Author: Balraj Singh |  Citation: Nucl. Data Sheets 156, 148 (2019) |  Cutoff date: 31-Jan-2019 

 Full ENSDF file | Adopted Levels (PDF version) 

S(n)= 7160 keV CAS(p)= 460 keV SYQ(α)= 11197 keV 13
Reference: 2017WA10,1997Mo25

General Comments:

1995Ho04: 209Bi(64Ni,n), E=316.1 MeV (no event observed), 318.1 MeV (one event observed) and 320.0 MeV (two events observed) at GSI using SHIP separator. Three position and time correlated chains of α particles were observed, with the α energies and time intervals between successive emissions. These decay chains were assigned to the decay of 272Rg through consistency of α-descendents of the chain whose α-energies and half-lives agreed with the known isotopes of 260Db and 256Lr. 1998Ho13 summarized results from previous experiments and reported production σ<2.9 pb at E=316.1 MeV (no events), 1.7 pb +33-14 at 318 MeV (one event), and 3.5 pb +46-23 at E=320 MeV (two events). See also related articles: 1997Ho13, 1997Ho03 and 1999He07.

History of three events in 1995Ho04:

Event #1 (1995Ho04):

Eα1=533 keV, Δt1=3.60 ms, assigned to 272Rg; Eα1: escaped + 155-keV x ray

Eα2=10259 keV, Δt2=71 ms, assigned to 268Mt

Eα3=9475 keV, Δt3=98 ms, assigned to 264Bh

Eα4=1969 keV (escaped), Δt4=1.969 s, assigned to 260Db

Event #2 (1995Ho04):

Eα1=4612 keV (escaped), Δt1=0.696 ms, assigned to 272Rg

Eα2=10097 keV, Δt2=171 ms, assigned to 268Mt

Eα3=9618 keV, Δt3=334 ms, assigned to 264Bh

Eα4=9146 keV, Δt4=953 ms, assigned to 260Db

Event #3 (1995Ho04):

Eα1=10820 keV, Δt1=2.042 ms, assigned to 272Rg

Eα2=10221 keV, Δt2=72 ms, assigned to 268Mt

Eα3=9621 keV, Δt3=1.452 s, assigned to 264Bh

Eα4=9200 keV, Δt4=573 ms, assigned to 260Db

Eα5=8463 keV, Δt5=66.3 s, assigned to 256Lr

2002Ho11: 209Bi(64Ni,n), E=320 MeV reaction at GSI using UNILAC and SHIP separator with three additional correlated decay chains observed:

History of three events in 2002Ho11:

Event #1: energy of the evaporation residue=41.76 MeV (2002Ho11):

Eα1=3503 keV (escaped), Δt1=3.36 ms, assigned to 272Rg

Eα2=10294 keV, Δt2=4.23 ms, assigned to 268Mt

Eα3=9385 keV, Δt3=944 ms, assigned to 264Bh

Eα4=9156 keV, Δt4=364 ms, assigned to 260Db

Eα5=8465 keV, Δt5=55.8 s, assigned to 256Lr

Event #2: energy of the evaporation residue=36.55 MeV (2002Ho11):

Eα1=11008 keV, Δt1=1.38 ms, assigned to 272Rg

Eα2=6953 keV, Δt2=7.32 ms, assigned to 268Mt

Eα3=9514 keV, Δt3=2.99 s, assigned to 264Bh

Eα4=1706 keV (escaped), Δt4=14.98 s, assigned to 260Db

Eα5=877 keV (escaped), Δt5=47.0 s, assigned to 256Lr

Event #3: energy of the evaporation residue=39.19 MeV (2002Ho11):

Eα1=11046 keV, Δt1=2.70 ms, assigned to 272Rg

Eα2=765 keV (escaped), Δt2=37.14 ms, assigned to 268Mt

Eα3=9113 keV, Δt3=3.01 s, assigned to 264Bh

Eα4=9129 keV, Δt4=4.06 s, assigned to 260Db

Eα5=8423 keV, Δt5=20.6 s, assigned to 256Lr

5 event average (including data points from 1995Ho04) for t1=2.3 ms. Two event average (two data points indicating redundancy within current experiment) for Eα=11027 keV. At a beam energy of 320 MeV, a total of 3.3×1018 projectiles were delivered over 5 events from both experiments corresponding to an average cross-section of 2.9 pb +19-13.

2004Fo08: cold fusion experiment done at LBNL-Berkeley using the 208Pb(65Cu,n),E=326.9 MeV (E*=13.2 MeV) reaction, 65Cu{15+ beam provided by the 88-inch cyclotron, and reaction products separated using Berkeley gas-filled separator (BGS). One EVR-α1-α2-α3-α4-α5 correlated decay chain was observed and attributed to the decay of 272Rg. The cross-section was estimated to be 1.7 pb +39-14.

