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NC State Creates Most Powerful Positron Beam Ever
Posted by
ScuttleMonkey
on Mon Oct 22, 2007 05:19 PM
from the there-are-four-lights dept.
from the there-are-four-lights dept.
eldavojohn writes "A fairly large breakthrough took place earlier this month with the most powerful man-made antimatter electron beam ever being created at North Carolina State University. Professor Hawari who worked on the project explains its benefits: 'The idea here is that if we create this intense beam of antimatter electrons — the complete opposite of the electron, basically — we can then use them in investigating and understanding the new types of materials being used in many applications.'"
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Obligatry (Score:5, Funny)
I have a radical idea... (Score:3, Funny)
Re:I have a radical idea... (Score:5, Funny)
Parent
Re: (Score:3, Interesting)
Re: (Score:3, Funny)
And anyway, as a Trekkie, I can tell you that you're completely wrong; they use "anti-matter" drives. According to Star Trek, anti-matter is just as "bad" as gasoline: if something bad happens they both blow up.
Re: (Score:3, Informative)
However antimatter does not to our knowlage occour in significant quantities naturally and it isn't feasible to make enough of it to be dangerous (we have to make it from energy and I don't think the process is very efficiant).
Re:Obligatry (Score:5, Funny)
Also, when do we get the stories of the police using weaponised versions of the antimatter gun on students?
"Don't positron me bro!"
Parent
Re:Obligatry (Score:5, Funny)
Do the students emit photons when they relax?
Parent
Re: (Score:3, Funny)
Opposite of electrons... (Score:4, Funny)
Re: (Score:3, Funny)
Actually, it blocks out all positive thinking. Sheesh! Some scientist you are...
Omitted text from the article (Score:5, Funny)
He added: " We are not quite sure how long it will take to miniaturize the technology for shark mounted applications, but we expect this to be investigated thoroughly in the future"
Little useful info in TFA (Score:2, Insightful)
Apparently outdoing some undisclosed reactor in Munich is about all they say.
Apparently in 1985 you couldn't walk into a store and buy plutonium but perhaps in 2015 you can buy antimatter.
Re: (Score:3, Interesting)
Jesus Christ in a Chicken Basket (Score:3, Insightful)
You know, when you've read as many science fiction books as I have, this shit is a liiiitle creepy.
Re:Jesus Christ in a Chicken Basket (Score:5, Informative)
Why? These are usually research reactors, from what I understand. They're not meant to power cities; they're not meant to run at a profit. They're meant to generate some types of isotopes for nuclear medicine students, and to give the nuclear engineers something to do.
I've read a lot of science facts, and that's why this shit doesn't feel that creepy at all. I don't mean to single you out, of course, and there are plenty of valid security and OSHA-like concerns at pretty much any nuclear facility; the public's allergy to anything remotely involving the word "radiation," however, is something that could stand a lot of improvment. The dangers of nuclear science are more to do with mismanagement and a lazy operating culture--which are thankfully not fundamental physical issues but rather human ones that can potentially be fixed.
And, frankly, I'd rather the public learn about nuclear science from scientists rather than science fiction authors.
Parent
Re: (Score:3, Informative)
You know, when you've read as many science fiction books as I have, this shit is a liiiitle creepy.
This isn't a little creepy. Idiocracy [netflix.com] is a bit creepy. Manna [marshallbrain.com] is a bit creepy. And this Wired story [wired.com]is down right scary and creepy. If we continue down this path, then we are well on our way to being a nation of idiots.
Re:Jesus Christ in a Chicken Basket (Score:4, Informative)
Parent
Re: (Score:2)
Re:Jesus Christ in a Chicken Basket (Score:4, Informative)
Did they also mention that these reactors have a very low power output and that you couldn't cause a meltdown even if you tried? Even for a dirty weapon the material in these reactors would be rather useless. You can find more dangerous chemicals in your local paint shop.
Having said that, I think we should ban the nuclear family on health and safety grounds. IT'S NUCLEAR! THINK OF THE CHIDLREN!
Parent
Re:Jesus Christ in a Chicken Basket (Score:4, Funny)
Parent
Re:Jesus Christ in a Chicken Basket (Score:5, Informative)
Nuclear reactors generally pose two threats. The first is that they will get out of control. That can't happen at NC State. By the time the water gets hotter than bathwater, alarms would be going off. The reactor isn't allowed to get at all close to boiling.
The other risk comes from the radioactive substances being stolen. Ignoring the fact that the stuff in the reactor is the least accessible stuff in the building, you would need lethal weapons and scuba gear to get significant quantities out of the reactor room. Getting the stuff off campus would be even harder.
There is a much bigger risk of somebody raiding the chemistry labs for chemical weapons materials.
Parent
Re: (Score:3, Informative)
1.) The fuel rods are something you can just "remove." This action poses some purely physical difficulties- they're meters underwater, bathed in a deadly neutron flux, and have to be removed by tools taking a lot of time.
2.) Monitors at access points would detect something being removed and sound alarms.
3.) You don't really get to be alone with the reactor for any period of time worth mentioning.
4.) Fuel rods aren't the attractive t
Re: (Score:3)
Not Quite (Score:5, Interesting)
Parent
Re: (Score:3, Insightful)
Most newsmen (judging by their use of the term "many" in place of actual integers - even very small ones - in most of their stories.
Either that or they think their audience can't understand numbers greater than three or so.
Really! In "most" of their stories they use the term "many" in place of apparently uncounted small numbers. Wonders never cease.
positron rifle from Evangelion? (Score:2)
I for one . . . (Score:3, Funny)
In seemingly unrelated news, Duke University ceases to exist, somehow evaporated by a wave of unknown positron emission energy. But little seem to care, since Duke sucks anyways!
