3mm Inexpensive Chip Revolutionizes Electron Accelerators 113
AaronW writes "Scientists and engineers at the US DOE SLAC National Accelerator Laboratory and Stanford University have developed an advanced accelerator technology smaller than a grain of rice. It is currently accelerating electrons at 300 million volts per meter with a goal of achieving 1 billion EV per meter. It could do in 100 feet what the SLAC linear accelerator does in two miles and could achieve a million more electron pulses per second. This could lead to more compact accelerators and X-ray devices."
Re:Or, another option (Score:5, Funny)
Re:Or, another option (Score:4, Informative)
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Re:Or, another option (Score:5, Interesting)
Those units don't even have the same dimension, how do you propose to compare them?
1 Watt is a Joule per second. An eV is 1.6*10^-16 Joule. Now according to the theory of relativity, space and time are just different dimensions of the space time, therefore space units and time units are related. The factor is the light speed, 3*10^8 m/s, that is, a second is 3*10^8 meters, or a meter is 1/(3*10^8) seconds
Therefore 1 eV per meter is 1.6*10^-16 Joule * 3*10^8/second, or 4.8*10^-8 Joule/second. Now a Watt is 1 Joule/second, therefore 1 eV/m is 4.8*10^-8 Watt.
On the other hand, 1.21 Gigawatt are 1.21*10^9 Watt. Which is a factor of about 2.5*10^16. So still quite a way to go for time travel.
SCNR ;-)
And in order to not confuse anyone: the calculation above is of course meaningless because even though you can make the *units* the same using relativity, the *quantities* are still completely different; just like the torsional moment has the same unit as energy, but certainly is not the same as energy.
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Not as meaningless as you think: http://en.wikipedia.org/wiki/Electronvolt#Distance [wikipedia.org]
Re:Or, another option (Score:5, Funny)
Those units don't even have the same dimension, how do you propose to compare them?
Very carefully?
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you misspelled "jigga"
Re: Or, another option (Score:2)
Nope. People just mis-pronounce giga.
Look it up, we should be pronouncing gigabyte as "jiggabyte".
Good news, everyone! (Score:2)
It's about time we had some more nuclear monst^H^H^H^H^H boy scouts! They used to call me mad, you know. And why? Because I dared to dream of my own race of atomic monsters, atomic supermen with octagonal shaped bodies that suck blood...
Re:Neutron generator (Score:4, Funny)
Give me an efficient source of neutron flux and I can stop collecting smoke detectors. I'm kidding obviously, but if this is cheaper than collecting radium watch hands we may soon have more "Nuclear boy scouts" on our hands.
On the plus side, not all neutron generators are polite enough to stop generating when you cut the power, so it might be an improvement.
More like Gamma-ray devices (Score:2, Interesting)
Unless you can somehow turn down the volume of the device, 300 Mev photons are high-power gamma rays, not x-rays. BTW unlike regular x-rays, at gamma energy levels you can actually activate matter, I.E. turn it radioactive.
Re:More like Gamma-ray devices (Score:5, Informative)
"300 Mev photons are high-power gamma rays, not x-rays."
No, an accelerator of 300 MeV per meter over 3 mm gives you 1 MeV, or less if the actual field is over less than the chip size. Tuning down from there will easily get you into the x ray domain.
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Ahh didn't see it was 300 Mev *per meter*. Small detail, thanks!
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Ahh didn't see it was 300 Mev *per meter*. Small detail, thanks!
This masterful demonstration of The Save reminds me of the way a cat lands on its feet no matter how it is thro^H^H^H^H^H^H^Hfalls.
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*facepalm
Neutron radiation != EM radiation (photons) != Beta radiation (electrons)
Neutron radiation messes with nuclei and can make matter radioactive. EM radiation and beta radiation generally do not. Furthermore, you can't accelerate photons (x-rays and gamma rays) since they all travel at c. You can't accelerate neutrons because the only forces that act on them aren't macroscopically accessible. This is an electron accelerator.
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Fair enough, just two questions:
1) An electron hitting an atom will produce photons with the same energy via the Bremsstrahlung effect. As electrons will hit atoms sometimes, 300 MeV electrons means you will have 300 MeV photons, right?
2) How much energy a photon needs to transmute an atom? I believe it's lower than 300 MeV (but as a commenter said, it's 300 MeV *per meter* so really you need a lot of those devices chained together for them to become dangerous, I guess)
Re:More like Gamma-ray devices (Score:5, Informative)
1) You'll probably get some photons out of the deal but they won't all be 300MeV. There are lots of places to put energy (this is what makes particle physics hard) and photons are only one of those places. See the light-matter interaction box on the "Photoelectric_effect" wiki page. At 1MeV, even pair production becomes viable.
