157LU 161TA A DECAY 1986RU05,1992HA10,2012TH1316NDS 201602
157LU H TYP=FUL$AUT=N. NICA$CIT=NDS 132, 1 (2016)$CUT=4-Dec-2015$
157LU c Experimental methods:
157LU c 1979Ho10: produced by {+107}Ag({+58}Ni,2p2n) on enriched (99.5%)
157LU2c target with E({+58}Ni)=263, 275 MeV. Reaction products
157LU3c separated in velocity selector and implanted in
157LU4c position-sensitive detector.
157LU c 1983Al09, 1984Al36: From |b end-point energy and E(|a) value, they
157LU2c deduce proton binding energy.
157LU c 1986Ru05: produced by {+130}Ba({+35}Cl,4n) with E({+35}Cl)=200 MeV
157LU2c and {+133}Cs({+36}Ar,8n) with E({+36}Ar)=235 MeV. After He-jet
157LU3c transport, |a's measured with Si detector.
157LU c 1992Ha10: produced by {+40}Ca({+127}I,x) with E({+127}I)=711 MeV.
157LU c 2005Sc22: used {+112}Sn({+58}Ni,p), E({+58}Ni)=266 MeV reaction to
157LU2c produce {+169,169m}Ir and studied |a-decay products {+165,165m}Re,
157LU2c {+161}Ta, {+157}Lu. Recoils separated with He-filled magnetic
157LU2c separator (RITU) were transported to focal plane where they traversed
157LU2c isobutane-filled multiwire proportional chamber before implating into
157LU2c double-sided Si strip detectors (GREAT spectrometer); used array of
157LU2c 43 escape-suppressed Ge detectors for prompt |g-ray detection
157LU2c (JUROGAM). Measured E|g, I|g, |g|g-coin, (recoil)|g-coin.
157LU c 2012Th13: used {+92}Mo({+84}Sr,X) E({+84}Sr)=392, 400 MeV
157LU2c to produce g.s. and metastable {+173}Au and their separate g.s.-to-g.s.
157LU2c and metastable-to-metastable |a-decay chains to g.s. and metastable
157LU2c {+161}Ta respectively. Same setup as that from 2005Sc22 was used, with
157LU2c extra 28 Si PIN diode detectors and four clover-type Ge detectors and
157LU2c one planar Ge detector, allowing recording energy loss and
157LU2c time-of-flight information. Measured E|g, I|g, |a|g-, |g|g-coin;
157LU2c deduced prompt |g and mass excesses and compared with 2012Wa38
157LU2c evaluation.
157LU c A particularly of {+177}Tl, {+173}Au, {+169}Ir, {+165}Re, {+161}Ta,
157LU2c and {+157}Lu nuclei is that all ground states have J|p=1/2+ (based on
157LU2c |ps{-1/2} orbital) and all metastable states have J|p=11/2- (based on
157LU2c |ph{-11/2} orbital); consequently all ground states form an |a-decay
157LU2c chain connecting the 1/2+ spins, which is different from the |a-decay
157LU2c chain of all metastable states connecting 11/2- spins.
157LU cL E(A),J(A),T(A)$From Adopted Levels, Gammas dataset
161TA P 95 38 (11/2-) 3.08 S 11 5209 39
161TA cP E$from 2012Th13 based on measured metastable state energy in {+173}Au,
161TA2cP |DE({+173}Au)=214 {I23} (1999Po09), from which they deduced the
161TA2cP metastable state energy in {+165}Re, |DE({+165}Re)=58 {I37}; of which
161TA2cP they deduced the metastable state energy in {+161}Ta, |DE({+165}Re)=95
161TA2cP {I38} (literature Q(|a) values for the g.s.-to-g.s. and
161TA2cP metastable-to-metastable |a-decays listed on Fig. 1 of 2012Th13 were
161TA2cP also used in these calculations)
161TA cP J,T$from 2011Re14 evaluation
161TA cP QP$2012Th13 measured E|a=5142 {I5} from {+161}Ta that yielded
161TA2cP T{-1/2}=4.5 s {I11} consistent with the 11/2- metastable state in
161TA2cP {+161}Ta (T{-1/2} of {+161}Ta g.s. is not known) decaying to the
161TA2cP metastable state of {+157}Lu. Weighted average of experimental values
161TA2cP listed in the |a radiations table below is 5147 {I2}, whence one
161TA2cP gets Q(|a,{+161m}Ta->{+157m}Lu)=5278 {I2}. Consequently one gets the
161TA2cP Q(|b{+-})value of g.s.-to-g.s. |a decay (|DE denotes the metastable
161TA2cP state energy):
161TA2cP Q(|a,{+161}Ta->{+157}Lu)=|DE({+157}Lu)+Q(|a,{+161m}Ta->{+157m}Lu)-
161TA2cP |DE({+161}Ta)=26 {I7} + 5278 {I2} - 95 {I38}=5209 {I39}.
161TA2cP Other value: 5330 {I29} (2012Wa38)
157LU N 0.07 3
157LU cN BR$measured by 2012Th13 for {+161m}Ta->{+157m}Lu |a decay.
157LU2cN A theoretical value that was reported before (1984Al36) from
157LU2cN theoretical |a and |e+|b+ half-lives is 5%. 1983Al09 and
157LU3cN 1984Al36 suggest that {+161}Ta may also emit protons which
157LU4cN would decrease this value.
157LU L 0.0 (1/2+,3/2+) 6.8 S 18 A
157LU cL $no |a-decay to {+157}Lu g.s. was found
157LU L 26 7 (11/2-) 4.79 S 12 A
157LU cL $associated by 2012Th13 as daughter level of the |a-decay branch
157LU A 5147 2 100
157LU cA E$weighted average of experimental values
157LU2cA 5142 {I5} (2012Th13), 5151 {I4} (2005Sc22), 5140 {I7} (1996Pa01),
157LU2cA 5149 {I5} (1992Ha10), 5148 {I5} (1979Ho10)
157LU cA HF$1.6 {I8} (2012Th13)