[Mitch]

I can finally talk about ²⁶⁴Sg since Gregorich's paper came out this week. The paper is cool for many reasons and not only because I'm a co-author. The paper recounts the Seaborgium-264 discovery by our group earlier this year from the nuclear reaction of ²³⁸U(³⁰Si,4n)²⁶⁴Sg. We observed a total of 5 events of Seaborgium. The events are summarized in the figure below.


Taken from: http://dx.doi.org/10.1103/PhysRevC.74.044611

It sucks to read a table, like the one above, to try and figure out general decay properties of a nuclide. So instead of reading through all the known literature values for a nuclide, we'll condense the above information into a little box like this one I made (shown below).



The percentage of green signifies the probability it will undergo spontaneous fission. For ²⁶⁴Sg it will undergo spontaneous fission 100% of the time, thus the box is completely filled green. These decay boxes are traded between nuclear chemists as kids trade with Pokemon cards. All nuclear chemists want to keep up to date on the latest decay systematics for any given nuclide, but it's a pain to always track them down and then update your existing files with new data and making sure you didn't miss any other data from the literature. So I'll most likely use this blog as one mechanism I'll incorporate to keep track of new data.

Very recently Nishio also published some of his results regarding Sg-264.

Taken from: http://dx.doi.org/10.1140/epja/i2006-10091-y

Nishio calculated a half-life of 120.7 ms from 3 atoms detected. Summing Nishio's work with our experiment we can have a better value for ²⁶⁴Sg true decay properties, shown below.



Enjoy the latest trading card.

Mitch

[FeLiXe]

so how do you make seaborgium? in a particle accelerator? and where do you get a particle accelerator from?

[Mitch]

so how do you make seaborgium? in a particle accelerator? and where do you get a particle accelerator from?

You can make it from the following reaction ²³⁸U(³⁰Si,4n)²⁶⁴Sg, and there are only a few accelerators in the world that would be able to do this specific reaction, and even fewer places where you could do the above reaction and separate the nuclide of interest from all the other junk produced in the process.

[FeLiXe]

how many accelarators are there in the world? I thought it would be like CERN, Fermilab, and Stanford. And maybe the one where they made ununoctium. But I didn't even know about that one until they made ununoctium (I know real nuclear chemists wouldn't say that).

which accelerator do you use?

[Mitch]

CERN, Fermilab, and Stanford

Those are all high energy physics accelerators. The real accelerators where you can do nuclear chemistry with can be found all over the place, like Berkeley, Michigan, Texas A&M, knoxsville Tennessee, and several others. You can't make element 118 at high energy accelerators, you need a low energy accelerator like the one at Berkeley for that. The one at Berkeley can accelerate reasonably large projectiles, so it is more suitable to use it for exploring elements >104 for instance.

[FeLiXe]

ok, thanks. I don't think I've heard of those accelerators before.

[pantone159]

Texas A&M

What's the A&M accelerator like?  Is it in College Station?  I'm curious because it is close to home.

[Mitch]

I've never been there.

[Dan1195]

A lot of new information has come out within the past year regarding the decay properties of Sg 262-267.  The above paper, combined with the new Seaborgium 265-267 data (see http://www.ha.physik.uni-muenchen.de/heaviest_atoms/talks/Dvorak.pdf for info) allows us to revisit the decay properties of Sg.

First, we now have a clear half-life pattern for Even-even isotopes of Seaborgium:

Sg-258: 2.8 ms
Sg-260: 7.2 ms
Sg-262: 15 ms
Sg-264: 37 ms
Sg-266 360 ms  (all of the earlier alpha chains assigned to Sg-266 now appear to be in error)

This Shows the increase in SF half-life as the deformed N=162 shell enclosure is approached.
Fission hinderance for the odd N Seaborgium isotopes is about 500-1000 based on Sg-263 & 267 data.