2) Photons don't transmute atoms (search for "photonuclear reactions" for the exceptions). Neither do electrons (look up "Electron_capture" for the exception, but it generally only happens with electrons already bound to the nucleus rather than ones flying around). Neutrons transmute elements because they can ignore the Coulomb barrier. Irradiating, say, rubber tubing with gamma radiation won't make it radioactive (it'll probably make some radicals and mess with the chemistry, but nothing nuclear). Neutron radiation is a totally different story.
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The SLAC isn't a spallation radiation instrument. It produces xrays by coherent synchrotron radiation: as the electron beam passes through the end-stage undulators, the electrons are undulated at a fixed wavelength by a series of alternating undulator magnets, the wavelength of which is shorter (higher energy) than that of the spacing of the undulators because the electrons "see" the undulators as closer together due to time dilation, the electrons, still carrying over 99% of the bunch energy are then diver
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My first thought when reading this was that it would an interesting exercise to make a free electron laser using this electron source.
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photons over 1GeV can indeed transmute nucliei.
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1. This accelerator, like SLAC (in it's current configuration), accelerates electrons, and the accelerated electrons are undulated (wiggled) in a vacuum to produce xrays (photons), then the electron beam is deflected off-line into a beam absorber, nearly all of the beam energy at SLAC is discarded, rather than reaching the experimental target. This is unlike most xray sources which generate xrays by spallation (collision with atoms), as the energy (wavelength) of the photons has the same bandwidth as the pa
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Shouldn't the neutron be paired with something composed by its anti-quarks? If so, you'd need a photon with about 2TeV, what needs an accelerator at the "huge" end, not "lab-sized".
Also, that's not my area so I may be completely wrong, but it looks quite unlikely that you'll generate exactly 6 quarks with different color and barionic numbers, so that they can organize as a neutron.
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Also, that's not my area so I may be completely wrong, but it looks quite unlikely that you'll generate exactly 6 quarks with different color and barionic numbers, so that they can organize as a neutron.
That would depend on if you are watching(or not)?
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There are photoneutrons. If I recall correctly they are typically produced by high energy photons hitting deuterium. The neutron produced can go an activate material around it. For a nuclear reactor that has shut down, photoneutrons are the dominant form of source neutrons produced for a little while (the gammas come from beta decay which drops off over time).
Re:More like Gamma-ray devices (Score:5, Informative)
The modern classification of x-ray vs. gamma-ray is based on the source of the emission (electron vs. nucleus), not the wavelength. http://wiki.answers.com/Q/What_is_the_difference_between_gamma_rays_and_X-rays [answers.com]
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Astronomers may call it gamma radiation because they don't know the source. It's true that most natural higher energy radiation is gamma while lower is x-ray, but there is overlap between the two and artificial or unusual sources (like particle accelerators) can produce very high energy x-rays, or very low energy gamma rays.
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Wikipedia [wikipedia.org] agrees that the distinction is usually made on source as opposed to energy, and points out that how it's done depends on the field of study (for example, in astronomy it's made based on energy since the source may be uncertain). Personally I think it should always be done based on energy alone and that these different fields should standardize on that.
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It is standard - it's based on the source. And that's a useful distinction, far more so than the energy.
You said it yourself - astronomers may differentiate based on energy simply because they don't know the source, so they have to assume it. If they know the source, or have a good reason to think it's something in particular, they use the standard terminology.
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http://www.youtube.com/watch?v=p0u8rI0JvaM [youtube.com]
The only part of the above link that matters.
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Ignoring the rest of the URL, which clearly does not point to a .dmg file, just about everyone can safely "click" links that end in .dmg as a dramatic majority of users do not own a Mac.
Further, why would the few Macs users, having downloaded such a file, blindly execute its contents?
Really, the only people who could possibly be in danger from such a link would necessarily be both a Mac users and unimaginably incompetent.
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Riiiiiight, because anyone in their right mind is gonna click a random link ending in .dmg... Aka, a Mac disk image file, commonly used for distributing software.
Hey, if you think that it's diseased, don't mount it. Did you skip sex ed or something?
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Have you really never dissected a google url before??? This person clearly searched for "positron collider ghostbusters" and pasted the YouTube link that came up in the search results.
