181TA 181HF B- DECAY 1974HEYW,1990HE02,1988BU1305NDS 200601
181TA H TYP=FUL$AUT=S. -C. WU$CIT=NDS 106, 367 (2005)$CUT=31-Aug-2005$
181TA c 1990He02: {+181}Hf activity produced by {+180}Hf(n,|g);
181TA2c coaxial Ge detector; E|g, I|g measured.
181TA c 1988Bu13: {+181}Hf activity produced by {+180}Hf(n,|g);
181TA2c |b-spectrometer; Geiger-Muller counter; Ge detector;
181TA3c measured I(ce), E|g, I|g.
181TA c 1965Fu11: {+181}Hf activity produced by {+180}Hf(n,|g);
181TA2c Spectrometer, NaI(Tl) detector;
181TA3c measured E|b, E|g, I|b, I|g, |b|g-, |g|g-coin.
181TA c 1962El09: {+181}Hf activity produced by {+180}Hf(n,|g);
181TA2c long lens beta-ray spectrometer, Nai(Tl) scintillation counter;
181TA3c measured I|b, I(ce), |b|g-coin.
181TA c Other references: 1959Bo63, 1971Av02, 1969Bl12, 1976Ca11, 1979In02,
181TA2c 1969GuZW, 1977Fr10, 1961Mu03, 1965Fu11, 1966Al05, 1966As02,
181TAxc 1956Bo67.
181TA cG RI$From 1990He02, except where noted. The intensity of the 133|g
181TA2cG was increased from 44.5 {I10} to 53.8 {I6}, and the 136|g+137|g doublet
181TA3cG from 7.2 {I3} to 8.34, the values given in the previous evaluation.
181TA cG E$Weighted average of values from 1956Bo67, 1974HeYW, and 1988Bu13.
181TA cB IB$From 1965Fu11
181TA cL E$From least-square fit to E|g's
181TA cL J$From adopted levels
181TA N 0.805 4 1.00 1.0
181TA cN NR$normalized assuming the sum of the total intensity
181TA2cN to the ground state and the first excited state is 100.
181HF P 0.0 1/2- 42.39 D 6 1029.8 21
181TA L 0.0 7/2+ STABLE
181TA B 1045 30 0.0007LT 13.7GT ?
181TAS B EAV= 345.0 11
181TA cB E$from 1962El09, other value |?1050 from 1959Bo63.
181TA cB IB$a weak |b-decay branch to this level was seen by 1959Bo63
181TA2cB and 1962El09, but not by 1965Fu11 where the limit was established.
181TA3cB Direct feeding to this level is third-forbidden and should be
181TA4cB negligible. Note also that weak, apparent feeding to the 482 level
181TA5cB was observed by 1959Bo63 and 1962El09. Observation of these transitions
181TA6cB in some experiments may indicate
181TA6cB the existence of a 9/2+ {+181}Hf |b{+-} decaying isomer. Similar
181TA7cB isomers are observed in {+177}Hf and {+179}Hf.
181TA L 6.12 109/2-
181TA G 6.3 3 0.0143 5 E1 70.525
181TAS G MC= 24.3
181TA cG RI$calculated by the evaluator from the intensity balance. Other
181TA2cG values: 0.0125 {I28} from I(6.2|g)/L{-|a} x ray=0.0175 {I38} and
181TA3cG I(482|g)/L{-|a} x ray=13.99 {I4} from 1976Ca11
181TA cG M$from {+181}W |e decay
181TA cG CC anomalous E1 with penetration parameter |l=-9 {I1} from
181TA2cG 1969Bl12. The uncertainty in |a is from the penetration
181TA3cG parameter only. Note that this value for |a is consistent
181TA4cG with the intensity of the 476-keV |g feeding the 6-keV level.
181TA5cG ce(M1):ce(M2):ce(M45):ce(M3)=1.9(2):3.3(3):1.7(2):1
181TA6cG ce(N1):ce(N2):ce(N3):ce(N45)=1.6(4):2.3(4):7.0(35):1 (1969Bl12)
181TA L 136.252 189/2+
181TA G 136.260 18 7.27 23 M1+E2 +0.396 11 1.75 1
181TAS G KC= 1.37 $LC= 0.287 $MC= 0.0670 $NC+= 0.0199
181TA cG MR$from adopted gammas.
181TA2cG |d=+0.41 {I3} from |a and sign from (136|g)(346|g)(|q);
181TA3cG A{-2}=+0.224 {I27}, A{-4}=-0.014 {I7} averaged from 1971Av02, 1969Kl11,
181TA4cG 1972BeYN, and 1970WiZO.
181TA cG RI$from ce(K)(136)/ce(K)(133)=0.3713 {I10},
181TA2cG ce(L1)(136)/ce(L3)(133)=0.1084 {I7} (1988Bu13); and
181TA3cG |a(K)exp(133)=0.497, I|g(136|g+137|g)=8.34. I|g=7.23 {I31} from the
181TA4cG ce(K) ratios and I|g=7.33 {I35} from the ce(L) ratios. Others: from
181TA5cG I|g(136):I|g(137)=4.7 {I2}:0.67 {I12} (1971Av02) and
181TAxcG I|g(136+137)=8.34, I|g=7.3 {I13}.
181TA L 482.10 45/2+ 10.8 NS 1
181TA cL T$weighted average of 10.6 ns {I4} (1961Ma47), 11.0 ns {I2}
181TA2cL (1961Na06), 11.0 ns {I1} (1963Ma10), 10.4 ns {I2} (1965So02), 10.3 ns
181TA3cL {I3} (1966Ho13), 11.2 ns {I4} (1969Hr02), 10.56 ns {I15} (1965Me08),
181TA4cL and 11.0 ns {I3} (1971Bo13). These values were measured by |g|g(t).
