未来能源探秘:世界最大激光器
发布: 2009-5-07 16:46 | 作者: cnnas | 来源: 大风车中英文门户网站社区
未来能源探秘:世界最大激光器
在劳伦斯·利弗莫尔国家实验室(LLNL)国家点火设施(NIF)的科学家，希望利用192个激光器和一个由400英尺长的放大器及滤光器阵列构成的装置，制造出一个像太阳或者爆炸的核弹一样的自维持聚变反应堆(self-sustaining fusion reaction)。最后一批激光器安装完毕后，《连线》网站记者参观了这个点火设施。观看看世界上最先进的科学设备。
1.美国“国家点火装置”
这个大部头看起来可能很像迈克尔·贝执导的《变形金刚》中的人物，但是这个大型机器很快就会成为地球上的恒星诞生地。
美国“国家点火装置” 位于加州，投资约合24亿英镑，占地约一个足球场大小。科学家希望该激光器能模仿太阳中心的热和压力。“国家点火装置”由192个激光束组成，产生的激光能量将是世界第二大激光器、罗切斯特大学的激光器的60倍。2010年，192束激光将被汇聚于一个氢燃料小球上，创造核聚变反应，打造出微型“人造太阳”，产生亿度高温。
It may look like one of Michael Bay's Transformers, but this mass of machinery could soon be the birthplace of a baby star right here on Earth.
Using 192 separate lasers and a 400-foot-long series of amplifiers and filters, scientists at Lawrence Livermore's National Ignition Facility (NIF) hope to create a self-sustaining fusion reaction like the ones in the sun or the explosion of a nuclear bomb — only on a much smaller scale.
Sci-fi-inspired End of Days jokes may follow this historic undertaking like they did for CERN's Large Hadron Collider, but the science behind this advanced laser system is profoundly serious.
"Completion of the NIF construction project is a major milestone for the NIF team, for the nation and the world," said Edward Moses, the facility's principal associate director for NIF and photon science. "We are well on our way to achieving what we set out to do — controlled nuclear fusion and energy gain for the first time ever in a laboratory setting."
The hope is that this reaction will release more energy than the lasers put into the target isotopes and perhaps redefine the global energy crisis in the process.
Wired.com visited the National Ignition Facility just as the final lasers were coming on line. Read on for a virtual tour of one of the most sophisticated scientific facilities on the planet.
庞大的靶室
在庞大的靶室里，192束激光束进入直径是33英尺的蓝色真空室，在那里跟一个胡椒瓶大小的目标物相撞。然后这些光束会以动力较低的红外线的形式，从该仪器的不同部位出来，这个部位跟DVD播放器的内部结构类似。接着激光经过一系列复杂的放大器、过滤器和镜子，以便变得足够强大和精确，可以产生自维持聚变反应堆。
Here in the enormous target chamber, the 192 laser beams enter the blue, 33-foot-in-diameter vacuum chamber (the blue hemisphere in the top photo connected to the metallic arms) where they will collide with a target roughly the size of a peppercorn.
The beams start out in a different part of the facility as lower powered infrared light, similar to what's inside your DVD player. Next, the lasers pass through a complex series of amplifiers, filters and mirrors (much of which you'll see later on in the gallery) in order to become powerful and precise enough to create self-sustaining fusion.
包含放射性氢同位素、氘和氚的铍球
这个铍球包含放射性氢同位素、氘和氚。科学家将利用这个系统的192个激光器产生的X射线轰击它。核子熔合的关键是有足够的能量把两个核子熔合在一起，在这项实验中用的是氢核子。由于把两个核子分开的斥力非常强，因此这项任务需要利用极其复杂的工程学和特别多的能量。
例如，在光束进入真空室(包含图片上方的目标物)之前，激光必须通过巨大的合成水晶，转变成紫外线。发射到真空室里的光束会进入一个被称作黑体辐射空腔(hohlraum)的豆形软糖大小的反射壳(reflective shell)里，光束的能量在这里产生高能X射线。从理论上来说，X射线的能量应该足以产生可以克服电磁力的热和压力，这样核子就能熔合在一起了。电磁力促使同位素的核子分开。
Smaller than a BB, the beryllium sphere containing the radioactive hydrogen isotopes, deuterium and tritium, will be bombarded with x-rays generated by the system's 192 lasers.
The trick to fusion is getting enough energy to fuse two nuclei together — in this case, the nuclei of hydrogen. Because the forces keeping the nuclei apart are so strong, the task requires extremely complex engineering and an insane amount of power.
