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Specialty Chemistry Forums => Nuclear Chemistry and Radiochemistry Forum => Topic started by: Dan1195 on May 03, 2008, 09:40:21 PM

Title: decay chain question
Post by: Dan1195 on May 03, 2008, 09:40:21 PM
I was looking at some of the decay chains of the 277112->265Sg series as well as for 287114 and was wondering how does it get determined if an SF termination of a decay chain is from nuclide X or its daughter Y (with the alpha decay of X missing) in the case where daughter lifetime is less than that of the parent.

The GSI 283112 data shows a significant SF branch. None of the Dubna data shows this. They do however have have 4 chains with long SF lifetimes all assigned to 279Ds following a missed alpha.

In 265Sg (state populated from 269Hs as opposed to direct production) also has 4 cases where an alpha was apparently missed and relatively long SF was assigned to the SF decaying isomer of 261Rf. I bring up 265Sg because No SF branch has been measured here. But SF systematics for odd Neutron Sg isotopes would indicate a partial SF half-life of between 30-105 seconds (partial SF half lives for 261,267Sg which should have been detected with the number of atoms observed.

Would seem best things one would have to go on is the expectation of number of missed alphas based on detector efficiency.
Title: Re: decay chain question
Post by: gippgig on May 03, 2008, 10:39:56 PM
There is no way to be certain of this and if only a single decay chain is observed this is a very real possibility (i.e., 287115). The more decay chains that are observed without an alpha the less likely this becomes. Some papers (don't remember which offhand) have given estimates of how likely this is to have occurred.