181TA B 547 20 0.5 LT 9.9GT 1U?
181TAS B EAV= 165.6 9
181TA cB E$from 1962El09. Other value: |?550 from 1959Bo63.
181TA cB IB$see comments on ground-state feeding.
181TA G 345.93 6 18.78 12 E2 0.0544
181TAS G KC= 0.0387 $LC= 0.0120 $MC= 0.00288 $NC+= 0.000821
181TA cG M$Q from 133|g-(346|g)-136|g and 133|g-346|g angular correlations
181TA2cG (1971Av02); BM2W <1 from RUL rules out M2.
181TA G 475.99 9 0.873 7 M2+E3 0.5 1 0.168 8
181TAS G KC= 0.154 $LC= 0.0286 $MC= 0.00662 $NC+= 0.00196
181TA cG RI$from 1990He02. Other values: 0.758 {I22} (1977Fr10),
181TA2cG 0.5 {I1} (1971Av02), 0.92 {I5} (1976Ca11), and 1.45 {I20} (1974HeYW).
181TA3cG The large, statistically significant, intensity variations
181TA4cG reported for this transition may indicate the existence
181TA5cG of a previously unreported |b-decaying isomer in {+181}Hf. See also
181TA6cG the comments on possible |b feeding to the ground state.
181TA G 482.18 9 100.00 14 M1+E2 4.76 4 0.0295 8
181TAS G KC= 0.0183 $LC= 0.00416 $MC= 0.000976 $NC+= 0.000283
181TA cG MR$from L1/L2=2.85 {I3}, L2/L3=2.17 {I3} (1983Bu18).
181TA2cG Others: 6.2 {I7} from (133|g)(482|g)(|q),
181TA2cG A{-2}=-0.289 {I11}, A{-4}=-0.074 {I4}, averaged from 1971Av02,
181TA3cG 1971Sc05, 1977Fr10, and 1969Va22.
181TA cG CC$anomalous transition with penetration parameter |l=150 {I1}
181TA2cG (1988Bu13). |l=176 {I15} (from 1971Av02, recalculated by the
181TA3cG evaluator). |a(K)exp weighted average of 0.026 {I2}, 0.024 {I1}, 0.023
181TA4cG {I2}, and 0.021 {I2} compiled by 1966Ha50 and 0.0234 {I15} (1971Av02).
181TA cG M$a small parity-violating E1 admixture to this transition has been
181TA2cG investigated by many authors. A precise value for
181TA3cG p(|g)=-6.1|*10{+-6} {I7} was measured by 1971Lo09. For additional
181TA4cG values see 1967Lo04, 1967Va29, 1969Cr02, 1970Bo50,
181TA5cG 1970Va20, 1971Bo03, 1971De01, 1972Li11,
181TA6cG 1972Ku23, and 1974Sc21.
181TA L 615.12 41/2+ 17.6 US 2
181TA cL T$weighted average of 20.1 |ms {I7} (1948Bu14), 17.2 |ms {I2}
181TA2cL (1953Ba60), 18.8 |ms {I5} (1953Mu60) measured by |bce(t); and 17.83
181TA3cL |ms {I10} (1959Li44), 17.5 |ms {I8} (1960Be19), 17.23 |ms {I14}
181TA4cL (1969FaZY), 18.1 |ms {I3} (1970Gl02) measured by |b|g(t).
181TA B 405 5 93 3 7.18 2
181TAS B EAV= 120.7 9
181TA cB E$from 1953Ba81. Other values: 408 {I8} (1952Fa14), 408 (1965Fu11).
181TA G 133.021 19 53.8 6 E2 1.27
181TAS G KC= 0.497 $LC= 0.582 $MC= 0.145 $NC+= 0.0420
181TA cG M$L1/L2=0.184 {I2}, L2/L3=1.20 {I1} (1983Bu18), L1/L23=0.1004 {I12}
181TA2cG (1989Ki23). Penetration parameters |l(1)=22 {I4}, |l(2)=-11 {I4}
181TAxcG (1989Ki23).
181TA G 615.17 11 0.290 22 M3(+E4) 0.194
181TA cG MR$|d=0.7 {I3} from |a(K)exp=0.132 20
181TA2cG and K:L:M+=11.9 5:2.4 1:0.32 6 (1971Av02).
181TA3cG See comment in adopted gammas.
181TAS G KC= 0.129 19$LC= 0.033 4
181TA L 618.92 5 3/2+ 0.87 NS 2
181TA cL T from |b|g(t) (1965Sh16)
181TA B 404 7 3 8.3025
181TAS B EAV= 119.4 9
181TA cB E$from 1965Fu11
181TA G 3.90 10 [M1] 2684 5.6 27 ?
181TAS G MC= 2018
181TA cG TI$calculated from the measured |b intensity and intensity balance.
181TA G 136.86 4 1.07 23 M1 1.83
181TAS G KC= 1.52 $LC= 0.239 $MC= 0.0541 $NC+= 0.0163
181TA cG E$from bent crystal spectrometer measurement (1956Bo67).
181TA cG RI$from I|g(136+137)=8.34 and I|g(136)=7.27 {I23} (see comment on
181TAxcG 136|g).
181TA cG M,MR$L1:L2:L3=1.0:0.095:<0.01 and %E2=1 {I4} from 1966Al05;
181TA2cG |a(K)exp=2.2 {I6} from 1971Av02.
181TA G 618.66 8 0.0311 15 (E2) 0.0122
181TAS G KC= 0.00958 $LC= 0.00194
181TA cG M$ |a(K)exp=0.009 {I4} from 1988Bu13.