World's strongest laser unveiled at California lab

Discussion in 'International Politics' started by Rage, Jun 1, 2009.

  1. Rage

    Rage DFI TEAM Stars and Ambassadors

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    World's strongest laser unveiled at California lab

    1 Jun 2009, 0333 hrs IST, AP

    [​IMG]
    Three football fields could fit inside the NIF Laser and Target Area Building.


    LIVERMOREC (California): The world's most powerful laser, created to help keep tabs on the US nuclear weapons stockpile while also studying the heavens, has been unveiled.

    The super laser, known officially as the National Ignition Facility, was unveiled on Friday at the Lawrence Livermore National Laboratory about 50 miles (80 kilometers) east of San Francisco.

    California Gov. Arnold Schwarzenegger and US Sen. Dianne Feinstein were among thousands of people in attendance at the ceremony.

    The NIF*, which is the size of a football field, consists of 192 separate laser beams, each traveling 1,000 feet (304.8 meters) in one-thousandth of a second to converge simultaneously on a target the size of a pencil eraser.

    Federal officials said they planned to use it on a multifaceted assignment that would include ensuring aging nuclear weapons are functioning properly without resorting to underground testing.

    Other uses will include the study of astrophysics and experiments in developing green energy programs.

    Beginning next year, scientists also will use the laser for experiments aimed at creating controlled fusion reactions similar to those found in the sun.

    ``More energy will be produced by this ignition process than the amount of laser energy required to start it. This is the long-sought goal of energy gain that has been the goal of fusion researchers for more than half a century,'' said NIF director Edward Moses.

    The laser will be used in astrophysics, allowing scientists to mimic conditions inside planets and new solar systems, something the lab's officials said would allow for conducting experiments that could never be undertaken on Earth before.


    World's strongest laser unveiled at California lab - Science - Health & Science - The Times of India


    *Acronyms: NIF- National Ignition Facility
    ** Image courtesy: lasers.llnl.gov
     
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  3. Rage

    Rage DFI TEAM Stars and Ambassadors

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    NIF: The ‘Crown Joule’ of Laser Science


    The National Ignition Facility (NIF) is the world's largest laser. NIF's 192 intense laser beams will deliver to its target more than 60 times the energy of any previous laser system. When all 192 beams are operational in 2009, NIF will direct nearly two million joules of ultraviolet laser energy in billionth-of-a-second pulses to the target chamber center.

    When all that energy slams into millimeter-sized targets, it can generate unprecedented temperatures and pressures in the target materials – temperatures of more than 100 million degrees and pressures more than 100 billion times Earth's atmosphere. These conditions are similar to those in the stars and the cores of giant planets or in nuclear weapons; thus one of the NIF & Photon Science Directorate's missions is to provide a better understanding of the complex physics of nuclear weapons. Researchers can also explore basic science, such as astrophysical phenomena, materials science and nuclear science (see Understanding the Universe). NIF's other major mission is to provide scientists with the physics understanding necessary to create fusion ignition and energy gain for future energy production.

    NIF encompasses three interconnected buildings: the Optics Assembly Building, the Laser and Target Area Building, and the Diagnostics Building. Inside the Optics Assembly Building large, precision-engineered laser components are assembled under stringent cleanroom conditions into special modules called line replaceable units, or LRUs, for installation into the laser system.

    [​IMG]
    Laser Bay 2, one of NIF's two laser bays, was commissioned on July 31, 2007

    The Laser and Target Area Building houses the 192 laser beams in two identical bays. Large mirrors, specially coated for the laser wavelength and mounted on highly stable ten-story-tall structures, direct the laser beams through the "switchyards" and into the target bay. There they are focused to the exact center of the ten-meter-diameter, concrete shielded, one-million-pound target chamber. Construction of all the buildings and supporting utilities was completed in September 2001. All 192 enclosures for laser beams were completed in 2003.

    Operation of NIF's extraordinarily energetic laser beams requires that everything in the beam's enclosures remain perfectly clean at all times. Any bit of debris, oil, or other wayward material could cause the intense light to damage the optics. The space inside the beam enclosures typically exceeds the cleanliness of a semiconductor or pharmaceutical manufacturing plant.


