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LHC Scientists Create and Capture Antimatter
Velcroman1 writes "Scientists at the Large Hadron Collider have created antimatter in the form of antihydrogen, demonstrating how it's possible to capture and release it. The development could help researchers devise laboratory experiments to learn more about this strange substance, which mostly disappeared from the universe shortly after the Big Bang 14 billion years ago. Trapping any form of antimatter is difficult, because as soon as it meets normal matter — the stuff Earth and everything on it is made out of — the two annihilate each other in powerful explosions. 'We are getting close to the point at which we can do some classes of experiments on the properties of antihydrogen,' said Joel Fajans, a University of California, Berkeley professor of physics, and LBNL faculty scientist. 'Since no one has been able to make these types of measurements on antimatter atoms at all, it's a good start.'"
IANAP.. but..
I think the temporary capture of antiprotons and antielectrons has been achieved before, since it is relatively easy. It is the significant-duration capture of antihydrogen (i.e. antiproton + antielectron, forming an electrically neutral 'anti-atom') which is new ( ? ). Please correct, and scold, me if I am wrong.
ALPHA project is NOT a part of LHC. It is one of many other project at CERN that does not have much to do with LHC.
Note that production and capture of antihydrogen is not new. There's been prior work trying to use it to test for possible CPT violations. See for example hussle.harvard.edu/~atrap/Papers/2010/AntihydrogenPhysicsToday.pdf, http://adsabs.harvard.edu/abs/2005APS..DPPFP1058V and http://www.physics.harvard.edu/Thesespdfs/speck.pdf.
Antiprotons are relatively low-energy phenomena, being produced at 1 GeV. The LHC is a HIGH-energy facility, using energies 7000 times higher. Using the LHC to make antiprotons would be ridiculous overkill and counter-productive, since the ALPHA experiment needs antihydrogen at rest. Not every experiment at CERN uses the LHC. In this case, the cool bit of machinery is the Antiproton Decelerator (AD) and ALPHA's magnetic trapping system.
Stopped reading after the first sentence...
Scientists working on the big bang machine in Geneva have done the seemingly impossible: create, capture and release antimatter.
The "machine" in question does have a name, you know?
BBC News also has coverage,
http://www.bbc.co.uk/news/science-environment-11773791
The positive particles (Protons) also have far more mass than negative particles (Electrons)
Protons are not antimatter electrons. Positrons are antimatter electronis, and they do have the same mass as electrons. The antimatter opposite of a Proton is an anti-proton. The naming system is inconsistent, probably because the original creators of the names did not know about antimatter.
No, you are correct. The only difference we *expect* to see from anti-matter is that the electrical charge is reversed. The mass, spin states, etc. should all be the same.
What the scientists are looking for is the slim chance that anti-matter is different in some way. That would be exciting, because it would tell us something new.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
I'm not trying to rag on Fox News here, but why link them and not CERN's press release page?
Clicky
No sig for you!!
perhaps a better link: http://newscenter.lbl.gov/news-releases/2010/11/17/antimatter-atoms/
Please use this link http://www.nature.com/news/2010/101117/full/468355a.html it was the original. Tired of the FOX News links.
They use the magnetic moment of the antihydrogen. They trap it for about 1/6 of a second, which isn't very long, considering we can trap charged antiparticles for weeks in Penning-Malmberg traps. But it's still impressive.
At http://cerncourier.com/cws/article/cern/30577 you can read a slightly sarcastic piece about what it would take to hold the quantities that Dan Brown used in his books.
Nice wry write-up - I like the details..
Insert
The space between our galaxy and the next one over is not empty. It contains extremely rarified gas. If the next galaxy was made of antimatter there would be a transition region where matter and antimatter would mix, collide, and emit easily detected gamma rays.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Not likely, we have a special image of the universe 400,000 years after it formed, the CMB from the "surface of last scattering" which shows that it was matter dominated (and very uniform) when it was 1/1100th it's present size.
No but I wish it were possible to annihilate all the inaccuracies in the story! Alpha has NOTHING to do with the LHC other than happening to be in the same lab. These guys need to get the anti-protons down to almost zero velocity so starting with the highest energy machine on the planet would be stupid.
In fact Alpha uses the Anti-proton Decelerator which uses the CERN Proton Synchrotron (PS) which is one of the low energy machines at CERN accelerating protons to only 25 GeV - which is so low in energy that the protons have to be accelerated by another machine, the SPS, before they can even be injected into the LHC for final acceleration!
NASA's page is good, see the last 3 paragraphs under the title "surface of last scattering"
http://map.gsfc.nasa.gov/universe/bb_tests_cmb.html
then could read the whole page from the beginning, good stuff.