The Big Bang Experiment: In Photos and Videosby Stevie Smith - Sep 12 2008, 05:12
Inside the Large Hadron Collider. Image: CERN.');
Inside the Large Hadron Collider. Image: CERN.');
The four main points of interest that will be utilised during the LHC experiment.
ATLAS during its beam pipe installation.
ATLAS during the installation of its detector.
One of the ATLAS semi-conductor tracker barrels.
Inside the ATLAS solenoid cryostat.
Geneva:
It's being called a new beginning for our understanding of the universe
and particle physics. After lengthy delays the multi-billion dollar scientific
experiment to smash protons moving at near light-speed has been successful.
(Read: What the Big Bang experiment part 2 is)
The
experiment has taken place inside the world's largest and most powerful
particle accelerator near Geneva belonging to the European Organisation for
Nuclear Research (CERN). Inside the accelerator, two beams of particles travel
at close to the speed of light with very high energies before colliding with
one another.
Big Bang Experiment: Possible
Outcomes:
Researchers
to sift through sub-atomic debris of proton collisions
Could lead to
discovery of the Higgs boson (God particle)
New
discoveries about the laws of physics expected
Scientists
hope to make discoveries into mysterious dark matter
Scientists:
Dark matter makes galaxies spin faster
Hunt For 'God Particle':
The
hypothetical Higgs boson also called as the 'God particle'
Believed to
have existed when the universe was born
Discovery
would help explain origin of mass in universe
Scientists: Higgs is particle(s) that might give
others mass
Evidence to
prove Higgs exists still inconclusive
Goal:
To mimic
conditions moments after the Big Bang
To examine
nature of matter and the origin of stars, planets
Ultimate aim
to find Higgs boson, the so-called 'God particle'
How:
By colliding
protons moving at 99.999999% of the speed of light into each other
Proton beams
are collided in a particle accelerator called Large Hadron Collider
Large Hadron
Collider:
World's
biggest, most powerful particle accelerator
Consists of a
27-km ring of superconducting magnets
Operates at
Swiss-French border at a depth of 100 metres
The
experiment was delayed because of a problem detected in the huge underground
particle accelerator.
The $10
billion Large Hadron Collider directed the beams into each other Tuesday as
part of its ambitious bid to reveal details about theoretical particles and
microforces.
The
collisions herald a new era for researchers working on the machine in a 17-mile
(27-kilometer) tunnel below the Swiss-French border at Geneva.
"That's
it! They've had a collision," said Oliver Buchmueller from Imperial
College in London as people closely watched monitors.
In a control
room, scientists erupted with applause when the first successful collisions
were confirmed. Their colleagues from around the world were tuning in by remote
links to witness the new record, which surpasses the 2.36 TeV CERN recorded
last year.
Dubbed the
world's largest scientific experiment, scientists hope the machine can approach
on a tiny scale what happened in the first split seconds after the Big Bang,
which they theorize was the creation of the universe some 14 billion years ago.
The extra
energy in Geneva is expected to reveal even more about the unanswered questions
of particle physics, such as the existence of antimatter and the search for the
Higgs boson, a hypothetical particle that scientists theorize gives mass to
other particles and thus to other objects and creatures in the universe.
Tuesday's
initial attempts at collisions were unsuccessful because problems developed
with the beams, said scientists working on the massive machine. That meant that
the protons had to be "dumped" from the collider and new beams had to
be injected.
The
atmosphere at CERN was tense considering the collider's launch with great
fanfare on September 10, 2008. Nine days later, the project was sidetracked
when a badly soldered electrical splice overheated, causing extensive damage to
the massive magnets and other parts of the collider some 300 feet (100 meters)
below the ground.
It cost $40
million to repair and improve the machine. Since its restart in November 2009,
the collider has performed almost flawlessly and given scientists valuable
data. It quickly eclipsed the next largest accelerator -- the Tevatron at
Fermilab near Chicago.
Two beams of
protons began 10 days ago to speed at high energy in opposite directions around
the tunnel, the coldest place in the universe, at a couple of degrees above
absolute zero. CERN used powerful superconducting magnets to force the two beams
to cross, creating collisions and showers of particles.
"Experiments
are collecting their first physics data -- historic moment here!" a
scientist tweeted on CERN's official Twitter account.
"Nature
does it all the time with cosmic rays (and with higher energy) but this is the
first time this is done in Laboratory!" said another tweet.
When
collisions become routine, the beams will be packed with hundreds of billions
of protons, but the particles are so tiny that few will collide at each
crossing.
The
experiments will come over the objections of some people who fear they could
eventually imperil Earth by creating micro black holes -- subatomic versions of
collapsed stars whose gravity is so strong they can suck in planets and other
stars.
CERN and many
scientists dismiss any threat to Earth or people on it, saying that any such
holes would be so weak that they would vanish almost instantly without causing
any damage.
