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Odd Isotope half-life help

  1. Sep 25, 2014 #1
    The Sigma database at Brookhaven lists seven isotopes as fission products for which I can't find half-life data. I've tried nea6287-JEFF-20-1, the NuDat_2 web site, Nuclear Wallet Cards and Wikipedia. Anybody have any other ideas?
    The isotopes are
    74-As-m1
    85-Se-m1
    86-Br-m1
    109-Ru-m1
    109-Rh-m1
    143-Xe-m1
    162-Tb-m1
     
  2. jcsd
  3. Sep 25, 2014 #2

    mathman

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  4. Sep 25, 2014 #3
    Ooh, so close. Got the first one on the list, then went 0 for 6.

    Thanks.
     
  5. Sep 26, 2014 #4
    You may want to check out these databases. Here is a list of all the isotopes in the ENDF/B-VII.1 decay sublibrary. A quick look shows it has at least some of the isotopes. It doesn't say anything about meta-stable states for the ones I looked at so hopefully you mean m1 is the ground state instead of first excited state.
     
  6. Sep 27, 2014 #5
    Sorry. I do mean the first excited state. None of the isotopes on my list show up on the list you provided.
    These aren't exactly rare fission products. The max yield for 109-Ru-m1 is over 1%, albeit for 142-Am-m1 as the fuel. For 85-Se-m1 it's ~0.5% for 233-U and 235-U. I expect they aren't much of a problem in the waste stream because of short half-lives. I'll mention them as a caveat in my assumptions.

    Thanks, though.
     
  7. Sep 28, 2014 #6

    mathman

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    http://atom.kaeri.re.kr/ton/
    Did you look here? I got the results for all (I am not sure what you mean by m1).
    I got for the particular isotopes: As 17.77 days, Se 31.7 s, Br 55.1 s, Ru 34.5 s, Rh 80 s, Xe 0.30 s, Tb 7.60 min.
     
  8. Sep 28, 2014 #7
    To mathman, re http://atom.kaeri.re.kr/ton/
    (This forum doesn't indent enough!)
    Yes I visited the Korean site, twice. On my second visit I followed one reference URL back to a UK paper on PDF at Brookhaven. A bit roundabout, but very worldly. The PDF topic is not really half-lives, but they use them to describe the excited states. The PDF doesn't label them m1, m2, etc. I got the 74-As-m1 half-life from the Korean site, then 109-Ru-m1 from the PDF. Four more to go.
    The numbers you gave above are for the ground state. I'm looking for the first excited state (-m1).
     
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