157EU 157SM B- DECAY 1994WIZZ,1997GR09,1996GR2016NDS 201602
157EU H TYP=FUL$AUT=N. NICA$CIT=NDS 132, 1 (2016)$CUT=4-Dec-2015$
157EU c For these decay scheme studies, {+157}Sm has been produced by the
157EU2c {+160}Gd(n,|a) reaction, n fission of {+235}U with isotope
157EU3c separation, and spontaneous fission of {+252}Cf with chemical
157EU4c separation. Measurements have included |g singles and
157EU5c |g|g-coincidence spectra with Ge detectors, |b- spectra with
157EU6c plastic and anthracene detectors, and |g|b- coincidences.
157EU c Experimental methods:
157EU c 1960Wi10: Produced by {+160}Gd(n,|a), but T{-1/2} reported as 0.5
157EU2c min {I1}, so isotope probably misassigned.
157EU c 1972Mo28: Produced by {+160}Gd(n,|a) with E{-n}=14.7 MeV on
157EU2c enriched (96.5%) target. Report |g of 121 keV and E{-|b-}
157EU3c of 2.83 MeV {I10}, but report T{-1/2}=83 s
157EU4c {I1}, so isotope probably misassigned.
157EU c 1973Da05: Produced by {+160}Gd(n,|a) reaction with E{-n}=14.8 MeV
157EU2c on natural target. |g measured with Ge detector, |b- with
157EU3c anthracene detector, and |g|b- coincidences. Report 7 |g's,
157EU4c but report isotope assignment is not certain.
157EU c 1973Ka23: Produced by {+160}Gd(n,|a) reaction with fast n on
157EU2c enriched (95.2%) target. |g measured with Ge detectors, |g|g
157EU3c coincidences with Ge detectors, and |b- with plastic detectors.
157EU4c Report 14 |g's.
157EU c 1980Ba51: Produced from {+252}Cf spontaneous fission with chemical
157EU2c separation. |g measured with Ge detector. Report 23 |g's, but
157EU3c no decay scheme.
157EU c 1986Ma12: Produced by n fission of {+235}U with isotope separation.
157EU2c |g singles and |g|g coincidences measured with Ge detectors.
157EU3c T{-1/2} measured.
157EU c 1994WiZZ: Produced from {+252}Cf spontaneous fission with chemical
157EU2c separation. |g measured with Ge detector. Same authors as
157EU3c 1980Ba51.
157EU c 1993Gr17: Produced from {+252}Cf spontaneous fission with isotope
157EU2c separation. Measured |b- end-point energy with Ge detector.
157EU c 1996Gr20: Produced from {+252}Cf spontaneous fission with isotope
157EU2c separation. Measured |b- intensity for "ground-state" branch
157EU3c with total absorption |g-ray spectrometer.
157EU c 1997Gr09: Produced from {+252}Cf spontaneous fission with isotope
157EU2c separation. Measured |b- branch intensity as a function of the
157EU3c excited level energy with total absorption |g-ray spectrometer.
157EU cB IB Relative values are from |g-ray intensity balances for
157EU2cB levels with deexciting |g's, except for the 76 level. These
157EU3cB values are converted to absolute values by including the values
157EU4cB from the total absorption |g spectra, TAGS, for the ground
157EU5cB state (1996Gr20) and the pseudolevels (1997Gr09). The values
157EU6cB from the intensity balances and TAGS data are in good agreement.
157EU7cB The |b- intensity distribution from the total
157EU8cB absorption |g spectra (TAGS) (1997Gr09) indicate that
157EU9cB |? 9.4% of the decays are to levels that are not in the |g-ray
157EUAcB decay scheme, namely, |? 850, 1050 - 1250, and above 1500 keV.
157EUBcB These decays are represented here by pseudolevels which do not
157EUCcB have any depopulating |g's. These pseudolevels represent the
157EUDcB sum of the |b- feeding to all the actual levels in an energy
157EUEcB range. Where the pseudolevels are adjacent, this range is half
157EUFcB of the distance between the adjacent levels; and where a
157EUGcB pseudolevel is between discrete levels, the range is between
157EUHcB these levels.