Re:so we wasted a shit load of money on colliders? (Score:5, Insightful)
Computers are commercially funded (Score:1)
We clearly shouldn't have wasted all the money on mechanical and tube computers and just waited until we got i7s.
We didn't. Early computers were funded from commercial sources not taxation, and they had practical applications right from the start.
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We didn't. Early computers were funded from commercial sources not taxation, and they had practical applications right from the start.
ENIAC was arguably the first general purpose electronic computer, and it was built for the US military (a wing of their government). Zuse's Z3 was arguably the first general purpose electric computer, and it was built for the German Air Ministry (a wing of their government). Of course, these devices are practical applications representing the culmination of centuries of prior basic research. The basics of electrical and electronic science was performed in the seventeenth and eighteenth centuries, largely
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ENIAC was arguably the first general purpose electronic computer, and it was built for the US military (a wing of their government).
You are right, there was a lot of government funding at the start of the computing era. But most of the work that took us from the Antikythera Mechanism to the modern 28nm processor was privately funded.
My point is that you can't compare the development of modern computers, which was mostly a commercial engineering process, with the advancement of particle physics, which is mostly a tax-funded scientific process. The money that might have been "wasted" on colliders is a different kind of money from that us
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At this rate, in 50 years we'll be carrying them around and debating if personal linear-accelerator-guns are covered under the 2nd amendment.
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Well, the path of least resistance to ground is probably going to be the person holding the pocket lightning gun which will severely limit the number of people who would be willing to pull the trigger.
It would be an awesome way to commit suicide, however, and I'm sure all the bystanders would be suitably impressed by the light show if you did it at night.
And my captcha for this post is 'physics'... how appropriate.
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At this rate, in 50 years we'll be carrying them around and debating if personal linear-accelerator-guns are covered under the 2nd amendment.
"The only way to stop a bad guy with a linear accelerator is a good guy with a linear accelerator. Or, um, a layer of lead, DU, tungsten, or some other fairly dense material, of appropriate thickness. Wait, did I mention lead? Where was I?"
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The inverse square law provides the best shielding.
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Or a dense material like... air. A sheet of paper works quite well too.
Re:so we wasted a shit load of money on colliders? (Score:4, Interesting)
These new devices only accelerate electrons. For high energy physics research other particles need to be accelerated and collided, e,g, hadrons (hence the name Large Hadron Collider) It's unclear if the same tech can be used for other particles. Rubbish TFA.
Re:so we wasted a shit load of money on colliders? (Score:5, Informative)
If you read the article, you'll realize that there is a separate laser accelerator necessary BEFORE this chip, and then a second high-power IR laser necessary to drive the chip.
More-or-less, they've increased the efficiency of laser-based electron acceleration. Good on them, but the solution isn't, as the summary suggests by omission, just a small chip alone and nothing else.
More importantly for the parent (I know, I know, don't feed the trolls), the presented accelerator only accelerates electrons, and is intended as a gamma and x-ray source. That's very different from accelerating electrons and positrons to nearly the speed of light, or protons, or atomic nuclei, etc. To do high-energy physics, you need big, big accelerators. The device to accelerate a single subatomic particle to levels where it carries as much energy as a brick dropped on your foot, isn't going to be a crystal a few millimeters on a side.
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Not quite. While one or a few of these chips might make a nice small source of x-rays or electron beams they are certainly interested in putting a bunch of them together to make high energy physics linear electron accelerators (thus the comparison to SLAC). It would still be big, but since these things are more efficient than the microwave acceleration normal linear accelerators use, you could build a smaller one that achieved the same energy. Or a same size or bigger one that achieved higher energies.
Th
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Actually yes. Luis Alvarez, a Nobel Prize winning experimentalist argued extensively that large grants make experimentalists lazy. He joked that Michelson-Morley today would be done by launching antipodal satellites with expensive laser alignment hardware at the very low cost of $300 million.
Something very important... (Score:2)
This could lead to more compact accelerators and X-ray devices.
Just don't cross the streams. [wikipedia.org] It would be bad.
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I'm fuzzy on the whole good/bad thing. What do you mean, "bad"?
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I'm fuzzy on the whole good/bad thing. What do you mean, "bad"?
Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light.
[Or so I've heard.]
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Right. That's bad. Okay. All right. Important safety tip. Thanks fahrbot-bot
Foreseeable effects? (Score:2)
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developed an advanced accelerator technology smaller than a grain of rice
You can get rice that cooks itself and you too! In soviet America , rice cooks you!
