Anti-Matter Created By Laser At Livermore

zootropole alerts us to a press release issued today by Lawrence Livermore National Laboratory, announcing the production of 'billions of particles of anti-matter.' "Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear. The anti-matter, also known as positrons, shoots out of the target in a cone-shaped plasma 'jet.' This new ability to create a large number of positrons in a small laboratory opens the door to several fresh avenues of anti-matter research, including an understanding of the physics underlying various astrophysical phenomena such as black holes and gamma ray bursts." The press release doesn't characterize the laser used in this experiment, but it may have been this one.

Comments

Hey!

[Robin47]

Watch where you point that thing!

Re:Hey!

[MarkRose]

Don't lase me, bro!

Holy Mackerel!

[AKAImBatman]

Does anyone know how much energy this takes? They mentioned the previous petawatt laser experiment that was decommissioned, but I didn't see where it mentioend the power required for this experiment. If the laser guess by kdawson is correct, we could be looking at a mere 400 joules per 1E11 positrons. Which (if I'm not mistaken) would be an unheard of efficiency for creating antimatter! (Can someone verify? My brain is fried at the moment.)

What I find interesting is that this level of production is competitive with Fermilab. Even if they ran this twice an hour, they'd handily meet or outstrip Fermilab production.

Even more interesting is the possibility for mass manufacture of antimatter. By using mass-produced gold targets, you could rotate the materials in and out of the machine every few seconds, creating previously unseen amounts of antimatter. Such a process could easily provide materials for an antimatter catalyzed fission drive. Possibly even enough to power new forms of interplanetary propulsion.

Am I the only one who's getting really excited about this? /dreamer

Re:Holy Mackerel!

[FlyByPC]

Even more interesting is the possibility for mass manufacture of antimatter. By using mass-produced gold targets, you could rotate the materials in and out of the machine every few seconds, creating previously unseen amounts of antimatter.

If true, this is the 1940s all over again -- only on a larger scale. A thimbleful of antimatter would make any H-bomb look like a popgun. (...and yeah, I know we're not yet talking about anywhere near that order of magnitude. Yet.) It would certainly help with space exploration -- but we humans can't even be completely trusted with gunpowder and jet airplanes yet. *sigh*

Re:Holy Mackerel!

[Joe The Dragon]

Just use a zpm to power it.

Re:Holy Mackerel!

[AKAImBatman]

Why is everyone so hung up on an energy-positive reaction? Antimatter is the ultimate in fuel for space-propulsion as it produces the highest theoretical amount of energy for the least possible mass. (i.e. 100% conversion - losses to nuetrinos that cannot be captured) This plays well into the rocket formula, giving antimatter drives a specific impulse unattainable with other rocket methodologies. In fact, the far-flung future may see c-ships traveling the stars based on matter-antimatter drives.

What I want verified is not if this process is energy efficient or not. I want to know if this process is several orders of magnitude more efficient than the current Fermilab and CERN processes.

Sure, you could use the antimatter to fuel some other reaction as you suggested, but then again we already have fission reactors which produce net positive energy.

Once again, antimatter catalyzation makes the fuel more efficient for its weight and thus plays well into the rocket formula.

Re:Holy Mackerel!

[AKAImBatman]

If true, this is the 1940s all over again -- only on a larger scale

Not really. We've already done the whole Cold War/Mutually Assured Destruction thing. Our weapons are already far, far larger than we could ever deploy here on Earth. Making them that much bigger only makes them that much more useless. At best, the only real advantage would be that they could be scaled down.

Until we start looking at warfare on an interplanetary or interstellar scale, our existing nukes and possible antimatter warheads are going to sit in their silos and go unused. Or in the case of antimatter bombs, I simply hope they're not built. The idea of a large-scale antimatter warhead being prevented from detonation by mere magnetic fields maintained by the nearest power plant is not an appealing idea. Just disrupt the power infrastructure for long enough and we'll blow ourselves to kingdom come. :-/

Re:Holy Mackerel!

[zippthorne]

60e6*1e3 kcal / c^2= 2.8 kg of antimatter will give any H-bomb look like.. uh.. something that's the same size as an H-bomb. H-bombs have been proposed (and postulated to have been built) that are larger than 60 MT, and a pop-gun typically has only a few Joules, so you'd need many orders of magnitude more than 2 kg of antimatter to make an H-bomb look like a pop-gun. something like.. four times the mass of mount Everest, in antimatter.

