Piece of crusty bread paralyzes a cooling unit.
“Nobody knows how it got there,” she told The Times. “The best guess
is that it was dropped by a bird, either that or it was thrown out of
a passing aeroplane.”
One does wonder how an installation that is supposed to be enclosed
with a 31 kilometer tunnel would have had access for either a bird or
the miracle toss from an airplane.
From Times Online
November 5, 2009
Large Hadron Collider stalled again... thanks to chunk of baguette
A baguette
A spokesman for CERN told The Times: 'Nobody knows how it got there.
The best guess is that it was dropped by a bird, either that or it was
thrown out of a passing aeroplane'
Nico Hines
The rehabilitation of the beleaguered Large Hadron Collider was on
hold tonight after the failure of one of its powerful cooling units
caused by an errant chunk of baguette.
The £4 billion particle-collider faced more than a year of delays
after a helium leak stymied the project in its first few days of
operation. It is gradually being switched back on over the coming
months but suffered a new setback on Tuesday morning.
Scientists at the CERN particle physics laboratory in Geneva noticed
that the system’s carefully monitored temperatures were creeping up.
Further investigation into the failure of a cryogenic cooling plant
revealed an unusual impediment. A piece of crusty bread had paralysed
a high voltage installation that should have been powering the cooling
unit.
The cooling systems are in place to keeps the collider functioning at
a temperature of 1.9 degrees above absolute zero. As soon as there is
a small rise in temperature the super-conducting magnets stop
functioning and fail safes come into operation to control the
collider.
A spokeswoman for CERN confirmed that baguette was responsible for the
latest hiatus, but she conceded that mystery surrounded the way it got
into the vital power installation, which is protected by high security
fences.
“Nobody knows how it got there,” she told The Times. “The best guess
is that it was dropped by a bird, either that or it was thrown out of
a passing aeroplane.”
“Obviously this was slightly surprising. Within the team there was
some amusement once they had relaxed after initial concerns.”
The bread was discovered on a busbar - an electrical connection inside
one of eight buildings above ground on the 17-mile (27km) circuit in
the Swiss countryside.
The spokeswoman said: “The collider extends over a very large area –
you have to have a very comprehensive system to try to avoid problems
of this kind. We’re talking about a couple of days down time.”
Scientists hope that the temperature will be restored by around
midnight tonight allowing work to continue. The failure of the cooler
meant the temperature rose around 5 degrees to the equivalent of about
-266C.
The first beams were injected into the LHC on September 10 last year,
but nine days later a connection between two magnets failed. This
caused a huge leak of the helium that cools the ring around which
protons will be fired against one another at 99.9999991 per cent of
the speed of light.
The leak inflicted further damage, and the accelerator was mothballed
so that 53 magnets could be replaced. Engineers have since found and
replaced other magnet connections that could have been at risk of
causing a repeat of the fault, and installed other safety features to
prevent another fault.
http://www.timesonline.co.uk/tol/news/science/physics/article6905250.ece
|