157EUIcB No uncertainties are included for the I{-|b-} to the
157EUJcB pseudolevels, and no log {Ift}'s are given since this intensity
157EUKcB is expected to be distributed over several actual levels.
157EU cB IB,LOGFT$The inability to include the unknown |g decays from the
157EU2cB upper levels will, in principle, cause the I{-|b-} values
157EU3cB deduced from the |g intensity balances to be incorrect; however,
157EU4cB since most of these unknown |g's are expected to populate the
157EU5cB strongly fed levels
157EU6cB below 460 keV, the changes in the log {Ift} values are probably
157EU7cB small. The uncertainties in the I{-|b-} and log {Ift}'s do not
157EU8cB include any contributions from the incompleteness of the decay
157EU9cB scheme.
157EU cG The |g|g coincidences noted in the decay-scheme drawing
157EU2cG are those of 1973Ka23.
157EU cG The unplaced |g's are those of 1994WiZZ.
157EU cG E,RI From 1994WiZZ. Others: 1973Da05 and 1973Ka23.
157EU cG M All assignments are deduced from the assigned J|p values.
157EU2cG The intensity balance at 77 level supports the multipolarity
157EU3cG of the 77 |g.
157EU DG CC$FROM BrIcc v2.3a (30-Jun-2013) 2008Ki07, "Frozen Orbitals" appr.
157EU DG MR$IF NO VALUE GIVEN IT WAS ASSUMED MR=1.00 FOR E2/M1,
157EU2DG MR=1.00 FOR E3/M2 AND MR=0.10 FOR THE OTHER MULTIPOLARITIES
157EU cL E From least-squares fit to |g energies.
157EU cL J From {+157}Eu Adopted Levels and in agreement with J|p and
157EU2cL band assignments of 1994WiZZ and those in the {+158}Gd(pol t,|a)
157EU3cL study (1979Bu05). See 1990Ja11 for review of band assignments.
157EU cL E(a)$Pseudo levels, which are artificially introduced, the
157EU2cL placement and number of which is quite arbitrary and merely indicates
157EU2cL that in those energy regions a certain amount of |b-feeding is
157EU2cL required to fit the measured spectrum.
157EU cL BAND(A) 5/2[413] band
157EU cL BAND(B) 5/2[532] band
157EU cL BAND(C) 3/2[411] band
157EU cL BAND(D) 1/2[411] band
157SM P 0.0 (3/2-) 8.03 M 7 2781 6
157EU N 0.56 10 1.0 1.0
157EU cN NR computed to give 100% |b- decay; the uncertainty does not
157EU2cN include any contribution due to the incompleteness of the
157EU3cN |g-ray portion of the decay scheme.
157EU PN 3
157EU G 31.07 7 0.29 7
157EU G 31.78 5 0.39 7
157EU G 37.30 8 0.85 6
157EU G 60.58 9 0.15 6
157EU G 61.40 11 1.2 LT
157EU G 62.62 5 0.24 5
157EU G 74.88 15 0.08 4
157EU G 77.94 5 0.17 3
157EU G 81.11 5 0.19 3
157EU G 88.38 6 0.15 3
157EU G 186.00 16 0.44 17
157EU G 193.4 3 1.9 5
157EU G 315.2 4 0.42 6
157EU G 557.54 10 0.75 7
157EU G 641.46 16 0.40 6
157EU G 724.19 19 0.45 8
157EU G 797.36 24 0.48 13
157EU G 844.0 3 0.45 12
157EU G 846.0 3 0.58 12
157EU G 868.52 14 0.58 13
157EU G 909.3 3 0.51 13
157EU G 911.7 3 0.61 3
157EU G 1028.16 11 1.02 9
157EU G 1354.67 23 0.63 11
157EU G 1407.65 18 0.61 8
157EU L 0.0 5/2+ A
157EU B 3 LE 7.1 GE
157EUS B EAV=1116.0 28
157EU cB IB From 4|p|g|b coincidence data (1996Gr20), I{-|b-}(0+77)=
157EU2cB 0.3 {I+29-3}.
