http://news.yam.com/afp/international/200809/20080910633401.html
大強子對撞機啟動 質子束幾周後開始對撞
法新社╱楊一峰 2008-09-10 19:50
（法新社日內瓦十日電）科學家說，世界上最強而有力的原子撞擊機「大強子對撞機（ＬＨＣ）」今天開始運作，這項任務旨在識破物質宇宙最大的奧秘。
在格林威治標準時間七時三十分（台灣時間下午三時三十分）過後不久，第一個質子束被注入大強子對撞機。這個超大型計畫花了將近二十年的時間才完成，是歷來最複雜及花費最大的科學實驗之一。
大強子對撞機計劃領導人艾萬斯說：「在注入質子束後，約五秒鐘才取得資料，」不久後，控制螢幕上的指示器閃爍，證實了這項注入。
這個大強子對撞機花費了六十億瑞士法郎（約一千六百九十五億新台幣）建造。
這項任務旨在解決一些物理學上最難以解決的謎，包括粒子為何有質量，解釋奇怪的「暗物質」和「暗能量」，以及是否有與我們所處空間並存的其他空間。暗物質和暗能量佔宇宙組成的百分之九十六。
在法國與瑞士交界下深處的環形隧道內，平行的質子束將被加速到接近光速。
超導磁鐵然後會引導質子束，讓它們在四個巨大的實驗室對撞，短暫地複製一百三十七億年前宇宙創生時的「大爆炸」情況。
一系列的偵測器將追蹤撞擊後所噴出的次原子碎粒，以尋找新粒子存在的證據。
今天的啟動，是漫長而謹慎的檢查設備和運作程序的作業的開始。
第一批質子束在隧道內被一段一段的攔阻，以確認監視系統是否正常運作。
科學家說，質子束可能在幾週後開始對撞。
http://news.yahoo.com/s/afp/20080910/sc_afp/sciencephysicscern_080910124459
Scientists' joy after world's greatest atom-smasher starts operations
by Richard Ingham
39 minutes ago
GENEVA (AFP) - Particle physicists were jubilant on Wednesday after the long-awaited startup of a mega-machine designed to expose secrets of the cosmos passed its first test with flying colours.
Cheers, applause and the pop of a champagne cork -- rather than the cataclysmic suck of a black hole, as doomsayers had feared -- marked the breakthrough at the European Organisation for Nuclear Research (CERN).
Robert Aymar, the organisation's director general, hailed it as a "historic day" for CERN and mankind's thirst for knowledge.
Humans have "a quest for (knowing) where they came from and where they should go, whether the Universe will end, and where the Universe will go in the future," he said.
Just after 0730 GMT, the first proton beam was injected into the Large Hadron Collider (LHV), a massive built 100 metres (325 feet) underground at CERN headquarter.
The mission aims at resolving some of the greatest enigmas in physics: whether a so-called "God particle" exists that would account for the nature of mass; an explanation for "dark matter" and "dark energy" that account for 96 percent of the cosmos; and whether other dimensions exist in parallel to our own.
In a 27-kilometre (16.9-mile) circular tunnel on the Swiss-French border, parallel beams of protons will be accelerated to nearly the speed of light.
Superconducting magnets will then steer the counter-rotating beams so that strings of protons smash together in four huge laboratories, fleetingly replicating the conditions that prevailed at the "Big Bang" that created the Universe 13.7 billion years ago.
Arrays of detectors will trace the sub-atomic rubble spewed out from the collision, looking for signatures of novel particles.
CERN scientists have dismissed fears that the process could create a "black hole" whose super-gravity would swallow the Earth.
Wednesday's startup marked the start of a long and cautious commissioning process to check equipment and operational procedures before these collisions can get underway.
The first batch of protons was halted, sector by sector, to verify that monitoring systems and the steering magnets were working properly. Their speed was purposely slowed for the inspection process.
The clockwise beam completed this first test lap in under an hour, causing an eruption of joy and an outbreak of bubbly in the control room.
"No-one would have imagined that this could have been done in less than an hour. It's phenomonenal, quite unbelievable," an operator told AFP. "We are very happy and proud."
By comparison, the predecessor to the LHC at CERN, the Large Electron Positron (LEP) collider, took 12 hours to achieve the same goal.
A test of the anticlockwise beam would take place later on Wednesday, scientists said.
LHC Project Leader Lyn Evans, who has been working on the collider for 14 years, said he felt a wave of relief after the protons had completed their first lap so smoothly.
"It's a machine of enormous complexity and things can go wrong at any time," he said.
Messages of congratulations flooded in from CERN's partners and rivals, including the legendary Fermilab particle physics lab near Chicago.
The LHC took nearly 20 years to complete and at six billion Swiss francs (3.76 billion euros, 5.46 billion dollars) is one of the costliest and most complex scientific experiments ever attempted.
When all is ready, the LHC will whizz two parallel beams, one clockwise and the other anticlockwise, around the tunnel at up to 11,000 laps per second before steering them into collisions into four chambers whose walls are swathed with detectors.
The first collisions are likely to start in several weeks, but only next year will the LHC be cranked up to its full capacity of 14 teraelectronvolts -- a massive amount of energy -- or seven times the record held by Fermilab.
Over the 10-15 years in which will the LHC will operate, masses of data will spew from these collisions and will be scrutinised by physicists around the world.
"It's about acquiring knowledge for humanity about the behaviour of fundamental matter," physicist Daniel Denegri told AFP. "We expect to make discoveries that could be rather spectacular."
The Holy Grail will be finding a theorised component called the Higgs Boson, which would explain how particles acquire mass. Believed to be ubiquitous -- yet also frustratingly elusive until now -- the Higgs has been dubbed the "God particle."
The giant machine was several times over its initial budget and began operations two years late.
Before the startup, Internet-driven rumours said the LHC would create black holes or a nasty hypothetical particle called a strangelet that would gobble up the planet.
CERN commissioned a panel to verify its safety calculations and France also carried out its own assessment.
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