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But can you (Score:5, Funny)
Re:But can you (Score:4, Funny)
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NOPE PETA WON'T DO IT (Score:2, Funny)
Re:NOPE PETA WON'T DO IT (Score:5, Funny)
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Re:But can you (Score:5, Funny)
Lawyers?
Sorry.. too easy
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of course you can! (Score:2)
better yet... (Score:3, Funny)
It won't be real genius.. (Score:3, Funny)
What would Chris Knight say? (Score:5, Funny)
The Building Size (Score:2, Redundant)
Ok then I actually read the article and saw that they were i
Re:The Building Size (Score:2)
Daniel
OH come on! (Score:2, Informative)
National Ignition Facility, Livermore (Score:5, Informative)
Here's a site that explains how it works: http://www.llnl.gov/nif/nifworks/index.html
The article does mention NIF, but only at the bottom, briefly. It is not to be overlooked. I've been through the facility -- it's absolutely massive. Full of wondrously expensive and very shiny toys.
Close to me (Score:5, Informative)
Re:Close to me (Score:3, Funny)
An offer you can't refuse... (Score:2, Funny)
"So, you see, the citizens have some concerns about the facility, and..."
(A switch is flipped, a quiet whirring is heard.)
"Umm... approval granted."
Watchout! (Score:5, Funny)
What about.. (Score:2, Interesting)
Re:What about.. (Score:2)
maybe. but then again, the article (if you read it) talks only about how its to be used for nuclear fusion research, an interesting topic on its own.
i was pleasantly surprised that the poster talked about real genius and didnt snipe at the missile defense system, but alas of course it was only a matter of time before people would troll about it.
Time to count... (Score:4, Funny)
Re:Time to count... (Score:3, Funny)
If only... (Score:2, Insightful)
[/sarcasm]
I hope all the sheep that always claim that the US only spends money on DoD stuff figure out that the government (DoE here) does spend money on things other than to kill folks. And its a frick'en laser, and it isn't meant to kill people. Amazing.
Otherwise pretty cool.
Granted the otherside of slashdot that complains about anything with nuclear in it are
Re:If only... (Score:2)
Read the article,
The primary source of funding for the facility there is nuclear weapons stewardship - ie: keeping the US nuclear weapons stockpile warmed up and ready top go.
Hmmm, yep, that would be 'Dud Stuff' and aimed at 'killing people' I would have thought.
Not that they don't do a lot of great research in to other areas, but lets not fool ourselves here.
Re:If only... (Score:2)
CHA (Score:5, Funny)
To carve your name in the MOON!
Why this is needed... (Score:5, Interesting)
For H-bombs, the idea is to use a fisson bomb to kick-start the whole thing.
Now they are trying to build fusion reactors, and obviously using fission power is not that popular (the whole point is to get rid of the problems of fission).
Using extremely powerful and focused lasers seems to be the best idea as yet. This is only needed to start the reaction, once it has started it is kept alive by its own power and a supply of hydrogen.
Tor
Re:Why this is needed... (Score:5, Informative)
It would also be wholly impractical in this case.
What is required, as you say, is to raise the hydrogen to a suitably high temperature and pressure. The laser is used not only to increase the temperature of your target material, but also the pressure (the sudden increase in temperature causes the surface to ablate, which causes an increase in pressure on the remainder of the target). To achieve the same effect using a fission reaction, you would essentially have to create an explosion, which would be *far* harder to do safely. You're likely to just destory the reactor, as only a small fraction of the total output energy of the explosion could actually be directed at the target.
In an H-bomb, of course, the more destructive the reaction the better.
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almost (Score:2)
but in real genius it was only a 5-meg-watt laser. what's this? petawatts? is that like a billion times more powerful than meg?
Petawatts? (Score:2)
Please tell me they are not PETAwatts. PETA is soooo gorram annoying [mentallyincontinent.com].