157EU L 76.709 6 7/2+ A
157EU B 2.5 25 8.5 GE 1U
157EUS B EAV=1065.1 27
157EU cB IB From log {If{-1u}t} |> 8.5 from systematics (1998Si17) as
157EU2cB well as from I{-|b-}(0+77)=0.3 {I+29-3} (1996Gr20).
157EU G 76.701 7 3.35 12[M1+E2] 5.2 13 C
157EUS G KC=2.8 6$LC=1.9 14$MC=0.4 4
157EUS G NC=0.10 8$OC=0.013 10$PC=0.00027 11
157EU L 197.863 6 5/2- B
157EU B 43 8 6.3 2 C
157EUS B EAV=1026.3 28
157EU cB E From |g|b- coincidences E{-|b-}(197)=2400 {I200} which
157EU2cB implies Q{-|b{+-}}=2600 {I200} (1973Da05,1973Ka23) compared
157EU3cB singles measurement of Q{-|b{+-}}=2734 {I50} (1993Gr17).
157EU G 121.147 7 8.50 16[E1] 0.1689 C
157EUS G KC=0.1425 20$LC=0.0208 3$MC=0.00447 7
157EUS G NC=0.001007 15$OC=0.0001526 22$PC=1.221E-5 17
157EU G 197.870 8 100.0 3 [E1] 0.0451 C
157EUS G KC=0.0383 6$LC=0.00537 8$MC=0.001153 17
157EUS G NC=0.000261 4$OC=4.03E-5 6$PC=3.49E-6 5
157EU L 263.228 14 7/2- B
157EU G 65.44 10 0.13 4 [M1,E2] 9 3
157EUS G KC=4.2 12$LC=4 4$MC=0.9 8
157EUS G NC=0.20 17$OC=0.027 22$PC=0.00041 18
157EU G 186.55 3 1.45 7[E1] 0.0527 C
157EUS G KC=0.0447 7$LC=0.00630 9$MC=0.001353 19
157EUS G NC=0.000307 5$OC=4.71E-5 7$PC=4.05E-6 6
157EU G 263.207 22 2.40 12 [E1] 0.0214 C
157EUS G KC=0.0182 3$LC=0.00251 4$MC=0.000539 8
157EUS G NC=0.0001224 18$OC=1.90E-5 3$PC=1.705E-6 24
157EU L 394.334 9 3/2+ C
157EU B 13 7 6.7 3
157EUS B EAV=937.7 27
157EU G 196.461 9 29.7 4 [E1] 0.0459 C
157EUS G KC=0.0390 6$LC=0.00547 8$MC=0.001176 17
157EUS G NC=0.000266 4$OC=4.10E-5 6$PC=3.55E-6 5
157EU G 317.46 7 2.32 14[E2] 0.0489 C
157EUS G KC=0.0381 6$LC=0.00846 12$MC=0.00190 3
157EUS G NC=0.000427 6$OC=6.29E-5 9$PC=3.58E-6 5
157EU G 394.351 16 21.3 3 [M1,E2] 0.034 9 C
157EUS G KC=0.029 8$LC=0.0045 6$MC=0.00099 10
157EUS G NC=0.000226 24$OC=3.5E-5 5$PC=3.0E-6 10
157EU L 453.500 12 5/2+ C
157EU B 17 7 6.5 3
157EUS B EAV=911.1 27
157EU G 59.168 10 2.00 5 [M1,E2] 13 5 C
157EUS G KC=5.3 19$LC=6 6$MC=1.4 13
157EUS G NC=0.3 3$OC=0.04 4$PC=0.0005 3
157EU G 190.273 17 2.01 7 [E1] 0.0500 C
157EUS G KC=0.0424 6$LC=0.00597 9$MC=0.001282 18
157EUS G NC=0.000291 4$OC=4.47E-5 7$PC=3.85E-6 6
157EU G 376.70 11 0.52 6 [M1,E2] 0.039 10
157EUS G KC=0.032 9$LC=0.0052 5$MC=0.00114 10
157EUS G NC=0.000259 23$OC=4.0E-5 5$PC=3.4E-6 12
157EU G 453.47 6 0.72 20 [M1,E2] 0.024 7
157EUS G KC=0.020 6$LC=0.0030 5$MC=0.00066 10
