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Scientists produce 2 billion degrees Celsius


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Hi! Today after I logged on the internet a news artical opened my eyes

abit about some scientists in the U.S somehow were able

to create a tremendous amount of energy in the form of heat.

I thought It would be cool to post this to see some reactions from

people about this. I read it carefully, It's pretty cool!

But the even more interesting thing about the expirement was

the fact the scientists dont know how they did it!

They speculated it was some unknown energy that was the culprit.

 

Would be cool to know how it happened. :)

 

They used a Z - machine http://www.livescience.com/technology/050607_z_machine.html

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That’s a lot of heat I’ll give you that, the real interesting thing is they are not yet shure how they did it! This is really hot, fussion does not even create heat like that (Normally anyway). Does anyone know what temperature a supernova would reach? Would be really cool if we can ever reach temperatures that high :)

 

Cheers,

 

Ryan Jones

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hi wormholeman,

 

I started a thread about this 2 billion kelvin thing last month (some 10 days ago)

 

http://www.scienceforums.net/forums/showthread.php?t=18929

 

you might like to check it out. there is a nice picture of the Z machine that one of the commenters (Bascule, I think) contributed, and some discussion

 

you evidently missed that thread :)

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  • 3 weeks later...
Am I accurate to use the factor ten to the fourth between temperature and average energy? This would say 200 kilovolts.

 

to verify how accurate, one site that works is:

http://physics.nist.gov/cuu/Constants/

 

select "conversion factors for energy equivalents"

http://physics.nist.gov/cuu/Constants/energy.html

 

select convert eV to Kelvin

It says one eV is 1.16045 x 104 K

 

and who cares about 16% fudge, so yeah a factor of 10,000.

 

Maybe NIST is not the quickest site to use but it is very general purpose. It has values for all kinds of natural constants, not just common units conversions.

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  • 2 weeks later...

One thing I do not understand is, if stars can fuse hydrogen at a few hundred millions degrees, why doesn't the 2-3 billions degrees disentegrate the crap out of the local atoms. The article discussed how the wires lasted surprisingly longer than expected. I could melt the wire faster at 10,000K.

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What I was saying about nuclear disentregration, at the voltages used and the temperatures suggested, the atomic nuclei should become part of the plasma. Instead of chemical/atomic plasma it should be nuclear plasma.

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Steel is iron with a little carbon and traces of (?); iron has atomic no.26. Tungsten was used and has atomic no.74, quite dense. The point is that yes, this is all cooking up, way up! This must take z-pinch time which takes current pulsing time. What is this ramp-up time, microseconds?? Something gave positive feedback to a stage of final fireworks, which was how long? I'd guess nanoseconds or less. Think of the different phases everything goes through as it's heated drastically (even Insane_Alien's mother).

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they created that temperature by sending an extremely high voltage current into an extremely high resistance wire. It resisted the current, and when a wire resists a current it is mostly converted into heat energy.

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they created that temperature by sending an extremely high voltage current into an extremely high resistance wire. It resisted the current, and when a wire resists a current it is mostly converted into heat energy.

How long does the wire last? Don't forget there is a strong z-pinch going on, where the axial current pulls moving charges inward. This is more than a toaster.

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Norman Alber, I think it lasted approximately 14 nanoseconds. Here is the whole story below, quote from http://www.physlink.com/News/060312SandiaZ.cfm :

 

Sandia’s Z machine has produced plasmas that exceed temperatures of 2 billion degrees Kelvin — hotter than the interiors of stars.

 

The unexpectedly hot output, if its cause were understood and harnessed, could eventually mean that smaller, less costly nuclear fusion plants would produce the same amount of energy as larger plants.

 

The phenomena also may explain how astrophysical entities like solar flares maintain their extreme temperatures.

 

The very high radiation output also creates new experimental environments to help validate computer codes responsible for maintaining a reliable nuclear weapons stockpile safely and securely — the principal mission of the Z facility.

 

'At first, we were disbelieving,' says Sandia project lead Chris Deeney. 'We repeated the experiment many times to make sure we had a true result and not an ‘Ooops’!'

 

The results, recorded by spectrometers and confirmed by computer models created by John Apruzese and colleagues at Naval Research Laboratory, have held up over 14 months of additional tests.

 

A description of the achievement, as well as a possible explanation by Sandia consultant Malcolm Haines, well-known for his work in Z pinches at the Imperial College in London, appeared in the Feb. 24 Physical Review Letters.

 

Sandia is a National Nuclear Security Administration laboratory.

