occam Posted June 17, 2008 Posted June 17, 2008 I have been doing some analysis work on isotope data, and got some results which dont seem to appear in the literature. I attach an extract from my findings Any comments please?
Klaynos Posted June 17, 2008 Posted June 17, 2008 They all look to be results of binding energy that can be found from the semi-empirical mass formula... :|
swansont Posted June 17, 2008 Posted June 17, 2008 I don't see anything surprising in there, other than not really believing a graph having data associated with Z=285 and the vicinity. Any specific questions?
occam Posted June 17, 2008 Author Posted June 17, 2008 They all look to be results of binding energy that can be found from the semi-empirical mass formula... :| The only binding energy graphs are 6.5b; 6.6b; and 6.6e I don't see anything surprising in there, other than not really believing a graph having data associated with Z=285 and the vicinity. Any specific questions? Ah! Graph 6.1 should have read total nucleon A number. Thank you, I will amend Any specific questions? Some have queried the finding • There is only one fully stable “Z” isotope for a given atomic Nucleon number “A” and there are only 194 of these. Have you any problem with this?
swansont Posted June 17, 2008 Posted June 17, 2008 Some have queried the finding • There is only one fully stable “Z” isotope for a given atomic Nucleon number “A” and there are only 194 of these. Have you any problem with this? Since it's not true, then yes. I didn't realize this was being claimed.
occam Posted June 18, 2008 Author Posted June 18, 2008 The main data came from the tables of Isotopes from Wikipedia http://en.wikipedia.org/wiki/Isotopes_of_hydrogen etc To this I have identified the decay mode, from http://periodictable.com/Isotopes/001.3/index.p.full.dm.html etc. The upload module would not let me attach the working spreadsheet, or an extract in doc format, so I hope you can decipher this. If not send me a message with a contact e-mail, and I will send you the original file. Graham
swansont Posted June 18, 2008 Posted June 18, 2008 You haven't made it clear what you're trying to prove. As far as the "one stable Z for a given A" this is trivially falsified. Fe-58 and Ni-58 are stable. Se-80 and Kr-80 are stable. Sr-86 and Kr-86 are stable. And there are more.
occam Posted June 19, 2008 Author Posted June 19, 2008 As far as the "one stable Z for a given A" this is trivially falsified. Fe-58 and Ni-58 are stable. Se-80 and Kr-80 are stable. Sr-86 and Kr-86 are stable. And there are more. I agree these pairs are listed as stable in most general sources but as I wanted the decay modes I consulted periodictable.com published by Wolfram research, which I presume is a reputable source, and found additional data, for instance the page http://periodictable.com/Isotopes/028.58/index.p.full.dm.html shows 58Ni has a 2B+ decay of -118.68keV to 58 Fe and http://periodictable.com/Isotopes/034.80/index.p.full.dm.html shows 80 Se is 2B- decay 132.56keV to 80Kr and http://periodictable.com/Isotopes/036.86/index.p.full.dm.html 86Kr is 2B- decay 1258.01keV to 86 Sr. And so on. Having crawled through all 3177 listed isotopes, I found that these additional decays accounted for all the duplicates in the A numbers, leaving just one Z number for each which is fully stable (according to Wolfram). In 14 cases between 1 and 208. there is no stable Z number. Which is why I raised the question (in several forums). It appears that no one has noticed this before.
swansont Posted June 19, 2008 Posted June 19, 2008 The decays are possible because of the energy difference — in any list, only one value can be smallest. But are these decays actually observed?
occam Posted June 20, 2008 Author Posted June 20, 2008 But are these decays actually observed? I think they must be. Although the isotope tables in Wikipedia show these as “stable” the remark is qualified by a very long half-life figure, I cannot imagine that these would be included without some evidence. However it looks like I’m going to have to do more research for supporting evidence.
swansont Posted June 20, 2008 Posted June 20, 2008 The wikipedia entry on double-beta decay says otherwise http://en.wikipedia.org/wiki/Double_beta_decay In most cases, the double-beta decay is so rare as to be nearly impossible to observe against the background of other radiation.
occam Posted June 22, 2008 Author Posted June 22, 2008 In most cases, the double-beta decay is so rare as to be nearly impossible to observe against the background of other radiation.[/i] And of course you have answered your question. It may be rare, but for these isotopes the preobability of decay is greater than zero. All I have done is eliminate these from the list so that only the isotopes with zero decay probability remain.(which is where I came in!).
John Cuthber Posted June 22, 2008 Posted June 22, 2008 OK, how fast is proton decay? Anything slower than that might as well be stable.
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