Energy of evaporation residue=28.58 MeV (2004Fo08):

Eα1=11042 keV, Δt1=0.263 ms, assigned to 272Rg

Eα2=10114 keV, Δt2=12.6 ms, assigned to 268Mt

Eα3=993 keV (escaped), Δt3=1.16 s, assigned to 264Bh

Eα4=9416 keV, Δt4=1.45 s, assigned to 260Db

Eα5=8613 keV, Δt5=3.16 s, assigned to 256Lr

2004Mo26: 209Bi(64Ni,n),E=320,323,326 MeV using the RIKEN linear accelerator (RILAC) and the gas filled recoil ion separator GARIS. The detector system consisted of two foil detectors with micro-channel plates (MCP’s) and a Si semi-conductor (SSD) box. The detectors were used for purpose of time-of-flight and, in anti-coincidence mode, as a veto for signals coming from the MCP’s. α total of 11 correlated decay chains were observed at 323 MeV, three at 320 MeV, and none at 326 MeV. The cross-sections were measured as: 2.6 pb +23-15 for 320 MeV, 2.5 pb +12-9 for 323 MeV, and <1.1 pb at 326 MeV. Probability for accidental signals was determined to be 2.3×10-8, with estimates given for different types of events. See also related article 2004Mo14.

History of 14 events in 2004Mo26, projectile energies given in parentheses, when uncertain due to target deterioration:

Event #1: E=(323 MeV); tof=48.3 ns; E(EVR)=33.1 MeV (2004Mo26):

Eα1=11.08 MeV, Δt1=11.0 ms, assigned to 272Rg

Eα2=10.36 MeV, Δt2=9.20 ms, assigned to 268Mt

Eα3=9.81 MeV, Δt3=1.38 s, assigned to 264Bh

Eα4=9.17 MeV, Δt4=1.93 s, assigned to 260Db

Eα5=8.39 MeV, Δt5=11.9 s, assigned to 256Lr

Event #2: E=(323 MeV); tof=45.8 ns; E(EVR)=33.0 MeV (2004Mo26):

Eα1=11.04 MeV, Δt1=4.42 ms, assigned to 272Rg

Eα2=10.68 MeV, Δt2=13.0 ms, assigned to 268Mt

Eα3=9.60 MeV, Δt3=1.45 s, assigned to 264Bh

Eα4=9.05 MeV, Δt4=10.9 s, assigned to 260Db

Eα5=8.37 MeV, Δt5=21.9 s, assigned to 256Lr

Event #3: E=(323 MeV); tof=46.5 ns; E(EVR)=33.2 MeV (2004Mo26):

Eα1=11.56 MeV, Δt1=14.9 ms, assigned to 272Rg

Eα2=1.12 MeV (escaped), Δt2=122 ms, assigned to 268Mt

Eα3=9.85 MeV, Δt3=21.8 ms, assigned to 264Bh

Eα4=9.34 MeV, Δt4=0.505 s, assigned to 260Db

Eα5=8.65 MeV, Δt5=33.5 s, assigned to 256Lr

Event #4: E=323 MeV; tof=47.3 ns; E(EVR)=30.5 MeV (2004Mo26):

Eα1=11.25 MeV, Δt1=1.42 ms, assigned to 272Rg

Eα2=10.43 MeV, Δt2=36.6 ms, assigned to 268Mt

Eα3=9.66 MeV, Δt3=1.87 s, assigned to 264Bh

Eα4=9.40 MeV, Δt4=1.52 s, assigned to 260Db

Eα5=3.12 MeV (escaped), Δt5=46.8 s, assigned to 256Lr

Event #5: E=323 MeV; tof=46.3 ns; E(EVR)=31.6 MeV (2004Mo26):

Eα1=10.82 MeV, Δt1=7.11 ms, assigned to 272Rg

Eα2=10.29 MeV, Δt2=0.715 ms, assigned to 268Mt

Eα3=9.57 MeV, Δt3=0.543 s, assigned to 264Bh

ESF=231 MeV, Δt4=1.71 s, assigned to 260Db

Event #6: E=323 MeV; tof=47.5 ns; E(EVR)=32.7 MeV (2004Mo26):

Eα1=11.31 MeV, Δt1=2.82 ms, assigned to 272Rg

Eα2=10.78 MeV, Δt2=44.0 ms, assigned to 268Mt

Eα3=9.58 MeV, Δt3=0.442 s, assigned to 264Bh

Eα4=8.81 MeV, Δt4=48.5 s, assigned to 260Db

Event #7: E=323 MeV; tof=47.5 ns; E(EVR)=32.7 MeV (2004Mo26):