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It might enable radars of similar size, cheap enough to mount in every air vent in your house and able to direct the chilled air at people; combined with similarly miniaturized heat sensors, you'll find yourself cooling off or warming up much more quickly after coming inside.
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The main problem is that electrons of such high energy produce X-rays when they smash into something (or are accelerated), and X-rays are dangerous. One could imagine home X-ray scanners, if we could get through the regulatory clusterfuck. Maybe one could make a weapon, if the beam intesity was ramped up by placing many of htese in parallel.
Particle physicists are planning the next thing after LHC, and it's a linear electron-positron collider. The device only claims to accelerate electrons to 1 GeV in the b
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Is this because the LHC is wasting a lot of power with synchrotron radiation? The LHC is already running at about 3.5TeV/beam giving 7TeV collisions. With the upgrade, they should be able to manage 7TeV/beam.
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Proton and larger particle colliders don't really suffer from synchrotron radiation because the particles are so massive. Electrons are very light so they have to be travelling much faster to have the same energy, thus synchrotron radiation becomes a problem.
Physicists want an electron collider because electrons are fundamental particles. When you smash two of them together (or an electron and a positron) you get a nice clean collision. Protons are composite particles and what you get depends on how the
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That's 1 GeV per metre.
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yeah, it's 1/3 the size of a 9mm bullet.
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this is for cheap proton therapy (Score:1)
The US govt is interested in getting cheap proton therapy machines. Instead of cutting a human open with an expensive surgeon to remove a tumor, the computer controlled proton beam can blast through the skin, and strike the tumor. So yes, this is going to get lots of govt funding. Gains in particle accelerators are merely incidental.
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Proton? But this is an electron accellerator. You could use it to feed a proton accelerator, I suppose....but it wouldn't be simple.
Better to build something analogous and feed it with hydrogen ions. Also note that it requires a preheater stage, and that protons don't have synchroton radiation. So anything analogous is going to be QUITE difficult. (OTOH, protons don't need a linear accelerator, they can use rings.)
Actually, I think nothing even analogous would work for protons. And even doing it with
weapons (Score:3)
LHC@Home (Score:2, Funny)
Why spend 8 billion Euro on something that will be in every kid's room in 5 years? I fully expect "My First Large Hadron Collider" from Fisher Price in a few years so that kids can make their own micro-singularities and find out how meaningless the "God Particle" actually is for themselves.
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Because unless you spend 8 billion on it the first time it never gets to be a children's toy. That 8 billion is the initial investment in these things being commonplace enough to use as cat toys. (If you for some reason want to irradiate kitty's bones, I guess....)
Antimatter factories (Score:2)
If these cold be produced in large quantities and were cheap enough, I wonder how well we could progress in the creation of antimatter. If we could do so, and could improve the penning trap so that the antimatter could be kept for a long time, then many problems with space travel would be solved.
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Take a look at how rocket weight decreases with the energy density of the fuel*, and then read your post again.
* No link. Sorry, but I won't go out of my way to digg one for a random A/C. Try googling something like "rocket equation", and reading the relevant Wikipedia articles. You'll find it if you bother searching.
Channelling is not a new idea (Score:2)
I read a PhD dissertation and was instructed by a professor working on the idea of using chanelling in crystal material to accelerate particles. What was not included then was the addition of lasers. That was the mid 1980s.
First step towards a functioning phaser? (Score:2)
Won't scale (Score:4, Insightful)
At least, it won't scale in the way the article suggests.
It's possible that the tech involved might make for a more efficient acceleration mechanism than the current superconducting electromagnets, but I sincerely doubt it will lead to significantly smaller accelerators: accelerators are large not because it isn't possible to accelerate the electrons in a shorter distance, but because it's extremely inefficient to do so.
Large accelerators are limited by the fact that rapid accelerations of charged particles cause lots of radiation to be emitted. The amount of radiation emitted increases dramatically as the particles approach the speed of light, making it harder and harder to push the particles faster (or even just to keep them going at speed in a ring for circular accelerators). Even if this mechanism of electron acceleration is a hundred-fold more efficient energetically than the SLAC accelerator, it still couldn't accelerate electrons to SLAC speeds in 100 feet, because it would need vastly higher acceleration and that higher acceleration would lead to lots of radiation, limiting the pace of acceleration. Personally, I doubt it's 100 times more efficient. I bet most of that efficiency difference comes from this small device not operating on electrons moving anywhere near the speed of light.
OT: redirect to MoboMarket.apk on first link (Score:1)