Levenberg-Marquardt nonlinear least-squares routine. 1367200100014 Decay constants and group abundances measured with 1367200100015 instantaneous and infinite (compared to shortest and 1367200100016 longest delayed-neutron periods, respectively), and 1367200100017 unfolded into 6 neutron groups. 1367200100018 DETECTOR Well counter consisting of 20 3He tubes embedded in 1367200100019 polyethylene, heavily shielded to reduce background. 1367200100020 CORRECTION Delayed-neutron activity corrected for the time- 1367200100021 dependent neutron background (0.27%) and dead time 1367200100022 (<2%). 1367200100023 ERR-ANALYS (DATA-ERR) Systematic uncertainty. 1367200100024 STATUS (TABLE) Data taken from Nucl.Sci.Eng., Tables I and II.1367200100025 (APRVD) D. Loaiza, 1997/8/12. No reply received to 1367200100026 author proof after 1999 update. 1367200100027 HISTORY (19970630C) 1367200100028 (19980812A) Updated to new codes. 1367200100029 (19990812A) Updated to new reference, absolute data 1367200100030 added. 1367200100031 (20021204A) Obsolete data heading replaced. 1367200100032 (20160728A) OS. STATUS updated, SAMPLE updated in 1367200100033 subs.2 and 3, monitor decay information in subs.3,5 1367200100034 corrected 1367200100035 ENDBIB 33 0 1367200100036 COMMON 1 3 1367200100037 EN-DUMMY 1367200100038 MEV 1367200100039 1.4 1367200100040 ENDCOMMON 3 0 1367200100041 ENDSUBENT 40 0 1367200199999 SUBENT 13672002 20160804 14211367200200001 BIB 3 4 1367200200002 REACTION (92-U-235(N,F),DL,NU,,FST) 1367200200003 SAMPLE (92-U-235,ENR=0.93) 3-gram metal sample, 93% enriched 1367200200004 235U. 1367200200005 CORRECTION Corrected for sample impurities. 1367200200006 ENDBIB 4 0 1367200200007 NOCOMMON 0 0 1367200200008 DATA 2 1 1367200200009 DATA DATA-ERR 1367200200010 PRT/FIS PRT/FIS 1367200200011 0.0163 0.0008 1367200200012 ENDDATA 3 0 1367200200013 ENDSUBENT 12 0 1367200299999 SUBENT 13672003 20160804 14211367200300001 BIB 5 10 1367200300002 REACTION 1((92-U-235(N,F),DL/GRP,NU,,FST)/ 1367200300003 (92-U-235(N,F),DL,NU,,FST)) 1367200300004 2(92-U-235(N,F),DL/GRP,NU,,FST) 1367200300005 SAMPLE (92-U-235,ENR=0.93) 3-gram metal sample, 93% enriched 1367200300006 235U. 1367200300007 MONITOR 2(92-U-235(N,F)57-LA-140,CUM,FY) 1367200300008 La-140 in equilibrium with 140Ba (12.9 d) after 1367200300009 13 days 1367200300010 CORRECTION Corrected for sample impurities. 1367200300011 HISTORY (20160728A) DECAY-MON replaced by free text 1367200300012 ENDBIB 10 0 1367200300013 NOCOMMON 0 0 1367200300014 DATA 5 6 1367200300015 DCNST DCNST-ERR DATA 1DATA-ERR 1DATA 2 1367200300016 1/SEC 1/SEC NO-DIM NO-DIM PRT/FIS 1367200300017 0.0127 0.0001 0.0395 0.001 0.000644 1367200300018 0.0315 0.0004 0.235 0.005 0.00383 1367200300019 0.117 0.0064 0.207 0.008 0.00337 1367200300020 0.311 0.0197 0.381 0.011 0.00621 1367200300021 1.37 0.0514 0.114 0.005 0.00186 1367200300022 3.83 0.1138 0.0235 0.001 0.000383 1367200300023 ENDDATA 8 0 1367200300024 ENDSUBENT 23 0 1367200399999 SUBENT 13672004 20021204 00001367200400001 BIB 2 2 1367200400002 REACTION (93-NP-237(N,F),DL,NU,,FST) 1367200400003 SAMPLE 3.5-gram metal sample, 99% 237Np. 1367200400004 ENDBIB 2 0 1367200400005 NOCOMMON 0 0 1367200400006 DATA 2 1 1367200400007 DATA DATA-ERR 1367200400008 PRT/FIS PRT/FIS 1367200400009 0.0126 0.0007 1367200400010 ENDDATA 3 0 1367200400011 ENDSUBENT 10 0 1367200499999 SUBENT 13672005 20160804 14211367200500001 BIB 4 8 1367200500002 REACTION 1((93-NP-237(N,F),DL/GRP,NU,,FST)/ 1367200500003 (93-NP-237(N,F),DL,NU,,FST)) 1367200500004 2(93-NP-237(N,F),DL/GRP,NU,,FST) 1367200500005 SAMPLE 3.5-gram metal sample, 99% 237Np. 1367200500006 MONITOR 2(92-U-235(N,F)57-LA-140,CUM,FY) 1367200500007 La-140 in equilibrium with 140Ba (12.9 d) after 1367200500008 13 days 1367200500009 HISTORY (20160728A) DECAY-MON replaced by free text 1367200500010 ENDBIB 8 0 1367200500011 NOCOMMON 0 0 1367200500012 DATA 5 6 1367200500013 DCNST DCNST-ERR DATA 1DATA-ERR 1DATA 2 1367200500014 1/SEC 1/SEC NO-DIM NO-DIM PRT/FIS 1367200500015 0.0123 0.0009 0.032 0.003 0.000403 1367200500016 0.0284 0.0005 0.238 0.006 0.00299 1367200500017 0.0971 0.007 0.175 0.008 0.00221 1367200500018 0.296 0.014 0.360 0.017 0.00454 1367200500019 0.914 0.058 0.150 0.014 0.00189 1367200500020 3.2 0.13 0.045 0.006 0.000567 1367200500021 ENDDATA 8 0 1367200500022 ENDSUBENT 21 0 1367200599999 ENDENTRY 5 0 1367299999999