Last week it was
announced that the particle beams had fully circulated around the LHC
for the first time in over a year. The accelerator had been
this August due to damage. A bad
electrical connection had caused extensive damage and forced a
shutdown last Fall, and intensive repair process was delayed
by the winter.
With repairs at last complete, and beams
circulated, this week researchers decided to bump the testing up
To gain a proper perspective on these
collisions, it's first important to understand how they work.
Housed 100 meters under the Franco-Swiss border, the LHC sends proton
beams hurtling in opposite directions down a 17-mile-long track at
close to the speed of light. The beams are bent in the proper
direction by over 1,200 massive superconducting magnets. The beams
cross at allotted spots, and the protons contain within collide.
The results are captured by four advanced detectors bordering the
crossing points -- ATLAS,
the Compact Muon Solenoid (CMS), Alice and LHCb. Atlas and CMS
are general purpose detectors, while the remaining two are special
On Monday, coinciding with a CERN press
conference, at 1322 GMT the Atlas detector became the accelerator's
first to record
a collision. The Alice and LHCb recorded collisions at 1600
GMT. And with a bit of tweaking collisions were recorded by the
Compact Muon Solenoid detector at 1800 GMT.
Gianotti, spokesperson for the Atlas scientific team comments, "This
is great news, the start of a fantastic era of physics and hopefully
discoveries after 20 years' work by the international
CERN's director-general Rolf Heuer comments,
"It's a great achievement to have come this far in so short a
time. But we need to keep a sense of perspective - there's
still much to do before we can start the LHC physics programme."
collider already offers an extreme environment, with particles moving
at close to the speed of light and temperatures of 1.9 degrees
Kelvin. While some might wonder why those temperatures are
necessary, they're designed to simulate conditions at the time of the
Big Bang, the cosmological event that created the universe as we know
However, in order to get closer to these
conditions, the energy of the beams will need to be bumped up from
low-to-moderate power to 7 TeV (14 TeV combined). A flying
mosquito has approximately 1 TeV of kinetic energy. While "14
mosquitos" worth of combined energy may not seem like much, its
a massive achievement for man to pack that much energy into a pair of
quote: Collisions in the LHC will generate temperatures more than 100 000 times hotter than the heart of the Sun. Physicists hope that under these conditions, the protons and neutrons will 'melt', freeing the quarks from their bonds with the gluons. This should create a state of matter called quark-gluon plasma, which probably existed just after the Big Bang when the Universe was still extremely hot. The ALICE collaboration plans to study the quark-gluon plasma as it expands and cools, observing how it progressively gives rise to the particles that constitute the matter of our Universe today.