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Cern Mass Produces Anti-Hydrogen
Izeickl writes "The BBC is reporting Here about scientists in the Cern particle accelerator in Geneva, Switzerland have mass produced over 50,000 atoms allowing them to test basic Physics using them, however "Harvard physicist Gerald Gabrielse said: "Our long experience with these very difficult experiments warns that antihydrogen may not have really been produced.""
From the horses mouth :-) Athena, the guys who did it
Nature.com article(PDF)
home page of the experiment
My Aurora : http://www.youtube.com/watch?v=o91ZsGwJYyg
FB : https://www.facebook.com/TanveersPhotography
1 mole of gas at RTP fills 24 litres (or was it 12?) and there are 6.022*10^23 atoms in a mole. So, assuming a handful is 10ML, it'll be have in the order of 20-21 zeros.
Put another way, about 16 orders of magnitude over 50,000. But these are rough estimates from memory.
Actually in vacuum hydrogen would fall down. And those anti-matter particles are created in vacuum (held in place by strong electromagnets).. but they probably wouldn't "fall up", because the only thing that differs between particle and antiparticle is it's spin. (it's not really the speed particle is rotating at.. but more like internal momentum).
IMO, CERN's press release is much more informative than the BBC article.
But CERN's intranet is also readily searchable and apart from the technical details on the new LHC accelerator (which are publically available and make great geek reading) I also find
this further information on the AD (Antiproton Decelerator), which makes the trapping of antiparticles possible.
There's a simple and to-the-point description of Antihydrogen at the Wikipedia.
Bizarrely, the person responsible for the original submission is typing this sentence right now. Thankfully, brighter people have improved upon it somewhat since then... :)
Insert witty sig about inserting witty sig here, here.
Actually, Hindenberg was a general and a politician, not any sort of scientist. You may mean Herr Zeppelin...
because the only thing that differs between particle and antiparticle is it's spin
that's wrong, it's the electric charge that is opposite for particles and their antiparticles. The total spin (magnitude of spin) is the same for both and the actual spin vector is not a fixed property for a particle (except when it's zero).
You say they make very ffew antiprotons from all that power, and I guess that in human terms that is correct. However, I'm looking at live readouts at the Tevatron status, and there are currently 48.38*10^10 anti-protons in the antiproton storage ring you speak of, and another 246.92*10^9 in the Tevatron itself.
Just you give you a sense of how much antimatter is produced. Cern didn't produce much antimattter at all with these 50,000 atoms. Fermilab doesn't produce any antiatoms because they have no use for them. Only negative antiprotons (pbars) are of any use.
Don't Bogart the fish sticks
for a handful the hand would have to be really, really small. By the way, has anybody thought about the fact that even if we could produce antihydrogen in large quantities, it would be pretty useless as a source of energy. Since its charge would be neutral, you couldn't contain it magnetically. You would have to use antiprotons or an anti-element with a positive or negative charge..
In comparing the quantities, you should keep in mind that the storage rings you are talking about have very "hot" (high kinetic energy) antiprotons.
The real achievement is to cool the antiprotons down to about 15 K, and combining them with positrons. The yield of that whole process is very low. I.e., you need large quantities of hot antiprotons to produce 50k atoms of "cold" antihydrogen.
As a member of the team that produced antihydrogen I might want to add for information that the author of that comment, Gabrielse, is the leader of a directly competiting team that has been pursuing the same goal using a different approach.
Suspension between the superconducted charged magnets.
"The more you know, the less you understand."
This link describes how the ATRAP collaboration cools the ingredients of Antihydrogen.