Re:Holy Mackerel!

[techno-vampire]

It's even worse than that. During a panel at LACon II, back in '84, Dr. Robert Forward said that according to the best calculations, if you dropped a lump of anti-matter on the floor, it wouldn't vanish in a flash of gamma rays, it would sizzle like a drop of water on a hot griddle. You see, the anti-matter can only interact with its environment and annihilate on its surface, and there's this little thing called the "cube-square law" that says that very little of it is going to be on the surface.

Re:Holy Mackerel!

[AKAImBatman]

Nukes have already been used

Yeah, once. (Twice if you want to be pedantic.) Then never again. The whole point was that the display of force showed that the weapons were too dangerous to use. As long as the various sides have them pointed at each other, no one dares use them.

The only reason why the Cold War was so terrible was that the USA and the USSR were both waiting for the other to attack. Since neither one liked each other much (for both idealogical and practical reasons) the chance that an armed conflict would happen between the two powers was pretty darn high. Except that an armed conflict might precipitate into a nuclear war should either side feel backed into a corner.

Thus the reason why the US didn't win Vietnam. The chance of starting a nuclear war was too great to risk pressing the war to a conclusion. Which raised the (very legitimate) question of why we were even in the conflict to begin with.

Re:Holy Mackerel!

[Ann Coulter]

It should be (60e6 * 1e3 kcal) / (2*c^2) = 1.39659835 since the normal matter that will also be annihilated will contribute to the mass-energy conversion.

Re:Holy Mackerel!

[techno-vampire]

Nuclear devices in the megatons have only been deployed and detonated in a theater of openly declared war twice.

If you're referring to Hiroshima and Nagasaki, you're wrong. Both of those devices were in the kilotons, not megatons.

Re:Holy Mackerel!

[JohnFluxx]

I did the calculations for an earlier post:

If you accelerate at 9.8m/s^2 for half the journey and -9.8m/s^2 for the second half of the journey (so that it's just like earth's gravity) then you would arrive at the planet after:

1.94 arccosh(n/1.94 + 1) years

For n=10.5 light years, this gives 4.9 years.

For other values of distance:
4.3 ly nearest star 3.6 years
27 ly Vega 6.6 years
30,000 ly Center of our galaxy 20 years
2,000,000 ly Andromeda galaxy 28 years

(For distances bigger than about a thousand million light years, the formulas given here is inadequate because the universe is expanding. General Relativity would have to be used to work out those cases.)

So for someone in the rocket, they could arrive at the planet in 4.9 years.

If you had an 100% efficient engine (using anti-matter/matter), the fuel required would be:

d Stopping at: M
4.3 ly Nearest star 38 kg
27 ly Vega 886 kg
30,000 ly Center of our galaxy 955,000 tonnes
2,000,000 ly Andromeda galaxy 4.2 thousand million tonnes

I find it fascinating that within a human lifetime (for the people in the rocket) we could travel to another galaxy.

(I'm a theoretical particle physicist)

Re:Holy Mackerel!

[JohnFluxx]

Time dilation and distance contraction. This are special relativity effects.

For the people on earth, the ship takes 4 million years to travel 4 million light years at close to the speed of light. But for people in the rocket, it can be a very short amount of time.

doh!

[Digitus1337]

Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear.

It's so simple, I wish I'd thought of it!

Lasers

[Chuck Chunder]

Is there anything they can't do?

Re:Lasers

[superdave80]

It's even more amazing when you consider that when lasers were first developed, no one thought they would have much practical use. They were "A solution looking for a problem."
http://www.press.uchicago.edu/Misc/Chicago/284158_townes.html

Now, try to imagine modern technology without lasers...

Hot plasma jets!

[Dutchmaan]

The anti-matter, also known as positrons, shoots out of the target in a cone-shaped plasma 'jet.'

Apparently, it seems I can create anti-matter from eating too much TacoBell.

Science Journalism Critique FAIL

[Anonymous Coward]

Either that, or he/she just isn't a good writer -- that statement implies that all positrons are anti-matter and all anti-matter is positrons. Only the first statement is true.