    Extraordinary Precision

    Every NIF experimental shot requires the coordination of up to 60,000 control points for electronic, high voltage, optical and mechanical devices – motorized mirrors and lenses, energy and power sensors, video cameras, laser amplifiers and diagnostic instruments. Achieving this level of precision requires a large-scale computer control system as sophisticated as any in government service or private industry. The meticulous orchestration of these parts will result in the propagation of 192 separate nanosecond (billionth of a second)-long bursts of light over a one-kilometer path length. The 192 separate beams must have optical pathlengths equal to within nine millimeters so that the pulses can arrive within 30 picoseconds (trillionths of a second) of each other at the center of the target chamber. Then they must strike within 50 micrometers of their assigned spot on a target the size of a pencil eraser. NIF's pointing accuracy can be compared to standing on the pitcher's mound at AT&T Park in San Francisco and throwing a strike at Dodger Stadium in Los Angeles, some 350 miles away. Because the precise alignment of NIF's laser beams is extremely important for successful operation, the requirements for vibrational, thermal and seismic stability are unusually demanding. Critical beampath component enclosures (generally for mirrors and lenses), many weighing tens of tons, were located to a precision of 100 microns using a rigorous engineering process for design validation and as-installed verification.


    Why Are There 192 Beams?

    Imagine trying to squash a water balloon with two hands. No matter how hard you try to spread your fingers evenly over the surface of the balloon, it will still squirt out between your fingers. Many more fingers would be needed to compress the balloon symmetrically. Earlier high-energy lasers were used to study the conditions required to compress tiny spherical capsules to fractions of their initial diameter while still maintaining the capsule's symmetry – a crucial requirement if NIF is to achieve fusion ignition. NIF's designers arrived at 192 focused spots as the optimal number to achieve the conditions that will ignite a target's hydrogen fuel and start fusion burn.


    A Variety of Experiments

    Not all experiments on NIF need to produce fusion ignition. Researchers are planning many other types of experiments that will take advantage of NIF's tremendous energy and flexible geometry in non-ignition shots. Non-ignition experiments will use a variety of targets to derive a better understanding of material properties under extreme conditions. These targets can be as simple as flat foils or considerably more complex. By varying the shock strength of the laser pulse, scientists can obtain equation-of-state data that reveal how different materials perform under extreme conditions for stockpile stewardship and basic science. They also can examine hydrodynamics, which is the behavior of fluids of unequal density as they mix.

    NIF experiments also will use some of the beams to illuminate "backlighter" targets to generate an X-ray flash. This allows detailed X-ray photographs, or radiographs, of the interiors of targets as the experiments progress. In addition, moving pictures of targets taken at one billion frames a second are possible using sophisticated cameras mounted on the target chamber. These diagnostics can freeze the motion of extremely hot, highly dynamic materials to see inside and understand the physical processes taking place. As construction of the 48 "quads" of four beams each proceeded, many shots were already being performed using the first quad of beams (see NIF Early Light). Experiments beginning in the winter of 2007-2008 will take advantage of additional quads as they come online.

    [​IMG]
    Technicians adjust the target positioner inside the NIF Target Chamber.


    New Technologies Make NIF Possible

    Amplifying NIF's beams to record-shattering energies, keeping the highly energetic beams focused, maintaining cleanliness all along the beam's path, and successfully operating this enormously complex facility – all required NIF's designers to make major advances in existing laser technology as well as to develop entirely new technologies. Innovations in the design, manufacture, and assembly of NIF's optics were especially critical.


    https://lasers.llnl.gov/programs/nif/about.php
     
  4. Rage

    Rage DFI TEAM Stars and Ambassadors

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    How NIF Works


    NIF's 192 laser beams travel a long path, more than 1,000 feet, from their birth at the master oscillator to the center of the target chamber. As the beams move through NIF's amplifiers, their energy increases exponentially. From beginning to end, the beams' total energy grows from one-billionth of a joule to four million joules, a factor of more than a quadrillion – and it all happens in less than two millionths of a second.


    [​IMG]

    Every NIF beam starts at the master oscillator (bottom center).
    The low-energy beam is amplified in the preamplifier module and then
    in the power amplifier, the main amplifier, and again in the power amplifier
    before the beam is run through the switchyard and into the target chamber.


    The master oscillator generates a very small, low-energy laser pulse. The pulse may range from 100 trillionths to 25 billionths of a second long, and has a specific temporal shape as requested by NIF experimenters. The low-energy pulse is split and carried on optical fibers to 48 preamplifier modules for initial amplification and beam conditioning. In the preamplifiers the energy is increased by a factor of ten billion to a few joules. The 48 beams from the 48 preamplifiers are then split into four beams each for injection into the 192 main laser amplifier beamlines.