Re: (Score:2, Informative)
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Re:I for one . . . (Score:5, Informative)
Parent
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"Several UNC students carrying buckets of carolina blue paint have been missing since the big UNC win last night. In seemingly unrelated news, this morning NCSU campus police found several strange-looking piles of ash by the Free Expression Tunnel."
Don't cross the beams! (Score:3, Interesting)
Re:Don't cross the beams! (Score:5, Informative)
Kinda. It's more like a gamma-ray (and neutrino) light source. The electron-positron annihilation releases a tad over a MeV mainly as two photons that fly off in opposite directions - plus a neutrino, so the photons are somewhat under half the energy each.
Think of it as an x-ray tube - without the vacuum tube - but with the power supply, instead of being in the kilovolt range, cranked up to whatever the beam voltage is plus an extra half-million volts or so.
Also, if you have a target you don't really need the electron beam. Just ground it well enough that it doesn't accumulate enough positive voltage to deflect the positron beam to somewhere else.
Parent
Re: (Score:3, Interesting)
Naw. It would have to hit something to glow. And it wouldn't be much of a beam with an acceleration voltage in the single-digit volts needed to produce visible light when the electrons slam into something.
As for trying to make a middle-of-the-air display by intersecting electron and positron beams: While half-MeV gamma-ray photons count as "light" they don't count as "visible light" (unless the light is really bright and
Use it on drug resistant bacteria (Score:3, Funny)
How is the beam manipulated? (Score:3, Insightful)
Re: (Score:3, Informative)
Like an electron beam - with electric and/or magnetic fields. (But because the particles are positive you have to use the reverse of the fields you'd use on electrons.)
doesn't it cause an explosion if it touches normal particles?
It causes a spot of gamma-ray (and neutrino) "light" emission. Kinda like an x-ray tube with a half-million volts between the electrodes (minus the vacuum bottle).
can it be used as a weapon?
If you have a BIG truck to carry the swimming-pool reactor arou
Re:How is the beam manipulated? (Score:5, Informative)
http://www2.slac.stanford.edu/vvc/detectors/sld.html [stanford.edu]
In the diagram shown in the link above, look for the e- and e+ labels. Those represent the electron (e-) and positron (e+) beams entering the SLD detector from opposite sides. In the center of the SLD detector is a small cylindrical piece called a Vertex Detector. The center of the vertex detector (a silicon CCD device about the size of a soft drink can with several million pixels in three concentric layers) is where SLAC's electrons actually collided with positrons. The parts of the detector around the Vertex detector are like the layers of an onion. Each layer gathers a different kind of data about the collisions that took place inside the vertex detector at the interaction point. There are a lot of very sophisticated electronics in the layers of all particle detectors, but all of the electronics have one purpose, to gather information about the decay fragments coming from the electron/positron collisions so the events that took place during and immediately after the collision can be reconstructed and analyzed with very sophisticated computers.
Beginning in 1998, SLAC began an experiment called the asymmetric B-meson factory, or "B Factory" for short. In the B Factory, the electron beams run at a little over 9 GeV beam energy, while the positron beams run at only about 3 GeV. Both colliding beams run at very high currents, on the order of two amperes in the electron storage ring, and three amperes in the positron storage ring. The collision of these two high current beams produces millions of B mesons, each with a residual momentum (due to the asymmetric beam energies) that makes it possible for the particle physicists to study more effectively how those B mesons decayed.
Here is a link to more information about "Storage Rings" and their electromagnets:
http://en.wikipedia.org/wiki/Storage_ring [wikipedia.org]
And here are links to three of SLAC's web pages, where you can learn more about colliding beam physics. BaBar is name of the particle detector used to study their decaying B Mesons, and PEP-II is the storage ring collider used to make those B Mesons.
The PEP-II storage ring collider is at: http://www.slac.stanford.edu/grp/ad/ADPEPII/ADPEPII.html [stanford.edu]
The BaBar detector is at: http://www-public.slac.stanford.edu/babar/ [stanford.edu]
And SLAC's main web page (the first web page in t
Parent
Re: (Score:3)
Brilliant and informative post (used up all my mod points yesterday -- bugger!)
One observation however deserves expansion, I believe. The object ...The center of the vertex detector (a silicon CCD device about the size of a soft drink can reminds me of how the original cloud chamber reaction detector was inspired by a glass of beer, or rather the cavitation of bubbles within the glass of beer (not that beer can't be inspring on
Re: (Score:3, Interesting)
I used to work at SLAC, and I got to know something about how the whole machine worked and what we (as a member of the team who made it work) were doing. You are 100% correct about beer and bubble chambers. At one time SLAC had a huge bubble chamber filled with liquid hydrogen (as I recall, I could be wrong). They also had a huge cloud chamber, and even a very large spark chamber, and giant solenoid magnets around those chambers, to make charged particles leave curved trac
Antimatter electron? (Score:2)
Re: (Score:3, Funny)
Yes, positrons are considered anti-matter. But you can call it what you want in your own Jeffries tubes.
She can't take much more of this! (Score:5, Funny)
uh o (Score:3, Funny)
-sigh- (Score:2)
Insert joke here about Dirty Hawari with the Most Powerful Postitron Beam in the world, and can blow a grad student's head clean off...
I know there's a good joke here, but it's not coming to me. -sigh- Some days you have it, some days you don't. :)
I'm not impressed (Score:4, Funny)
Useless without... (Score:3, Interesting)
Re:Ghostbusters!! (Score:5, Informative)
There are probably a whole bunch of other experiments that positrons would be great for performing, but intense positron sources are not readily available. The development of more intense positron sources will certainly be welcomed by the scientific community, as it may allow previously unimagined types of measurements.
Parent
Re: (Score:3, Funny)