254MD 258LR A DECAY (3.92 S) 1971ES01 19NDS 201902
254MD H TYP=FUL$AUT=BALRAJ SINGH$CIT=NDS 156, 1 (2019)$CUT=31-Jan-2019$
254MD c 1971Es01: {+258}Lr source was produced in {+15}N bombardments of
254MD2c {+249}Cf and {+248}Cm targets, and {+12}C, {+13}C bombardments of
254MD3c {+249}Cf target; the authors used {+11}B and {+10}B beams on {+249}Cf
254MD4c target.
254MD c 1976BeZY: {+258}Lr produced in {+249}Cf({+15}N,|a2n). Measured E|a,
254MD2c I|a, half-life at ORNL accelerator facility.
254MD c 2014Ha04: {+258}Lr produced as daughter from |a decay of
254MD2c {+262}Db, which was produced via the reaction {+248}Cm({+19}F,5n)
254MD3c at beam energies of 97.4 and 103.1 MeV from the RIKEN Linear
254MD4c Accelerator (RILAC). The evaporation residues (EVR) were separated in
254MD5c flight from beam particles and majority of nuclear transfer products
254MD6c by the gas-filled recoil ion separator (GARIS) and transported
254MD7c to the rotating wheel apparatus MANON (measurement system for Alpha-
254MD8c particle and spontaneous fission events On-line). They were deposited
254MD9c on mylar foils and set on the wheel between 15 pairs of Si PIN
254MDAc photodiodes with separated signals for |a-particles
254MDBc (1-20 MeV) and spontaneous fission (SF) fragments (5-150 MeV). FWHM
254MDCc for |a detection was 50 keV in the top detectors and about 100 keV in
254MDDc the bottom ones. Measured time-correlated |a|a and |a(SF) events
254MDEc in the |a energy range of 8.0 MeV |< E{-|a} |<9.0 MeV and SF fragment
254MDFc energy range E{-SF} |>30 MeV.
254MD c The deduced |a hindrance factors for both sets of E|a and
254MD2c I|a data, measured by two different groups, as well as the level
254MD3c spacings indicate some abnormalities, perhaps, the possible existence
254MD4c of some impurities in their sources.
254MD cA E$|a energies measured by 1971Es01 and 1976BeZY differ by
254MD2cA 30-50 keV. The published data of 1971Es01 are listed here, and
254MD3cA those of 1976BeZY are quoted for comparison.
254MD cA E$The original energies have not been adjusted for changes in
254MD2cA calibration energies, as the changes would be well within the
254MD3cA uncertainties for E|a values:
254MD4cA E|a({+213}Fr)=6773, E|a({+211}Po)=7443 and E|a({+253}Es)=6640 were
254MD5cA used by 1971Es01, and E|a({+244}Cm)=5804.9, E|a({+243}Am)=5274.8 and
254MD6cA E|a({+249}Cf)=5813.5 were used by 1976BeZY for energy calibration.
254MD7cA 1991Ry01 recommends E|a({+244}Cm)=5804.77 {I5}, E|a({+243}Am)=5275.3
254MD8cA {I10}, E|a({+249}Cf)=5812.8 {I16}; E|a({+213}Fr)=6775 {I2},
254MD9cA E|a({+211}Po)=7449.3 {I13}, E|a({+253}Es)=6632.51 {I5} have been
254MDAcA adopted in the ENSDF database. In 2014Ha04, a broad |a group
254MDBcA is reported at 8.61 MeV, which probably corresponds to the known
254MDCcA |a lines as listed in the table here.
254MD cA IA$|a intensity per 100 |a decays. I|a values of 1971Es01 and
254MD2cA 1976BeZY are not in perfect agreement. I|a measured by 1971Es01
254MD3cA are listed; I|a measured by 1976BeZY are also quoted.
254MD cA HF$r{-0}({+254}Md)=1.48 {I1}, deduced from r{-0} systematics
254MD2cA given in 1998Ak04, is used in calculations. The calculated HFs and the
254MD3cA level spacings are quite different from that for the normal behavior
254MD4cA in this region. They may indicate perhaps some impurity in the source,
254MD5cA or that the deduced partial |a-decay half-lives are not correct.
258LR P 0.0 3.92 S 33 8904 19
258LR cP T$From {+258}Lr Adopted Levels in the ENSDF database (August 2017
258LR2cP update)
258LR cP QP$From 2017Wa10
254MD N 0.974 18
254MD cN BR$%|a=97.4 {I18} (from {+258}Lr Adopted Levels)
254MD L 83 30
254MD cL $If E|a=8648 {I10} (1976BeZY), then E(level)=120 {I23}.
254MD A 8680 20 7 2 4.7 AP
254MD cA $E|a=8648 {I10} and I|a=10 {I2} were measured by 1976BeZY.
254MD2cA When these measurements are used, HF|?2.6.
254MD L 114 30
254MD cL $If E|a=8614 {I10} (1976BeZY), then E(level)=154 {I23}.
254MD A 8650 20 16 3 1.7 AP
254MD cA $E|a=8614 {I10} and I|a=35 {I5} were measured by 1976BeZY.
254MD2cA When these measurements are used, HF|?0.6.
254MD L 144 30
254MD cL $If E|a=8589 {I10} (1976BeZY), then E(level)=180 {I23}.
254MD A 8620 20 47 3 0.5 AP
254MD cA $E|a=8589 {I10} and I|a=45 {I7} were measured by 1976BeZY.
254MD2cA When these measurements are used, HF|?0.4.
254MD L 175 30
254MD cL $If E|a=8540 {I20} (1976BeZY), then E(level)=230 {I30}.
254MD A 8590 20 30 4 0.6 AP
254MD cA $E|a=8540 {I20} and I|a=10 {I5} were measured by 1976BeZY.
254MD2cA When these measurements are used, HF|?1.2.