When you shoot laser through a gold bit the size of a pinhead, suddenly more than 100 billion particles of anti-matter materialise.
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 lab opens the door to several fresh avenues of anti-matter research, including an understanding of the physics underlying phenomena such as black holes and gamma ray bursts.
Anti-matter research also could reveal why more matter than anti-matter survived the Big Bang at the start of the universe.
'We've detected far more anti-matter than anyone else has ever measured in a laser experiment,' said Hui Chen, Lawrence Livermore National Lab researcher who led the experiment. 'We've demonstrated the creation of a significant number of positrons using a short-pulse laser.'
Chen and her colleagues used a short, ultra-intense laser to irradiate a millimeter-thick gold target. 'Previously, we concentrated on making positrons using paper-thin targets,' said Scott Wilks, who designed and modelled the experiment using computer codes.
'But recent simulations showed that millimeter-thick gold would produce far more positrons. We were very excited to see so many of them,' he said.
In the experiment, laser ionises and accelerates electrons, which are driven right through the gold target. On their way, the electrons interact with the gold nuclei, which serve as a catalyst to create positrons.
The electrons give off packets of pure energy, which decays into matter and anti-matter, following the predictions by Einstein's famous equation that relates matter and energy, said a Livermore release.
By concentrating the energy in space and time, the laser produces positrons more rapidly and in greater density than ever before in the laboratory.
Particles of anti-matter are almost immediately annihilated by contact with normal matter, and converted to pure energy (gamma rays).
There is considerable speculation as to why the observable universe is apparently almost entirely matter, whether other places are almost entirely anti-matter, and what might be possible if anti-matter could be harnessed.
Normal matter and anti-matter are thought to have been in balance in the very early universe, but due to an 'asymmetry' the anti-matter decayed or was annihilated, and today very little anti-matter is seen.
Chen presented her work at the American Physical Society's Division of Plasma Physics meeting in Dallas.
Scientists develop mother of all laser beams
New York, Feb 19 (IANS) Scientists have developed the mother of all laser beams - one that has focussed power equal to all the sunlight heading earth's way.
Researchers at the University of Michigan recently created the record-setting beam, which measures 20 billion trillion watts per square centimetre, Sciencedaily reported.
'I don't know of another place in the universe that would have this intensity of light. We believe this is a record,' said Karl Krushelnick, who was part of the team that created the laser.
The laser contains 300 terawatts of power, or 300 times the capacity of the entire US electricity grid, and its power is concentrated in a 1.3-micron speck - about one-100th the diameter of a human hair.
Of course, a beam like this cannot be sustained for long. This one lasted just 30 femtoseconds. A femtosecond is a millionth of a billionth of a second, the researchers said in a paper published in the online edition of the journal Optics Express.
Such intense beams could help scientists develop better proton and electron beams for radiation treatment of cancer, among other applications.
The laser can produce this intense beam once every 10 seconds, whereas other powerful lasers can take an hour to recharge.
The team managed to get such high power by putting a moderate amount of energy into a very, very short time period.
In addition to medical uses, intense laser beams like these could help researchers explore new frontiers in science.
At even more extreme intensities, laser beams could potentially 'boil the vacuum', which scientists theorise would generate matter by merely focussing light into empty space.
Some scientists also see applications in inertial confinement fusion research, coaxing low-mass atoms to join together into heavier ones and release energy in the process.
Researchers at the University of Michigan recently created the record-setting beam, which measures 20 billion trillion watts per square centimetre, Sciencedaily reported.
'I don't know of another place in the universe that would have this intensity of light. We believe this is a record,' said Karl Krushelnick, who was part of the team that created the laser.
The laser contains 300 terawatts of power, or 300 times the capacity of the entire US electricity grid, and its power is concentrated in a 1.3-micron speck - about one-100th the diameter of a human hair.
Of course, a beam like this cannot be sustained for long. This one lasted just 30 femtoseconds. A femtosecond is a millionth of a billionth of a second, the researchers said in a paper published in the online edition of the journal Optics Express.
Such intense beams could help scientists develop better proton and electron beams for radiation treatment of cancer, among other applications.
The laser can produce this intense beam once every 10 seconds, whereas other powerful lasers can take an hour to recharge.
The team managed to get such high power by putting a moderate amount of energy into a very, very short time period.
In addition to medical uses, intense laser beams like these could help researchers explore new frontiers in science.
At even more extreme intensities, laser beams could potentially 'boil the vacuum', which scientists theorise would generate matter by merely focussing light into empty space.
Some scientists also see applications in inertial confinement fusion research, coaxing low-mass atoms to join together into heavier ones and release energy in the process.
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