    Each beam zooms through two systems of large glass amplifiers, first through the power amplifier and then into the main amplifier. In the main amplifier, a special optical switch called a plasma electrode Pockels cell (PEPC) traps the light, forcing it to travel back and forth four times through 11 sets of laser amplifier glass slabs before it can exit the main amplifier cavity. Without this optical switch, the NIF main laser building would have to be about 750 feet longer to achieve the same amplification.


    [​IMG]
    An optical switch is tested in cleanroom
    conditions in NIF's Optics Assembly Building.



    From the main amplifier, the beam makes a final pass through the power amplifier before speeding into the target chamber. As the pulse's energy is being amplified, a special deformable mirror and other devices ensure that the beams are of high quality, uniformity and smoothness.

    NIF's large glass amplifiers are unique. Other large laser systems use a series of amplifiers of increasing size to raise the beam's energy. NIF's amplifiers are all the same size and use more than 3,000 one-meter-long slabs of special phosphate glass doped with neodymium atoms.


    [​IMG]
    The NIF switchyard directs the 192 laser beams into the target chamber
    and the precision diagnostic system.


    A split second before the initial weak laser pulse begins life at the master oscillator, more than 7,500 two-meter-long flashlamps, powered by huge capacitors that store electricity, energize the neodymium atoms in the amplifier glass by bathing them in intense white light. When the laser beams leave the preamplifiers, the amplifiers are already powered up and ready to receive them. After passing through all the amplifiers, each NIF laser beam has been amplified to about 20,000 joules of energy.

    [​IMG]
    The target chamber is hoisted by a crane and
    prepared for installation in the NIF target bay.


    A complex system of special mirrors in two ten-story steel structures known as "switchyards" rearrange the parallel, linear array of 192 laser beams into a spherical configuration so that the beams can be focused into the center of the target chamber. Among the stiffest structures ever built, the switchyard's towers are built to resist vibration and are firmly anchored to the inside of the building's four-foot-thick reinforced concrete walls. Each beam passes through a final optics assembly that converts the wavelength of the laser from infrared to ultraviolet and is focused through a final focus lens onto a target located at the chamber's center. Targets are located with a precision that is measured in fractions of the thickness of a sheet of paper. The ability to achieve such precise alignment was demonstrated with the first four activated beams and with subsequent experimental tests as additional beams were brought online.


    https://lasers.llnl.gov/programs/nif/how_nif_works/
     
  5. p2prada

    p2prada Stars and Ambassadors Stars and Ambassadors

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    Fact: All that energy, it will be enough to heat a bucket of water in a fraction of a second and will consume as much electricity as Bangalore needs in a year.
     
  6. Sridhar

    Sridhar House keeper Moderator

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  7. badguy2000

    badguy2000 Respected Member Senior Member

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    well, I still think strongest laser in the world is still in China,controlled by PLA....
    the Laser is developed to shoot down satellite.
     
  8. p2prada

    p2prada Stars and Ambassadors Stars and Ambassadors

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    [sarc]I guess Chinese people have eaten grass to get that ability.[/sarc]

    You need power equal to 100 times the Earth's total power production, maybe more, if you want to put a dent on the thin Aluminium covering on the satellite, after crossing 36000km or even 200km. Grow up. Look up some facts about laser before coming up with BS. You will only embarrass your scientists.
     
  9. MMuthu

    MMuthu Regular Member

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    Wow.... Chinese are most clever people in the world..... They have best things in the world. Even the US and other EU nations are decades behind China.

    If China thinks for a second.... then all the other nations will fall in no time. Amazing... You have to be born like the chinese....
     
  10. EnlightenedMonk

    EnlightenedMonk Member of The Month JULY 2009 Senior Member

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    Any links to support your claims ???

    Stuff like "I think" doesn't hold any credence or weightage...

    I THINK I CAN POISON THE OCEAN BY PISSING IN IT :D:D:D:D

    See what I mean???
     
  11. Antimony

    Antimony Regular Member

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    Of course it is. But the catch is that when you destroy a satellite it explodes into a shower of M113 Gav1ns, which get deployed en masse in Mainland China.:2guns::113:

    nuff said:bye:
     

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