Nice try, but not true. Your argument would be correct if the statement had read "Anti-matter, also know as positrons...", but it does not. Rather the author says "The antimiater, also known as positrons...".

This sentence only refers to the antimatter created during this experiment. And, near as I can tell, positrons are indeed the only form of antimatter produced in the experiment.

The lesson here - don't post smug messages denouncing someones incorrect grammar when their grammar is in fact correct. Check your facts.

Quick question for anyone with the knowledge

[Hojima]

Does anyone know if this might someday lead to antimatter plants? From a special on discovery, I heard that antimatter has a 100% mass to energy conversion, and uranium/plutonium is very expensive to enrich, so using gold for energy wouldn't be too impractical. This would be very exciting research if it does mean cheap energy at that scale with no pollution.

Re:Quick question for anyone with the knowledge

[nebaz]

No. While antimatter may have a 100% mass to energy conversion, it takes more energy to create it than it gives off.

Re:Quick question for anyone with the knowledge

[CroDragn]

You can't generate a net positive energy source with antimatter. Best you can hope for is to use the antimatter as a form of energy storage (think battery, fuel, etc). Of course, storage problems make it impractical for nearly every use, so don't expect anti-matter cars... ever. Space travel, however, would greatly benefit from a decent means of generating antimatter, since fuel mass trumps most other concerns in that field and anti-matter provides the most thrust/mass of any theoretical substance.

Re:Quick question for anyone with the knowledge

[hvm2hvm]

They created billions of positrons with a high power laser. The antimass(?) of a positron is the mass of an electron or 9.1E-31. Let's round it up and say we have 1E+12 positrons. Combine them with 1E+12 electrons, you get
9.1E-31*2E+12*(3E+8)^2=0.018 J.

Now I'm guessing the laser used is pretty powerful and that it consumes a lot of energy. If we take the specs of the laser linked in the summary, then it used 150J on one pulse which is not the true amount of energy they put into the device (it says it takes 30minutes between pulses at full power). The energy used is thousands or millions of times greater than the energy gained.

Of course, lasers might not be the most energy efficient way of creating antimatter but that doesn't change the fact that if you want to turn m matter into antimatter you will need at least 2*mc^2 energy (at least that's my intuitive guess).

Nuclear devices emit huge amount of energy with relatively small energy inputs because the reaction is selfsustaining, something inside the reaction keeps it alive. What you want is something that destabilizes matter and makes it turn into energy by, say, throwing a special particle at neutrons and/or protons. Turning it into antimatter only to collide it with matter afterwards is just a huge waste of energy.

Re:Quick question for anyone with the knowledge

[ultranova]

You can't generate a net positive energy source with antimatter.

Make hydrogen containers with very thin gold walls - or more likely frozen pellets coated with gold. Bombard the gold with a laser, turning the surface layer into antimatter. Antimatter annihilates with the matter below it and creates an explosion, which heats and compresses the hydrogen, igniting a fusion reaction.

It is, essentially, the equivalent of a fission-initiated fusion, which is proven to work and work well. The difference is that there's no lower bound to the size of an antimatter explosion - even a single electron and positron annihilate - so you can make the explosion be of suitable size for a power plant. And of course annihilation, as the name implies, doesn't leave behind radioactive materials, just gamma rays.

Besides, Laser Antimatter Fusion is pretty much the epitome of cool ;).

Re:Quick question for anyone with the knowledge

[sdpuppy]

Yes, this experiment accomplished - converting energy into antimatter

The point is having the ability to produce lots of these particles in a directed manner, capture and store them for further study.

Previously the main source for antimatter was certain types of radioactive decay and nuclear reactions.

(example: if you go to the hospital for PET imaging - they inject you with radioactive material that decays by emitting anti-electrons = positrons)

If you want something that could potentially produce energy, this is not it - although in studying the process and the particles we might eventually learn how to produce antimatter more efficiently (to store energy) or perhaps even with net gain by inducing some sort of nuclear reaction.

Re:Where's the boom?

[compro01]

You are fantastically overestimating how much they made. 100 billion particles seems like a lot, but it's actually only about 9.1x10^-17 grams (91 attograms). You could likely be physically standing right in front of the thing, in the middle of the spray of particles, and not notice anything.