[Dan1195]

A new paper was just released, http://xxx.lanl.gov/PS_cache/arxiv/pdf/0904/0904.1093v1.pdf, detailing the production of ^266,267Bh. The main purpose was to confirm the daughter decay properties of ²⁷⁸113. The data seems to confirm the previous studies done. Unfortunately because only data from after the beam was turned off was considered the lifetimes of the Bh atoms themselves were not obtained.

Only interesting thing I noticed the last two chains, 31 & 32, which were unable to be assigned. Both had an 8090 keV alpha follow by a 2-3 minute SF. Obviously that alpha was not from Bh (or Db daughters). The only thing that is a possibility is the alpha is from the EC daughter of ²⁶⁷Bh, ²⁶⁷Sg and the SF is from the g.s. of ²⁶³Rf. From Phys Rev Lett 100, 132503 (2008), ²⁶⁷Sg has a small alpha branch, with one 8200 keV alpha observed assigned to ²⁶⁷Sg which decays to an apparent isomeric state of ²⁶³Rf with an 12 second lifetime. If this is this case then ^261,263Rf both have a longer lived g.s. along with an isomeric state decaying mostly by SF. The 8090 alpha goes to the g.s. and the 8200 goes to the isomer. Would be important to note that since ^263,265Sg have isomers with similar lifetimes, ²⁶⁷Sg may also!!

Note than the SF of ²⁶⁷Sg would not appear in this study as they were looking for a-a or a-SF correlations, which EC>SF does not. Also, since the maximum correlation time analyzed was 300 seconds, other ²⁶³Rf decays could have been missed.

Needless to say better data on ²⁶⁷Sg is needed to confirm this possibility