81SE 81AS B- DECAY 1974CH11,1975KR08 25NDS 202501
81SE H TYP=FUL$AUT=M. Shamsuzzoha Basunia$CIT=NDS 199, 271 (2025)$
81SE2 H CUT=1-Sep-2024$
81SE c Others: 1960Mo01, 1972De43, 1990Ru05.
81SE c 1974Ch11: {+81}As produced by {+82}Se(|g,p), Ge(Li) detectors
81SE2c (FWHM=1.6 keV at 574 keV for Ge(Li) used for E|g<1300); measured E|g,
81SE3c I|g, T{-1/2}.
81SE c 1975Kr08: {+81}As produced in {+233,235}U(thermal n,f) or
81SE2c {+82}Se(n,pn), Ge(Li) detectors, FWHM=2.1 to 2.8 keV at E|g=1332;
81SE3c measured E|g, I|g.
81SE c 1960Mo01: Measured T{-1/2} of {+81}As, |b endpoint energy.
81SE c 1972De43: {+81}As was obtained from {+81}Ge decay, the latter was
81SE2c produced from fast radiochemical separation at short time intervals
81SE3c from fission products in {+235}U(n,f). NaI(Tl) crystal. Reported
81SE4c partial level scheme.
81SE cB Measured average E|b=1600 {I30} (1990Ru05).
81SE cB IB Uncertainty shown excludes unknown (and possibly large)
81SE2cB uncertainty in I|g normalization. Consequently, log {Ift} values are
81SE3cB shown as approximate.
81SE cG Measured average E|g=2040 {I100} (1990Ru05).
81SE cG 1974Ch11 report additional |g rays whose I|g is very weak or
81SE2cG whose T{-1/2} differs somewhat from that for {+81}As(g.s.), as follows:
81SE3cG 744.6, 788.8, 910, 992.5, 998, 1050.5, 1352.6. Also, impurity lines
81SE4cG would have masked {+81}As lines with E|g|?400 or 264, were they
81SE5cG present.
81SE cG E,RI From 1974Ch11, except where otherwise noted.
81SE cG E(A),RI(A)$From 1975Kr08; absent in 1974Ch11.
81SE cG E(F) |g placement in 1974Ch11. However, E|g differs from the least
81SE2cG squares adjusted value by at least 5|s. At least one |g deexciting the
81SE3cG 3223 level is presumably misplaced.
81SE cG RI(E) Absolute I(468|g)|?20% deduced by 1972De43 based on measured
81SE2cG I(336|g, {+81}As), I(277|g, {+78}As) and I(336|g, {+81}As)/I(468|g,
81SE3cG {+81}Se)=0.83 {I5}, assuming I(277|g, {+78}As)=95% and an estimated
81SE4cG relative fission yield of 6.5 {I2} for {+81}Ge/{+78}Ge (1972De43).
81SE cG RI(G) 1975Kr08 report I|g=15 {I10} for a T{-1/2}=57 min 103|g
81SE2cG which grows into their As fraction with T{-1/2}=30 s {I10} (1974Ch11
81SE2cG do not report I(103|g) because the isomeric state was produced
81SE3cG directly via the (|g,n) reaction during their source preparation).
81SE4cG However, if I|b(103)<1.3% as required for log| {If{+1u}t}>8.5,
81SE5cG I(103|g)<2.7 is expected, assuming |a(103|g)=6.8.
81SE cG M,MR From Adopted Gammas.
81SE cL E From a least-squares fit to E|g.
81SE cL E(H) Level proposed by 1974Ch11. However, the two deexciting
81SE2cL E|g yield poor fit, differing by at least 5|s from the least-squares
81SE3cL adjusted value. E=3221.1 {I2} based on 3118|g alone and E=3224.2 {I2}
81SE4cL based on 2733|g alone. Evaluator adopts unweighted average (3222.7
81SE5cL {I16}) in preference to the least-squares adjusted value of 3222.75
81SE6cL {I17}.
81SE cL J,T From Adopted Levels.
81SE N 0.20 AP 1.0 1.0
81SE cN NR from %I(468|g)|?20% deduced in 1972De43. For details, see
81SE2cN comment on I|g(468|g).
81SE PN 3
81AS P 0 3/2- 33.3 S 10 3855.7 28
81AS cP QP$from 2021Wa16
81SE G 874.9 2 0.69 10
81SE L 0 1/2- 18.5 M 1
81SE B 65.7 AP 5.29 AP
81SES B EAV=1681.6 13
81SE cB E 3800 {I200} (1960Mo01 - from 3.8 MeV {I2}).
81SE cB IB from 100 - |SI{-|b} to excited states, assuming 0.65% {I65}
81SE2cB |b{+-} feeding of 7/2+, 102.86-keV level.
81SE L 102.86 137/2+ 57.28 M 2 M
81SE B 1.3 LT 8.5 GT 1U?
