http://www.chinadaily.com.cn/china/2012-07/10/content_15562901.htm
For years, deep in an underground European laboratory, Chinese physicists have been contributing to one of the most ambitious scientific experiments ever attempted — a search for the missing link at the beginning of the universe.
"How do we seize Higgs boson?" said Chen Guoming, a researcher at the Institute of High Energy Physics at the Chinese Academy of Sciences.
"We copy the starting moment of the universe."
This undated image made available by the European Organization for Nuclear Research shows a typical candidate event including two high-energy photons whose energy (depicted by red towers) is measured in the CMS electromagnetic calorimeter. The yellow lines are the measured tracks of other particles produced in the collision. The pale blue volume shows the CMS crystal calorimeter barrel. Scientists at the world's biggest atom smasher claimed the discovery of a new subatomic particle on July 4, calling it "consistent" with the long-sought Higgs boson — popularly known as the "God particle" — that helps explain what gives all matter in the universe size and shape. [Photo/Agencies]
Chen was one of 3,000 scientists from 175 universities or research institutions in 38 countries and regions who have spent several years re-creating mini Big Bangs in a 100-meter underground laboratory on the French-Swiss border in an attempt to find the elusive particle.
Better known as the "God particle", it is the crucial link that could explain why other elementary particles have mass.
Last week, in a major scientific breakthrough, scientists at the European Organization for Nuclear Research, better known as CERN, announced they had found a particle consistent with the Higgs boson, an announcement greeted with great fanfare in the scientific community across the globe.
CERN conducted two major experiments focused on finding the Higgs boson — CMS and ATLAS. Thirty scientific researchers from China, representing the Institute of High Energy Physics of the Chinese Academy of Sciences and Peking University, took part in the search for the particle.
On July 4, CERN announced the CMS and ATLAS experiments had observed a new particle that was consistent with the Higgs particle.
"It's hard not to get excited by these results," said CERN Research Director Sergio Bertolucci.
"We stated last year that in 2012 we would either find a new Higgs-like particle or exclude the existence of the Standard Model Higgs. With all the necessary caution, it looks to me that we are at a branching point: the observation of this new particle indicates the path for the future toward a more detailed understanding of what we're seeing in the data."
Two parts of colliding points of the Large Hadron Collider teeth together in the European Organization for Nuclear Research in Geneva in 2006. Chinese scientists participated in the building of the collider that plays an important role in the finding of the Higgs boson. PROVIDED TO CHINA DAILY
The Higgs boson is named after British physicist Peter Higgs who, along with others, proposed the mechanism that suggested such a particle existed in 1964 — a theory ridiculed by some of the most respected minds of the time.
Stephen Hawking even bet another renowned physicist, Gordon Kane of the University of Michigan, $100 that the Higgs particle would not be found.
"It seems I have just lost $100," Hawking was quoted saying in London newspaper The Daily Telegraph following CERN's breakthrough.
Last week, Higgs, 83, traveled to Switzerland to witness the landmark announcement. The octogenarian was visibly moved as the presentation finished to tumultuous applause from a wildly excited audience, some of whom had waited overnight to secure their seats.
Choking back tears, Higgs paid tribute to the scientists who worked on the project.
"I would like to add my congratulations to everyone involved in this achievement. It's really an incredible thing that it's happened in my lifetime," Higgs said.
The CMS program cost about 500 million Swiss francs ($511.47 million), of which China contributed 1 percent.
China built the Resistive Plate Chamber, one-third of the Cathoed Strip Chamber, and supplied materials to help build part of a device called an electromagnetic calorimeter.
The experiment was carried out in the $511 million Large Hadron Collider, a huge device mainly made up of a 27 km ring of powerful magnets. Protons are placed into the collider and made to speed up before crashing together. Particle detectors in the machine read the data.
"Let's assume that you have two crystal balls, both composed of some inner structures you do not know. If you clash the two, they break apart into pieces, and then you can see what is in it," Chen said.
"That is like what we did on Large Hadron Collider, only it is much more difficult," he said.
"Actually the chance of finding Higgs boson is so rare that you could have 1 trillion collisions and you get one Higgs boson."
One barrier faced by the scientists was that the collision produced other particles called hadron and quantum photon. The scientists had to find a way to distinguish the particles from each other in order to find the Higgs boson.
"Chinese scientists found a unique method to distinguish the two particles, which was better than the solution of any other team. So our method was used for this and helped find the hint of Higgs boson," Chen said.
CERN is not the first group of scientists to search for the Higgs boson.
Before the Large Hadron Collider was switched on in 2008, the Tevatron in the United States was the most powerful collider in the world and in its final years of operation, raced to catch the first glimpse of the Higgs boson.
Although Tevatron was closed in 2011 due to budget constraints, the scientists involved in that project announced in March they had found evidence of a new fundamental particle that had a mass that fit in with predictions for the Higgs boson and was similar to experimental evidence announced by the Swiss-based scientists in December.
（China Daily，2012-07-10）
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