 

What happened and why?

 

Z’s energies in these experiments raised several questions.

 

First, the radiated x-ray output was as much as four times the expected kinetic energy input.

 

Ordinarily, in non-nuclear reactions, output energies are less — not greater — than the total input energies. More energy had to be getting in to balance the books, but from where could it come?

 

Second, and more unusually, high ion temperatures were sustained after the plasma had stagnated — that is, after its ions had presumably lost motion and therefore energy and therefore heat — as though yet again some unknown agent was providing an additional energy source to the ions.

 

Sandia’s Z machine normally works like this: 20 million amps of electricity pass through a small core of vertical tungsten wires finer than human hairs. The core is about the size of a spool of thread. The wires dissolve instantly into a cloud of charged particles called a plasma.

 

The plasma, caught in the grip of the very strong magnetic field accompanying the electrical current, is compressed to the thickness of a pencil lead. This happens very rapidly, at a velocity that would fly a plane from New York to San Francisco in several seconds.

 

At that point, the ions and electrons have nowhere further to go. Like a speeding car hitting a brick wall, they stop suddenly, releasing energy in the form of X-rays that reach temperatures of several million degrees — the temperature of solar flares.

 

The new achievement — temperatures of billions of degrees — was obtained in part by substituting steel wires in cylindrical arrays 55 mm to 80 mm in diameter for the more typical tungsten wire arrays, approximately only 20 mm in diameter. The higher velocities achieved over these longer distances were part of the reason for the higher temperatures.

 

(The use of steel allowed for detailed spectroscopic measurements of these temperatures impossible to obtain with tungsten.)

 

Haines theorized that the rapid conversion of magnetic energy to a very high ion plasma temperature was achieved by unexpected instabilities at the point of ordinary stagnation: that is, the point at which ions and electrons should have been unable to travel further. The plasma should have collapsed, its internal energy radiated away. But for approximately 10 nanoseconds, some unknown energy was still pushing back against the magnetic field.

 

Haines’ explanation theorizes that Z’s magnetic energies create microturbulences that increase the kinetic energies of ions caught in the field’s grip. Already hot, the extra jolt of kinetic energy then produces increased heat, as ions and their accompanying electrons release energy through friction-like viscous mixing even after they should have been exhausted.

 

High temperatures previously had been assumed to be produced entirely by the kinetic flight and intersection of ions and electrons, unaided by accompanying microturbulent fields.

 

Z is housed in a flat-roofed building about the size and shape of an aging high-school gymnasium.

 

This work has already prompted other studies at Sandia and at the University of Nevada at Reno.

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Excellent, Ragib. Do we expect no nuclear reactions here? If temperature is 2 billion degrees, say, average energy is 200,000 EV, and we are looking at ion temperatures sustaining this for a surprising number of nanoseconds. The mass-energy of electrons is twice the typical gamma energy being seen here, or 0.511 MEV.

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Umm...forgive me, are u insulting me? i cant tell...well lets pretend u arent. Nuclear reactions do not occur with only heat, you require a certain amount of force, not given in this case. The filament almost immediately turned into plasma, then slowly cooled. I guess when i said 14 nanoseconds, i meant how long it sustained that heat. But, if you mean, how long it was solid before turning into plasma, very little i can only presume...

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I am simply talking shop. You say nuclear reaction requires force and I disagree. It requires energy to overcome reaction thresholds. In controlled fusion we heat the plasma to the point that protons hit each other sufficiently hard to fuse. In fission we assemble enough atoms in proximity that random neutron emissions stimulate chain reaction. Forces involved are incidental: slamming together fragments of the critical mass (not needed in a reactor), or confining a plasma (relevant in z-pinch and in tokomak machines, but not in the multiple laser approach).

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Steel is iron and some carbon and small amounts of other possible additions. I recall that iron is at the center of the "nuclear periodic table" in the sense that both fission and fusion stop here. There is no further energy to be found. Any reactions would involve carbon or anything else in this soup. Remember that carbon takes part in the later fusion cycles in stars. Can we rule out the presence of hydrogen? Is the experiment in vacuum and is there no significant presence of hydrogen? . . . . . . . . . . Checking Wikipedia for 'carbon burning': "The carbon burning process is a nuclear fusion reaction that occurs in massive stars (at least 4 MSun at birth) that have used up the lighter elements in their cores. It requires high temperatures (6×108 K) and densities (about 2×108 kg/m3)". We are dealing with enough kinetic energy (temperature) so some amount of fusion should be expected, depending upon density.

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