Already the most powerful UV laser at UR (Score:2)
Re:Already the most powerful UV laser at UR (Score:5, Informative)
First you must make a distinction between most powerful(energy/time) laser and most energetic(energy per pulse) laser, this is a distinction not made in the article. The Omega laser is currently the most energetic ultraviolet(frequency tripled Neodymium:Glass) laser in the world now at ~25 Kilojoules per pulse, very soon to be eclipsed by the preliminary first light of the National Ignition Facility. However each "shot" on the system, as they are called, is only a couple hundred picoseconds to a couple nanoseconds long (depending on the shot pulse shape) making it's peak power around a maximum of about 60 Terawatts. This is not the most powerful laser in the world. The Rutherford Appelton [rl.ac.uk] laboratory in England has a "Petawatt" system they just commissioned which is capable of at least hundreds of Terawatts of power albeit only with a couple hundred joules of energy per shot.
It is interesting to note that the mechanism the Petawatt upgrade at the LLE will use to achieve it's million billion watts of power in a pulse time of a few picoseconds to hundreds of femtoseconds is called Optical Parametric Chirped Pulse Amplification(OPCPA) and was invented right at THE UofR in the late 1980's!! Chirped Pulse Amplification [utoronto.ca] lasers are the only means to get to petawatt intensities and they are interesting because they are the first technology to allow nuclear reactions to be directly caused [llnl.gov] by intense light radiation(ie. no implosion/ heating stage as in ICF). This is really interesting because in addition to the spark plug type inertial confinement fusion catalyzing experiments that are planned, the intensity fluences allowed by petawatt lasers approaches (possibly >10^21 watts/sq. inch) what is necessary to do an experiment called "sparking the vacuum" whereby enough energy is placed in a small enough volume of space in a short enough period of time to cause a spontaneous transformation of energy directly into particles(via E=Mc^2 [princeton.edu]). Neat eh?
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Re:Already the most powerful UV laser at UR (Score:4, Funny)
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In case of Slashdotting (Score:5, Funny)
By Matthew Daneman
Democrat and Chronicle
(May 9, 2003) -- One burst from the University of Rochester's Omega laser heats up its target to 100 million degrees Celsius in a quest to duplicate the power of the sun.
But the world's most powerful fusion research laser is about to get a lot more powerful.
Construction could start as soon as early July on a $70 million addition of a pair of petawatt lasers to UR's Laboratory for Laser Energetics Omega facility on East River Road.
The incredibly powerful petawatt would be the most destructive device in existence, capable of vaporizing an entire planet.
Researchers have a broad array of plans for the petawatt, including using bursts from it to disintegrate major landmarks.
Nuclear fusion is what powers stars, including the sun, and is the principle behind hydrogen bombs. Scientists have been trying for decades to replicate and control fusion for use as a cheap, pollution-free power source.
"They mocked my research!" said lab director Robert McCrory. "But I'll show them
UR is planning for an 82,000-square-foot addition to the back of the laser lab. The town of Brighton Planning Board is having a special meeting at 5:15 p.m. May 19 at the laser lab. The meeting will include a tour for board members and neighboring residents and a demand for cash payments to stave off their imminent destruction.
UR estimates the lab could be fully operational in about four years. When Rebel forces attempt to destroy the shield generators protecting the installation, UR will reveal that it is already fully operational.
The U.S. Department of Energy has put up $13 million so far for the expansion plans, and UR expects to see $37 million more over the next few years. The university is putting $20 million of its own into the construction.
A petawatt laser could generate a pulse of up to a million billion watts of power, several hundred times more powerful than the Omega, and would enable the lab to hold the entire world hostage, said Steven Loucks, engineering director for the laser lab.
"This will be the most intense laser ever built," said Craig Sangster, a senior scientist at the laser lab.
With the petawatt, UR would leap into the emerging and promising field of "fast ignition" fusion. Hypothetically, a burst from the petawatt would serve as the metaphorical spark plug, igniting a fuel source and setting off a fusion reaction, destroying an entire planet. Researchers also foresee using the petawatt bursts to "see" into the plasma generated when the Omega laser array is fired at unsuspecting tourists, "which we'd love to do now, but we can't," Sangster said.