Eα1=10.58 MeV, Δt1=1.17 ms, assigned to 272Rg

Eα2=10.35 MeV, Δt2=38.3 ms, assigned to 268Mt

Eα3=9.31 MeV, Δt3=3.6 ms, assigned to 264Bh

Eα4=9.01 MeV, Δt4=4.87 s, assigned to 260Db

Eα5=8.50 MeV, Δt5=45.8 s, assigned to 256Lr

Event #8: E=323 MeV; tof=46.0 ns; E(EVR)=31.1 MeV (2004Mo26):

Eα1=10.96 MeV, Δt1=8.89 ms, assigned to 272Rg

Eα2=2.76 MeV (escaped), Δt2=26.2 ms, assigned to 268Mt

ESF=208 MeV, Δt3=0.967 s, assigned to 264Bh

Event #9: E=323 MeV; tof=47.0 ns; E(EVR)=31.1 MeV (2004Mo26):

Eα1=11.06 MeV, Δt1=5.11 ms, assigned to 272Rg

Eα2=10.43 MeV, Δt2=19.1 ms, assigned to 268Mt

Eα3=9.50 MeV, Δt3=1.34 s, assigned to 264Bh

Eα4=9.10 MeV, Δt4=3.69 s, assigned to 260Db

Eα5=8.41 MeV, Δt5=48.5 s, assigned to 256Lr

Event #10: E=320 MeV; tof=47.5 ns; E(EVR)=31.0 MeV (2004Mo26):

Eα1=10.21 MeV, Δt1=1.00 ms, assigned to 272Rg

Eα2=10.03 MeV, Δt2=8.81 ms, assigned to 268Mt

ESF=206 MeV, Δt3=4.93 s, assigned to 264Bh

Event #11: E=320 MeV; tof=47.8 ns; E(EVR)=32.2 MeV (2004Mo26):

Eα1=10.85 MeV, Δt1=0.773 ms, assigned to 272Rg

Eα2=10.34 MeV, Δt2=32.4 ms, assigned to 268Mt

Eα3=8.87 MeV, Δt3=1.91 s, assigned to 264Bh

Eα4=8.50 MeV, Δt4=21.0 s, assigned to 260Db

Event #12: E=320 MeV; tof=47.0 ns; E(EVR)=32.4 MeV (2004Mo26):

Eα1=11.00 MeV, Δt1=6.92 ms, assigned to 272Rg

Eα2=10.58 MeV, Δt2=35.5 ms, assigned to 268Mt

Eα3=9.34 MeV, Δt3=1.00 s, assigned to 264Bh

Eα4=9.14 MeV, Δt4=1.14 s, assigned to 260Db

Eα5=8.47 MeV, Δt5=38.6 s, assigned to 256Lr

Event #13: E=323 MeV; tof=44.8 ns; E(EVR)=28.9 MeV (2004Mo26):

Eα1=11.01 MeV Δt1=6.84 ms, assigned to 272Rg

Eα2=9.40 MeV Δt2=37.2 ms, assigned to 268Mt

Eα3=9.56 MeV Δt3=1.23 s, assigned to 264Bh

Eα4=8.29 MeV Δt4=0.334 s, assigned to 260Db

Event #14: E=323 MeV; tof=47.8 ns; E(EVR)=33.0 MeV (2004Mo26):

Eα1=11.08 MeV, Δt1=4.46 ms, assigned to 272Rg

Eα2=10.28 MeV, Δt2=3.35 ms, assigned to 268Mt

Eα3=9.63 MeV, Δt3=0.81 s, assigned to 264Bh

Eα4=9.13 MeV, Δt4=2.42 s, assigned to 260Db

Eα5=8.63 MeV, Δt5=6.85 s, assigned to 256Lr

For theoretical studies, consult Nuclear Science References (NSR) database at NNDC, BNL for 58 primary references dealing with the half-lives and other aspects of nuclear structure in this mass region

Q-value: Estimated uncertainty (2017Wa10): ΔS(p)=250.

Q-value: S(n) from 1997Mo25. S(p) and Q(α) from 2017Wa10

Q-value: S(2p)=2980 620, Q(εp)=4380 400 (syst,2017Wa10). S(2n)=15630 (1997Mo25,theory)

Q-value: Other Q(α)=11150 35 from Eα=10986 keV 35 (2004Mo26, unweighted average of all the events).

  0 3.8 ms +14-8 
% α ≈ 100

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Additional Level Data and Comments:

  0 3.8 ms +14-8 
% α ≈ 100
Only the α-decay mode observed in 21 decay chains from three different laboratories.
E(level): Only the α-decay mode observed in 21 decay chains from three different laboratories.

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