New Element 115

[tyr_13]

Ok, serious possibly stupid question here about patchium... I mean, ununpentium.

When you're creating the stuff, and it decays so quickly, how do you know that you've created an actual atom? Couldn't what they're seeing be just byproducts of the impact of the two atoms they slammed together?

I'm surprised that this hasn't been answered yet and I hope someone more knowledgeable will correct my inevitable mistakes.

They're using two elements for which the decay products are known. Not only are these decay products the elements into which they decay, but radiation given off by the decay. These would be detected commonly throughout the bombardment. (I believe they were bombarding Americium with another element.) The combined decay products known did not match all the combined decay products actually produced. For example, the alph rays and x ray signature of the products didn't match the known ones. If I remember correctly x ray signature for most elements is very distinct and can't simply be combined to produce the same signature as another element. Two hydrogen signatures don't produce the same signature as helium for example. This same concept is one way to identify the composition of materials from a distance.

Now that I've gotten it wrong, someone will be along to correct me.

 

[rjh01]

This is not a new element. Here is a video made in 2008 about it http://www.youtube.com/watch?v=gCt5WK2OVp0.

 

[tyr_13]

2008 is pretty new for an element. Besides, with it's confirmation it's now pretty close to being officially added.

 

[TheDoLittle]

Why not Zoidbergium?

 

[ben m]

When you're creating the stuff, and it decays so quickly, how do you know that you've created an actual atom? Couldn't what they're seeing be just byproducts of the impact of the two atoms they slammed together?

"So quickly" is actually pretty slow by the standards of a particle detector. It's enough time, in fact, to transfer the new atom from the target chamber (where it was created) to a separate detector chamber (where it decays, and the decay is detected.)

The transport system, called a "recoil separator", is designed to block any random debris from non-fusion-like collisions, but to collect nuclei with the properties expected from a successful fusion reaction. You transport the new nucleus from the target-chamber to a detector-chamber and crash it into the surface of the detector. There, you wait for it to decay (in fact, you might turn off the accelerator while you wait) and start counting the alphas and the time-delays between them. You generally expect a few alpha decays (5-10 MeV each) followed by a spontaneous-fission (200 MeV). You detect those all happening in the same spot on your detector, and it's pretty certain that they all came from a single parent.

There's a bit of work to do to patch together the observed decay-chains ("OK, we saw an atom arrive, which emitted an 8 MeV alpha after 100ms, then a 10 MeV alpha after 4ms, then a fission after 1.1s") and figure out what the parents and daughters were. You certainly need more than one event do do this with. Ideally, you wind up seeing a very familiar pattern in the energies and times ("hey, those last three alphas looked just like the 276 Meitnerium chain"). Once the decay products get a bit longer-lived, you can also do chemistry on them. In the case of ununpentium, the Russians confirmed that the final (16-hour) decay was a dubnium isotope by chemical methods. They pull out the implanted target *before* the final fission is seen, run it through some chemical processing steps, and show that the eventual fission occurs in *this* beaker (containing the stuff that precipitates like dubnium) rather than this other beaker (containing the stuff that precipitates like lawrencium) and so on. Neat experiments.

 

[patchbunny]

Kewlies!

 

[catsmate]

Yeah, so if they're asking the Russians it's probably---what, Sakharov or Kurchatov? The most famous physicist associated with Lund is probably Rydberg.

ETA: Or Zeldovich! Zeldovicium (Zv) would be neat.

Perhaps Ulsterium or Unionity............
Well it was a joint Dubna/LLNL team who did the original work in 2008-10 so they'll be involved also. However there already are Dubnium, Livermorium, Flerovium and Lawrencium so maybe the Swedes will get input; Rydbergium or Siegbahnium perhaps.

I'm surprised that this hasn't been answered yet and I hope someone more knowledgeable will correct my inevitable mistakes.

I'll try, though I'm a amateur with a physics background.

They're using two elements for which the decay products are known.

Usually one of the elements used is stable, i.e. the current method to produce Uup is
²⁴³₉₅Am + ⁴⁸₂₀Ca --> ^291−x₁₁₅Uup + n ¹₀ where x is 2, 3 or 4
The Uup then decays (half-life is <1s) by alpha emission into a corresponing atom of Uut, which also decays......and so on. The decay reaction, or rather their products, are detected and as the chain gets into the better known area of the periodic table, around Hassium-Dubnium, the characteristics of the decay products are well known.

Not only are these decay products the elements into which they decay, but radiation given off by the decay. These would be detected commonly throughout the bombardment. (I believe they were bombarding Americium with another element.) The combined decay products known did not match all the combined decay products actually produced. For example, the alph rays and x ray signature of the products didn't match the known ones. If I remember correctly x ray signature for most elements is very distinct and can't simply be combined to produce the same signature as another element. Two hydrogen signatures don't produce the same signature as helium for example. This same concept is one way to identify the composition of materials from a distance.

Now that I've gotten it wrong, someone will be along to correct me.

No, that's pretty accurate. The main problem is the tiny chance of a successful production reaction, you're talking single figure atoms. While there's quite a bit of 'noise' from your Americium target decaying.

This is not a new element. Here is a video made in 2008 about it http://www.youtube.com/watch?v=gCt5WK2OVp0.

Kewlies!

Actually there's some evidence it was first produced way back in 2003. However it's only now that IUPAC considers the evidence of synthesis strong enough to accept.

 

[tyr_13]

SNIP

Thanks!

 

[L.Y.S.]

How about Metallicum sense it's a heavy metal, geddit?

 

[Slimething]

Why not Zoidbergium?

Love it but it should be all one word Ynotzoidbergium. Please forgive the phonetic substitution.

 

[TheDoLittle]

Love it but it should be all one word Ynotzoidbergium. Please forgive the phonetic substitution.

/thread

 

[Andrew Wiggin]

Thatseaborgfellawasarealstandupguyium.

A.

 

[Reivax]

Isn't the island of stability supposed to be up around 127 or so?

I'm extremely excited about this theoretical 'island of stability'. Sounds like some of my sci-fi dreams can be realized (hopefully in our lifetime).

 

[Polaris]

How about Metallicum sense it's a heavy metal, geddit?

No, but it'd be a good name if James Hetfield launched a porn site.

 

[CMRTIXPS57]

Let's see. Pokemon number 115 is Kangaskhan. The 115th episode of the series Viva Las Lapras. 1+1+5 = 7 which is a prime number. 1x1x5=5 which is also a prime number. However (1+1) x 5 = 10 which is not a prime number. Furthermore, page 115 of this book I am reading has pictures.

Therefore it is only logical to name the 115th element Bobby.

 

[Soapy Sam]

Cut the prefixes.
Call it "Ium".