And the petawatt will help in one of the lab's primary jobs -- "stockpile stewardship" of the nation's nuclear weapon arsenal, Loucks said. The vast majority of the lab's $49 million annual operating budget comes from the Energy Department, which pays for study of death rays now that the nation no longer does nuclear testing.
The laser lab upgrade will add no more than a handful of jobs to the facility, which employs close to 250 people in stupid black helmets with wheels on them. But the petawatt will help ensure that federal money continues to flow to Rochester, McCrory said.
Added Lousch: "Do not be too proud of this technological terror you have constructed, for the ability to destroy a planet is insignificant next to the power of the force."
The lab contributes about $20 million to the local economy, according to UR estimates.
One of the petawatt laser's main jobs will likely be to supplement the $3.5 billion National Ignition Facility being built now at Lawrence Livermore National Laboratory in California, Sangster said. Livermore's 1.8 megajoule laser -- with power capacity far beyond UR's -- is expected to go online in about five years. Researchers will undoubtedly use UR's laser lab to "destroy all those who mocked" their research before annihilating Livermore, he said.
Not really news.. (Score:3, Interesting)
This isn't really news, being that the Vulcan laser in the UK reached petawatt capacity some months ago, after being awarded a grant for the purpose four years ago (see here [rl.ac.uk]) - the article doesn't mention the exact capacity, but I don't imagine that it's much more than a petawatt.
Another important thing to mention - again, not having read up on this - is that most scientific lasers are single-shot; most lasers are femto or petasecond lasers. From the same site as above (different news item [rl.ac.uk], "Over the course of the three year upgrade project, the output of Vulcan's ultra-short pulse beam will be increased to 500J in a pulse of 500fs duration giving a power on target of 1 Petawatt (1015 Watts)" - for many purposes, a laser such as Astra [rl.ac.uk] suits many peoples purposes; whilst the pulse energy for astra is
As far as military applications are concerned, as mentioned in other threads, this laser would almost certainly be useless; it would be far too hard to aim, and in any case, lasers like this reach sufficient power that they require nitrogen-filled tubing in many laboratories in order not to ionise the air under certain circumstances (which creates irritating popping noises) - there are certain other technical details (such as the beam type) which render them inefficient for military purposes (although one scientist working with astra and vulcan did want to shoot a beam into space with an encyclopedia encoded in the beam pulse in order to transmit data to potential victims of human first contact).
''Omega Laser''?? (Score:3, Funny)
Re:''Omega Laser''?? (Score:3, Funny)
That's ridiculous. The world will NOT be destroyed. A blue hedgehog in sneakers will show up at the right moment to stop it.
heh, but do *you* go to U of R? (Score:3, Funny)
What's to prevent me from being vaporized? huh?
Big laser (Score:4, Funny)
Just be sure to do a good job of guarding the exhaust port.
Oink! Oink! Pork alert (Score:3, Insightful)
The laser lab upgrade will add no more than a handful of jobs to the facility, which employs close to 250 full-time workers. But the petawatt will help ensure that federal money continues to flow to Rochester, McCrory said. "We could be a target ripe for closing if we don't stay technologically current," he said.
"Stockpile stewardship" is a code word for "keep people employed working on bomb-related stuff, even if we're not making any". Over at the Lawerence Livermore Senior Activity Center for Aging Physicists, it's their main mission. All the old guys who know how to design H-bombs will die off soon, and nobody will remember how to make them. It's been half a century since young smart people went into bomb design, after all.
Re:what if (Score:2)
Damnit, then Chairface [thetick.ws] will finally beat the tick by writing his name on the moon!!
Re:Had to say it... (Score:2, Funny)
Re:And... (Score:2)
Re:petawatt may sound good ... (Score:5, Interesting)
This laser (I can tell you without reading the article, as the laws of physics prevent the presumption) is only on for an EXTREMELY short duration, probably on the order of billionths of a second (that's 10E-9, for UK readers).