For example, right before the beams enter the vacuum chamber which contains the target pebble pictured above, the lasers are converted to ultraviolet light by huge synthetic crystals. Once inside the chamber the beams enter a jellybean-sized reflective shell called a hohlraum (German for "hollow room") where the energy of the beams generates high power x-rays. Theoretically, the x-rays will be powerful enough to create enough heat and pressure to overcome the electromagnetic force that keeps the isotopes' nuclei separate, and the nuclei will fuse.
靶室顶部的起重机和气闸盖
在第一张照片的靶室顶上，是用来把底部仪器放入真空室的起重机和气闸盖。如果这个仪器产生作用，它将成为未来发电厂的前身，将提高科学家对宇宙里的力的理解。当常规核试验被禁止的时候，它还有助于我们了解核武器内部的工作方式。
Atop the target chamber pictured on the first page is a crane and airlock hatch for lowering equipment into the vacuum chamber.
If the experiment works it will be a precursor to the power plant of the future and improve scientists' understanding of the forces in our universe. In a time when conventional nuclear tests are banned, it could also provide valuable insight into the inner workings of nuclear weapons.
精密诊断系统
激光束将被发射到精密诊断系统里，以在它进入靶室以前，确定它能正常工作。
One laser beam feeds into the Precision Diagnostic System, which allows the laser to be sampled to make sure it is working properly before entering the target chamber.
激光间
在激光间(laser bay)里眺望，会看到国家点火设施的激光间2号向远处延伸超过400英尺，激光在从这里到达靶室的过程中，会被放大和过滤。过去35年间，科学家在劳伦斯·利弗莫尔国家实验室建设了另外3个激光熔合系统，然而它们都不能生成足够达到核子熔合的能量。第一个激光熔合系统——Janus在1974年开始运行，它产生了10焦耳能量。第二项试验在1977年实施，这个激光熔合系统被称作Shiva，它产生了10000焦耳能量。
最后一项实验在1984年实施，这个被称作Nova的激光熔合项目产生了30000焦耳能量，这也是它的制造者第一次相信通过这种方法可以实现核子熔合。国家点火设施科研组制造的这个最新系统有望产生180万焦耳紫外线能量，科学家认为这些能量已经足以在劳伦斯·利弗莫尔国家实验室里产生一个小恒星。
As seen from the laser bay overlook, NIF's Laser Bay 2 stretches over 400 feet into the distance where lasers are amplified and filtered on their way to the target chamber.
Three previous laser fusion systems have been built in the past 35 years at Livermore Lab, none of which produced enough energy to reach fusion. The first, Janus, went online in 1974. It created 10 joules of energy. The next experiment, in 1977, was a laser system known as Shiva, which achieved 10,000 joules.
Finally, in 1984, a project named Nova produced 30,000 joules, and it was the first time its creators actually believed there was a chance of fusion. This newest system by the NIF team is expected to create 1.8 million joules of ultraviolet energy, which scientists hypothesize will create a baby star in Livermore with positive power output.
磷酸盐放大玻璃
国家点火设施包含3000多块混合着钕的磷酸盐放大玻璃，这是在熔合试验中用来增加激光束的能量的一种基本材料。这些放大玻璃板隐藏在密封的激光间周围的围墙里。
NIF contains more than 3,000 chunks of neodymium-doped phosphate amplifier glass — basically a material that increases the power of the laser beams used in the fusion experiment when energized by giant flashlamps. These amplifier glass slabs are hidden away inside airtight enclosures throughout the laser bay (above).
技术人员在激光间里安装光束管
技术人员在激光间里安装光束管，激光通过这些管会进入调试间。激光在调试间里会被重新改变运行路线，并重新排列，然后被输送到靶室里。
Technicians work on the beam tubes inside the laser bay that carry the lasers into the switchyard. From there they are redirected and aligned before entering the target chamber.
紧急停运盘
在整个国家点火设施里，标明激光位置的紧急停运盘(emergency shutdown panels)，可在激光发射时，为那些在错误的时间站在错误的地方的科学家和技术人员提供安全保障。
Throughout the entire NIF facility, emergency shutdown panels listing the status of the laser (using both text and light) provide a level of safety for the hapless scientist or technician who happens to be in the wrong place at the wrong time before a firing of the lasers.
光导纤维
光导纤维(黄色电缆部分)把低能激光传输到能量放大器里。然后在通过混有钕的合成磷酸盐的过程中，利用强大的频闪放电管放大。
Fiber optic strands (yellow cables and trough) feed low-powered laser light into the power amplifiers. There, they will be amplified by powerful strobes as they pass through synthetic neodymium-doped phosphate glass (the pink glass pictured on above).