Bivek Sharma,
a professor at the University of California at San Diego, said the images of
the first crashed proton beams were beautiful.
"It's
taken us 25 years to build," he said. "This is what it's for. Finally
the baby is delivered. Now it has to grow." (With AP inputs)
Scientists
trying to the crack the fundamental laws of physics on Tuesday said they had
recreated in miniature the conditions just after the start of the universe,
without bringing the world to an end.
In a
groundbreaking moment, researchers operating the Large Hadron Collider near
Geneva combined two opposing beams of sub-atomic particles travelling at almost
the speed of light as they attempted to simulate events in the fraction of a
second after the “Big Bang”, the most widely accepted theory.
After several
false starts early on Tuesday, scientists just before 1pm local time brought
together the two proton beams that had been running in alternate directions in
the collider’s 27km loop in a vacuum at minus 271°C. The resulting heat was
equivalent to 100,000 times that generated by the sun.
The success
triggered rounds of applause and cheers from the scientists and journalists
gathered in the circular control room, while allaying concerns that the
experiment would create a black hole and destroy the universe.
Sixteen
months after glitches brought the collider’s first effort to a halt, the
breakthrough sparked worldwide interest, sharply slowing down a live webcast –
and briefly outranking the singer Ricky Martin, who declared his homosexuality
on Twitter during the day – as the collider recruited 100,000 Twitter
followers.
Rolf Heuer,
director-general of Cern, the European Laboratory for Particle Physics where
the collider project is based, said: “It’s a great day to be a particle
physicist. A lot of people have waited a long time for this moment, but their
patience and dedication is starting to pay dividends.”
The
breakthrough heralds the beginning of a new era in efforts to try to understand
profound scientific questions, including whether the sub-atomic particles –
quarks – inside the protons and neutrons can be freed; and why these latter
particles weigh some 100 times more than the quarks of which they are composed.
The protons
in the LHC, which requires 100 megawatts of power to operate, collided at more
than 7 tera – or trillion – electronvolts (TeV), a measure of energy given to
an electron as it accelerates through a potential of one volt. This was more
than triple the levels of previous experiments.
Nearly three
decades after the project was first discussed, and 15 years after construction
of the SFr6.5bn collider began, the breakthrough signals the start of at least
18 months of experiments at the current energy levels, and still longer periods
of analysis using “the Grid”, a vast international network of computers that
will process 15m gigabytes of data a year. A paper released by Cern earlier
this month concluded that “there can be little doubt that black hole production
at the [Large Hadron Collider] would be an unacceptable and irresponsible
risk”.
But officials
were quick to argue on Tuesday that neutron stars showed these conditions would
be safely reproduced in the collider.
“We are not
doing anything that nature has not done before,” said a spokeswoman. “Nature
shows us by the existence of neutron stars that we will not recreate black
holes.”
Experiments
with the Large Hadron Collider began in September 2008 but had to be halted
after a fault damaged the magnets in the equipment.
The original
objective was to reach 14 TeV, but in order to avoid a repetition of these
problems, researchers will operate the collider at half that level for 18
months before a technical shut down and analysis. An attempt to reach the
maximum level is only likely to take place in two or three years’ time.
Cern said it
would know by Wednesday the number of internet users who visited its website on
Tuesday to follow the project. The previous experiment in 2008 attracted 100m
users.
Once they
have “rediscovered” sub-atomic particles which have already been observed in
the so-called Standard Model, the four separate experiments associated with the
collider will start seeking the Higgs boson, a hypothetical elementary particle
– sometimes dubbed God’s Particle – which has been postulated as a means of
resolving inconsistencies in current theoretical physics to help explain the
origin of mass.
Largest machine, smallest
particles
● Although
built to study the smallest known building blocks of all things – particles –
the Large Hadron Collider is the largest and most complex machine ever made. It
contains 9,300 magnets and has a circumference of 27km (17 miles)
● At full
power, trillions of protons race around the LHC accelerator ring 11,245 times a
second, travelling at 99.99 per cent of the speed of light. It is capable of
engineering 600m collisions every second
● To avoid
colliding with gas molecules inside the accelerator, the beams of particles
travel in an ultra-high vacuum – a cavity as empty as interplanetary space
● The cooling
system circulates super-fluid helium around the LHC’s accelerator ring and
keeps the machine at minus 271.3 degrees Celsius
● When two
beams of protons collide, they generate temperatures more than 100,000 times
hotter than the heart of the sun, concentrated within a miniscule space
● To collect
data of up to 600m proton collisions per second, physicists and scientists have
built electronic trigger systems to measure the passage time of a particle to a
few billionths of a second
● The data
recorded by the LHC’s big experiments will fill about 100,000 dual-layer DVDs
every year. Tens of thousands of computers have been harnessed in a network
called The Grid that will hold the information
● Thousands
of scientists around the world will collaborate on analysing the data over the
next 15 years (the estimated lifetime of the LHC)
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