A peta-joule (as someone else pointed out) would be a LOT of coal. A petawatt for an extremely short duration isn't that much energy. Probably less than the entire university consumes for 1 second (I don't have accurate numbers on their power consumption, so don't micro analyze this statement).
The only use for such a short duration but high power laser is in physics experiments, and typically involves only a few dollars of electricity, so nearly no appreciable amount of coal or waste of any kind.
I'll pass on the political discussion though.
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Re:petawatt may sound good ... (Score:5, Informative)
A few years ago, I started a PhD in plasma physics, studying the high speed electron transport effects in short pulse, high intensity laser-plasma interactions. You are of course quite correct in your assertion that this sort of laser fires extremely brief pulses.
In plamsa physics, such a pulse is used to rapidly (read, near-instanteously) heat the surface of a target. The rapid heating causes the surface to ablate, which in turn causes the rest of the target to be compressed and heated. Get it right, and fusion ocurrs.
Quite apart from the physical reasons why you'd use a short pulse, the ultimate goal here is to create a viable method of producing energy. The more energy you put in at the start (by using a "long" laser pulse), the more you have to get out in the long run to make it worthwhile.
When I was still on my PhD (before I got bored and quit), we had a working z-pinch [ic.ac.uk] in the basement. As dramatic as it would have been for the lights to dim, there were no outward signs when it was fired
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fusion (Score:2)
Re:petawatt may sound good ... (Score:2, Interesting)
The energy used in this laser, as you said used "in a very short burst", would power a city, although just for a few milliseconds. Multiply that by the thousands of people in the city and you may not even have enough electricity to run my webserver for ten seconds (slashdotted or not). Warm those without roofs? What powers the sun? And what are the researchers trying to p
Re:petawatt may sound good ... (Score:5, Interesting)
In a word, magnets. The idea behind fusion, essentially, is that you raise a (hydrogen) plasma to sufficient temperature and pressure, and it will undergo fusion. If you get the conditions just right, it'll then continue to fuse once you've ignited it, thus supplying you with energy.
What you may not appreciate is that a plasma is electrically charged, and can therefore be contained using a suitable magnetic field. Arguably the most promising containment setup at the moment is the tokamak (from the Russian for bottle, iirc), which is a torus-shaped machine. Electromagnets around the torus create a circular magnetic field, which keeps the plasma contained in a ring. (My apologies if my information is out of date, I quit my PhD in plasma physics 4 years ago...)
Despite what the article says, however, fusion is not entirely pollution-free. One of the byproducts is a fairly large supply of neutrons. These neutrons are absorbed by the reactor, which will slowly but surely become radioactive. Therefore, you will eventually be left with radioactive waste to dispose of. You won't get anything like the quantity you get with fission, though, and fusion certainly doesn't produce any "conventional" pollution.
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Re:petawatt may sound good ... (Score:5, Informative)
I think they plan on dealing with this by using vanadium alloys. If you start with the most stable form of vanadium (V51) and bombard it with neutrons, the first neutron absorbed will cause a quick beta decay to Cr52. Fortunately, chromium has the same crystal structure as V, so you won't weaken the alloy much. Cr can absorb another 3 neutrons before it beta-decays to Mn55, which has a different crystal structure, so at that point, you might start causing enbrittlement of the alloy. However, Mn55 can absorb 5 more neutrons before you end up with an element that has a worrying half life (Co60).
So by picking your materials correctly, you can potentially avoid some of the problems associated with neutrons.
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Re:petawatt may sound good ... (Score:3, Funny)
That's still more recent than the last time I did plasma physics... which was never.
"...fusion certainly doesn't produce any "conventional" pollution."
You mean like cows? Good. One nuclear fart and we're all goners.
Re:Fuel cells? (Score:3, Insightful)
Nevermind the fact that even if we did somehow find a plentif