能量放大器
能量放大器隐藏在天花板上的金属覆盖物下面，它含有可增大激光能量的玻璃板。在激光刚刚进入放大玻璃前，灯管把能量吸入玻璃里，接着激光束会获得这些能量。
The power amplifiers hidden by the metallic covers on the ceiling contain the glass slabs which greatly increase the power of the laser. Just before the laser enters the amplifier glass, flashlamps pump energy into the glass, which is then picked up by the laser beam.
可变形的镜子
可变形的镜子隐藏在天花板上覆盖的银膜下面，这种镜子是被用来塑造光束的波阵面，并弥补它在进入调试间前出现的任何缺陷。每个镜子利用39个调节器改变镜子表面的形状，纠正出现错误的光束。你在照片中看到的电线是用来控制镜子的调节器的。
Deformable mirrors hidden away above the silver covers on the ceiling are used to shape the beam's wavefront and compensate for any flaws before it enters the switchyard. Each mirror uses 39 actuators to change the shape of the mirror's surface and correct the beam. The wires you see here are used to control the mirror actuators.
激光放大器
激光束在进入主放大器和能量放大器前，较低前置放大器会放大激光束，并给它们塑形，让它们变得更加流畅。
The Lower Preamplifiers amplify, shape and smooth the laser beams before sending them off to the main and power amplifiers.
便携式洁净室
科学家利用一个独立的便携式洁净室(CleanRoom)运输和安置能量放大器和其他元件，这个洁净室就像用来装配微芯片的小室。
The power amplifiers and other components are transported and installed using a stand-alone, portable cleanroom, like the ones used to assemble microchips.
能量放大器
每个能量放大器都被安装在洁净室附近，然后利用遥控运输机把它们运输到梁线所在处。
技术人员校对能量放大器
从照片中可以看到，能量放大器在被放入梁线以前，技术人员正在对它进行校对。
A technician calibrates a power amplifier before it is placed into the beamline.
模仿NASA的主控室
照片中的主控室看起来跟美国宇航局的任务控制中心很相似，这是因为前者是模仿后者建造的。国家点火设施并不是利用这个主控室把火箭发射到外太空，而是设法通过激光，利用它把恒星的能量(核子熔合)带回地球。
The main control room looks similar to NASA's mission control for a reason: it was modeled after it. Instead of launching rockets into outer space, NIF will be attempting to bring the power of the stars — nuclear fusion – to Earth with lasers.
光束源控制中心
光束源控制中心即已知的主控振荡器室，看起来跟数据中心(Server Farm)很像，但是这个控制中心不是利用电脑，而是安装了一排排架子。光束通过光纤前往能量放大器的过程中，看起来就像网络供应商使用的网络。
The control center for the beam source, known as the master oscillator room, looks similar to a server farm, but instead of computers, racks of laser equipment fill the room. Like the network your internet provider uses, the beams travel through optical fibers on their way to the power amplifiers.
国家点火设施的激光源
国家点火设施的激光是从一个相对较小、能量较低，并且比较呆板的盒子里发射出来的。这个激光器呈固体状态，跟传统激光指示器没有多大区别，不过它们发射的光波波长不一样，前者是红外线，后者是可见光。
The NIF lasers start out in relatively small, low-powered and boring boxes (below and on the edge of the optic bench at right). The lasers are solid state and not much different than a standard laser pointer, albeit a different wavelength — infrared instead of visible.
高能灯管
高能灯管(flashlamps)跟照相机里的灯管一样，但是前者的体积超大，它可以用来激发激光。每束光束刚产生时，强度仅跟你的激光指示器发出的激光强度一样，但是它们在二十亿分之一秒内，强度就能曾大到500太拉瓦，大约是美国能量输出峰值时功率的500倍。
这一结果是能实现的，因为该实验室里拥有巨大的电容器，里面储存了大量能量。这个电容器非常危险，当它充电后，这个房间将被封闭，禁止任何人靠近，以免出现高压放电现象，伤着来访的人。
国家点火设施的外面看起来很像《半条命(Half-Life)》的拍摄现场，这种普通的外观掩饰了在里面进行的历史性科学研究。(孝文)
High-power flashlamps, like the one in your camera but super-sized, are used to excite the lasers. Each beam starts out about as strong as the one in your laser pointer, but all together they end up pumping out 500 terawatts in two billionths of a second — roughly 500 times the entire peak power output of the United States.
This is possible because the lab's giant bank of capacitors stores up a reservoir of energy. The bank is also quite dangerous — while the capacitors are charged, the room that holds them is on lockdown due to the risk of high voltage arcing and potentially injuring any visitors.
Like a scene out of Half-Life, the exterior of the NIF facility belies the history-making science conducted within.