Focus Fusion Reaches One Billion degree Benchmark

Focus Fusion has had a paperaccepted for publication that confirms that they have achieved a key milestoneof 100keV.  The work itself was delayedmonths in order to produce more robust switching equipment.

The present anticipated timetable targets a successful test during the coming year, although equipmentissues can obviously arise anytime.  Thisis true for all development of course.

What is important for now is thatthis is in the bag and it will be published.

JANUARY 11, 2011

The article is particularly significant as the first peer-reviewed publicationof the basic theory guiding LPP's pursuit of useful fusion energy from thedense plasma focus, as well as featuring the first experimental results fromthe team's Focus Fusion-1 experimental device

JANUARY 04, 2011

In a breakthrough in the effort to achieve controlled fusion energy, a research team at Lawrenceville Plasma Physics,Inc. (LPP) in Middlesex, NJ, announced that they have demonstrated theconfinement of ions with energies in excess of 100 keV (theequivalent of a temperature of over 1 billion degrees C) in a dense plasma. They achieved this using a compact fusion devicecalled a dense plasma focus (DPF), which fits into a small room and confinesthe plasma with powerful magnetic fields produced by the currents in theplasma itself. Reaching energies over 100 keV is important in achieving along-sought goal of fusion research—to burn hydrogen-boron fuel. Hydrogen-boron, (also known by itstechnical abbreviation, pB11) is considered the ideal fusion fuel, since itproduces energy in the form of charged particles that can be directly converted toelectricity. This could dramatically cut the cost of electricity generation andeliminate all production of radioactive waste.

The dense plasma focus has been studied for over 40 years. However, LPP hasbeen able to make great strides since its ―Focus-Fusion-1 experimental devicestarted producing data in October, 2009, due to its unique, patented design.Most importantly, its electrodes, which produce the self-pinching action thatconcentrates the plasma and current, are much smaller than those of other DPFdevices with similar peak currents. The electrode assembly is only 4 inchesacross and less than 6 inches in length.

The fusion energy yields achieved in these experiments are still far less thanthe energy used to run the machines. However, LPP hopes to make rapid progressin the coming year when the machine will be running with hydrogen–boron fuelfor the first time.

Previous experiments by LPP and other researchers had observedthe high-energy ions, and had obtained evidence that they are confined in densehot spots of plasma, called plasmoids. But they could not rule out analternative hypothesis—that the fusion reactions observed were due to a beam ofions cruising unconfined through the diffuse background gas in the vacuumchamber of the experiment. This question is critical to the viability of theDPF as a fusion generator, because only if some ions are trapped, circulatingaround and around within a dense plasmoid, can they heat the fuel upsufficiently to ignite a self-sustaining burn that will consume most of thefuel in the plasmoids. A diffuse beam alone, traveling on a one-way tripthrough cold and much less-dense background plasma, will not be able to dothat.

The new research at LPP’s Middlesex laboratory has now ruled out this beam-onlyhypothesis by clearly showing that the ions are confined. This conclusion isbased on a combination of evidence from several experiments and instruments,obtained over the past nine months, which fit together like pieces of a jig-sawpuzzle. The detailed scientific results are being submitted for publication inPhysical Review Letters, a leading physics journal.

The evidence for ions with energies more than 100 keV was obtained in threeexperiments in late September and late October, and were replicated this week.These experiments used deuterium, a heavy isotope of hydrogen, as the fuel, asis standard in most fusion experiments. Researchers observed the neutronsemitted from fusion reactions occurring when the deuterium ions collided witheach other. By measuring the difference in the neutron arrival times at twodetectors set at different distances—11 meters and 17 meters—from the axis ofthe fusion device, the physicists could calculate the energy of the ions thatproduced them. The greater the spread in the neutrons’ arrival times, thegreater their range of velocities and thus the greater the range of velocitiesof the deuterium ions that fused to produce the neutrons. More velocity meansmore energy, so this is a measure of the ions’ energy. (See Figure 1.) Eric J.Lerner, LPP’s president and lead scientist, explains, ―In our best shot, onSeptember 29, we calculate the average ion energy at between 160 and 220 keV,so we feel confident in conservatively saying that ion energies are above 100keV.

Three other shots also exceeded 100 keV (the most recent on January 3, 2011),and these were the upper end of a continuous distribution of ion energies inmany other shots, not extreme outliers.

DECEMBER 22, 2010

It is shown that in contrastto the electric pulse power driven implosion of a single conical wire array,the implosion of a nested conical wire array with opposite alternate openingangles can lead to the generation of fast jets, with velocities of the order 10^8 cm/s. This technique canbe applied for the supersonic shear flow stabilization of a dense z-pinch, butpossibly also for the fast ignition of a pre-compressed dense deuterium-tritiumtarget.

Back in 1967, Winterberg had proposed to reach very large jet velocities by theimpact under a small angle of a projectile on a stationary solid target. Forimpact velocities of ~10^7 cm/s and an angle of less than 10 degrees, jetvelocities of the order 10^8 cm/s could be expected, as they are needed forimpact fusion. Projectile velocities of ~10^7 cm/s can in principle be reachedby the acceleration of a small superconductingsolenoid with a magnetic travelling waveaccelerator, but the length of such an accelerator was estimated to be of theorder 10 km. However, it has been shown that such velocities can also bereached over a distance of a few cm by the electric pulse power drivenimplosion of a cylindrical thin wire array. This raises the question if withthis technique jet velocities of the order 108 cm/s can be reached by theimplosion of a conical wire array with a small opening angle. It turns out thatthis is not possible, but possible with a nested conical wire array.

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