157EUS G NC=0.000151 23$OC=2.4E-5 4$PC=2.1E-6 7
157EU L 670.419 25
157EU B 2.6 5 7.2 2
157EUS B EAV=814.2 27
157EU G 216.95 6 0.57 7 C
157EU G 276.05 3 1.76 6 C
157EU G 472.65 6 1.37 8
157EU G 670.46 11 0.90 7
157EU L 716.31 5
157EU B 1.7 4 7.3 2
157EUS B EAV=793.8 27
157EU G 321.78 10 0.46 5
157EU G 453.1 4 0.54 14
157EU G 518.46 11 0.57 6 &
157EU G 716.40 7 1.39 8
157EU L 850. a
157EU B 0.2
157EUS B EAV=734.6 27
157EU L 971.99 9 3/2+ D
157EU B 0.7 2 7.4 3
157EUS B EAV=681.0 27
157EU G 518.46 11 0.57 6 [M1,E2] 0.017 5 &
157EUS G KC=0.014 4$LC=0.0021 4$MC=0.00046 8
157EUS G NC=0.000104 19$OC=1.6E-5 4$PC=1.5E-6 5
157EU G 577.69 12 0.62 9 [M1,E2] 0.013 4
157EUS G KC=0.011 4$LC=0.0016 4$MC=0.00034 7
157EUS G NC=7.8E-5 16$OC=1.2E-5 3$PC=1.1E-6 4
157EU L 988.38 10
157EU B 1.9 5 7.0 3
157EUS B EAV=673.9 27
157EU G 534.60 20 0.34 7
157EU G 594.24 17 0.51 8
157EU G 988.38 13 2.6 4
157EU L 1021.27 10
157EU B 0.8 2 7.3 2
157EUS B EAV=659.5 27
157EU G 758.2 3 0.37 9
157EU G 823.39 10 1.00 8
157EU L 1050 a
157EU B 1.6
157EUS B EAV=647.0 27
157EU L 1150 a
157EU B 0.7
157EUS B EAV=603.6 26
157EU L 1250 a
157EU B 1.0
157EUS B EAV=560.5 26
157EU L 1360.92 13
157EU B 1.2 2 6.8 3
157EUS B EAV=513.3 26
157EU G 966.2 3 0.54 10
157EU G 1163.14 14 1.52 12
157EU L 1377.32 12
157EU B 1.0 2 6.8 3
157EUS B EAV=506.3 26
157EU G 1300.1 3 0.57 13
157EU G 1377.40 12 1.25 10
157EU L 1382.94 8
157EU B 1.2 4 6.7 3
157EUS B EAV=504.0 26
157EU G 988.2 1 0.9 4
157EU2 G FL=394.334
157EU G 1185.65 12 1.24 11
157EU2 G FL=197.863
157EU L 1418.47 18
157EU B 0.7 2 6.9 3
157EUS B EAV=489.0 26
157EU G 1155.04 24 0.64 12
157EU G 1220.82 25 0.57 11
157EU L 1463.12 7
157EU B 3.8 7 6.2 3
157EUS B EAV=470.2 26
157EU G 1386.35 10 1.76 11
157EU G 1463.16 9 5.1 3
157EU L 1550 a
157EU B 0.4
157EUS B EAV=433.9 25
157EU L 1650 a
157EU B 0.6
157EUS B EAV=392.8 25
157EU L 1750 a
157EU B 0.7
157EUS B EAV=352.2 25
157EU L 1850 a
157EU B 1.2
157EUS B EAV=312.3 24
157EU L 1950 a
157EU B 1.2
157EUS B EAV=273.3 24
157EU L 2050 a
157EU B 0.5
157EUS B EAV=235.2 23
157EU L 2150 a
157EU B 0.3
157EUS B EAV=198.1 22
157EU L 2250 a
157EU B 0.4
157EUS B EAV=162.3 22
157EU L 2350 a
157EU B 0.3
157EUS B EAV=127.8 21
157EU L 2450 a
157EU B 0.2
157EUS B EAV=94.9 20
157EU L 2550 a
157EU B 0.2
157EUS B EAV=63.9 19