81SE cB IB$as required for log {If{+1u}t}>8.5 and expected I(103|g)<2.7
81SE2cB assuming |a(103|g)=6.8. See footnote for 103|g.
81SES B EAV=1632.4 13
81SE G 103.0 2 E3(+M4) 0.0056 LT 6.80 11 G
81SES G KC=5.30 8$LC=1.287 21$MC=0.201 4$NC+=0.01350 22
81SES G NC=0.01350 22
81SE cG E weighted average of 103.0 {I2} (1974Ch11) and 102.9 {I2}
81SE2cG (1975Kr08).
81SE L 467.66 11 3/2-
81SE B 17.89 AP 5.61 AP
81SES B EAV=1457.8 13
81SE G 467.7 2 100 E
81SE cG E weighted average of 467.6 {I2} (1974Ch11) and 467.8 {I2}
81SE2cG (1975Kr08).
81SE L 490.82 11 (5/2-)
81SE B 8.94 AP 5.90 AP
81SES B EAV=1446.7 13
81SE G 388.1 2 4.3 5 A
81SE G 491.2 2 42.5 5 (E2) 0.00291
81SE cG E weighted average of 491.1 {I2} (1974Ch11) and 491.3 {I2}
81SE2cG (1975Kr08).
81SE cG RI weighted average of 42.5 {I5} (1974Ch11) and 42.7 {I23}
81SE2cG (1975Kr08).
81SES G KC=0.00258 4$LC=0.000279 4$MC=4.33E-5 6$NC+=3.64E-6 6
81SES G NC=3.64E-6 6
81SE L 623.89 16 5/2-
81SE B 1.58 AP 6.57 AP
81SES B EAV=1383.3 13
81SE G 156.0 2 1.42 20 [M1,E2] 0.10 7
81SES G KC=0.08 6$LC=0.010 7$MC=0.0015 11$NC+=0.00012 9
81SES G NC=0.00012 9
81SE G 521.1 2 7.0 7
81SE cG E weighted average of 521.1 {I2} (1974Ch11) and 521.1 {I2}
81SE2cG (1975Kr08).
81SE cG RI weighted average of 7.3 {I7} (1974Ch11) and 6.0 {I13}
81SE2cG (1975Kr08).
81SE L 1052.83 20 5/2+
81SE B 0.36 AP 6.95 AP
81SES B EAV=1179.7 13
81SE G 949.7 2 1.75 30
81SE L 1303.48 205/2+
81SE B 0.20 AP 7.03 AP
81SES B EAV=1061.5 13
81SE G 836.1 2 1.64 20
81SE L 1406.13 133/2-
81SE B 1.44 AP 6.10 AP
81SES B EAV=1013.2 13
81SE G 915.0 2 0.51 10
81SE G 938.9 2 1.66 30
81SE G 1406.0 2 4.99 6
81SE L 2029.60 161/2-,3/2-
81SE B 0.60 AP 5.95 AP
81SES B EAV=724.1 13
81SE G 1561.9 2 1.88 20
81SE G 2029.6 2 1.12 10
81SE L 2179.18 19
81SE G 1688.4 2 0.56 6
81SE L 2332.49 135/2+
81SE B 0.25 AP 6.01 AP
81SES B EAV=586.8 13
81SE G 1842.1 2 0.35 5
81SE G 1864.5 2 0.57 6
81SE G 2332.3 2 0.33 5
81SE L 2569.86 13(1/2-,3/2-,5/2-)
81SE B 0.61AP 5.33 AP
81SES B EAV=481.5 12
81SE G 2079.3 2 0.34 5
81SE G 2102.2 2 1.83 20
81SE G 2569.5 2 0.86 10
81SE L 2659.65 20 (5/2)-
81SE B 0.154 AP 5.81 AP
81SES B EAV=442.3 12
81SE G 2659.6 2 0.77 9
81SE L 2769.61 19 (5/2-)
81SE B 0.33 AP 5.32 AP
81SES B EAV=394.9 12
81SE G 2145.8 2 0.28 5
81SE G 2301.8 2 1.37 14
81SE L 2935.12 18(5/2)-
81SE B 0.46 AP 4.90 AP
81SES B EAV=325.0 12
81SE G 756.0 2 0.86 10
81SE G 1882.0 2 0.04 LT
81SE G 2832.4 2 1.42 15
81SE L 2965.01 21(5/2-)
81SE B 0.21 AP 5.19 AP
81SES B EAV=312.6 12
81SE G 1661.8 2 0.66 10
81SE G 2340.8 2 0.39 6
81SE L 3222.6 15(5/2)- H ?
81SE B 0.13 LT 4.9 GT ?
81SES B EAV=209.2 12
81SE G 2733.3 2 0.48 7 F ?
81SE G 3118.2 2 0.18 5 F ?