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

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!

[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!

[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: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...

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.