Author: Balraj Singh |  Citation: ENSDF |  Cutoff date: 14-Jan-2022 

Author: Balraj Singh |  Citation: ENSDF |  Cutoff date: 20-JUL-2015 

 Full ENSDF file | Adopted Levels (PDF version) 

Q(β-)=13710 keV SYS(n)= 3220 keV SYS(p)= 14890 keV SYQ(α)= -10760 keV SY
Reference: 2021WA16

General Comments:

1995CzZZ (short conference paper): possible identification of 118Tc in 9Be(238U,f) at 750 MeV/nucleon at GSI facility. But in subsequent published works (1997Be70,1998Do08) by the same group, there was no mention of the formation or identification of the 118Tc isotope; the heaviest Tc isotope identified was 117Tc in 1997Be70 and 115Tc in 1998Do08 (where a Pb target was used instead of Be). In 1995CzZZ, there was no detailed discussion about the formation of new isotopes, 118Tc was simply shown in the chart of nuclides figure 2 in their paper. In the absence of sufficient confirmatory evidence from the same experimental group (1994Be24,1995CzZZ,1997Be70,1998Do08), the identification of 118Tc remained uncertain until the work by 2010Oh02

2010Oh02: 118Tc nuclide identified in Be(238U,F) and Pb(238U,F) reactions with a 238U86+ beam energy of 345 MeV/nucleon produced by the cascade operation of the RBIF accelerator complex of the linear accelerator RILAC and four cyclotrons RRC, fRC, IRC and SRC. Identification of 118Tc nuclei was made on the basis of magnetic rigidity, time-of-flight and energy loss of the fragments using BigRIPS fragment separator. Experiments performed at RIKEN facility. Based on α/Q spectrum and Z versus α/Q figure 2 in 2010Oh02, about 400 counts were assigned to 118Tc isotope. (Q and Q(β-)1 charge states)

2013So17: 118Tc isotope produced in 9Be(238U,X) reaction at 345 MeV/nucleon at RIBF-RIKEN facility. Fragments identified by Zero-degree spectrometer which analyzed events based on Bρ-tof-ΔE. Measured Eγ, Iγ, Eβ, (fragment)γ-coin, βγ-coin, γγ-coin

2015Lo04: 118Tc nuclide produced at RIBF-RIKEN facility in 9Be(238U,F) reaction at E=345 MeV/nucleon with an average intensity of 6×1010 ions/s. Identification of 118Tc was made by determining atomic Z and mass-to-charge ratio α/Q, where Q=charge state of the ions. The selectivity of ions was based on magnetic rigidity, time-of-flight and energy loss. The separated nuclei were implanted at a rate of 50 ions/s in a stack of eight double-sided silicon-strip detector (WAS3ABi), surrounded by EURICA array of 84 HPGe detectors. Correlations were recorded between the implanted ions and β rays. The half-life of 118Tc isotope was measured from the correlated ion-β decay curves and maximum likelihood analysis technique. Comparison of measured half-lives with FRDM+QRPA, KTUY+GT2 and DF3+CQRPA theoretical calculations

Production cross sections and yields of 118Tc:

2021Su01: measured production cross section in 9Be(238U,F), E=345 MeV/nucleon at RIBF-RIKEN facility.

2020Su23: measured production cross section in 9Be(132Sn,X), E=278 MeV/nucleon at RIBF-RIKEN facility.

2019Pe09: measured production σ in 208Pb(238U,F), E=950 MeV/nucleon at GSI facility.

Theoretical calculations: two primary reference for half-lives and decay mode from the NSR database available at are listed in the ’document’ records in this dataset.

Q-value: Estimated uncertainties (2021Wa16): 450 for Q(β-), 570 for S(n), 640 for S(p) and Q(α)

Q-value: S(2n)=8220 500, S(2p)=32640 500, Q(β-n)=8130 590 (syst, 2021Wa16).

Q-value: Q(β-2n)=4637 400, deduced by evaluator from mass excesses in 2021Wa16

  0 30 ms 4 
% β- = 100
% β-n = ?
% β-2n = ?

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Additional Level Data and Comments:

  0 30 ms 4 
% β- = 100
% β-n = ?
% β-2n = ?
Only β- decay mode is expected, followed by delayed-neutron decays, thus 100% β- decay is assigned by inference.
E(level): Only β- decay mode is expected, followed by delayed-neutron decays, thus 100% β- decay is assigned by inference.

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