Interactions News Wire #06-09
9 February 2009
http://www.interactions.org
*******************************************
Source: CERN
Content: Press Release
Date Issued: 9 February 2009
*******************************************
CERN management confirms new LHC restart schedule
Geneva, 9 February 2009. CERN* management today confirmed the restart
schedule for the Large Hadron Collider (LHC) resulting from the
recommendations from last week's Chamonix workshop. The new schedule
foresees first beams in the LHC at the end of September this year, with
collisions following in late October. A short technical stop has also
been foreseen over the Christmas period. The LHC will then run through to
autumn next year, ensuring that the experiments have adequate data to
carry out their first new physics analyses and have results to announce in
2010. The new schedule also permits the possible collisions of lead ions
in 2010.
In Chamonix there was consensus among all the technical specialists that
the new schedule is tight but realistic.
"The schedule we have now is without a doubt the best for the LHC and for
the physicists waiting for data," said CERN Director General Rolf Heuer.
"It is cautious, ensuring that all the necessary work is done on the LHC
before we start-up, yet it allows physics research to begin this year."
This new schedule represents a delay of six weeks with respect to the
previous schedule, which foresaw the LHC "cold at the beginning of July".
The cause of this delay is due to several factors such as implementation
of a new enhanced protection system for the busbar and magnet splices;
installation of new pressure-relief valves to reduce the collateral damage
in case of a repeat incident; application of more stringent safety
constraints; and scheduling constraints associated with helium transfer
and storage.
The enhanced protection system measures the electrical resistance in the
cable joints (splices) and is much more sensitive than the system existing
on 19 September.
The new pressure relief system has been designed in two phases. The first
phase involves installation of relief valves on existing vacuum ports in
the whole ring. Calculations have shown that in an incident similar to
that of 19 September, the collateral damage would be minor with this first
phase. The second phase involves adding additional relief valves on all
the dipole magnets and would guarantee minor collateral damage (to the
interconnects and super-insulation) in all worst cases over the life of
the LHC.
The management has decided for 2009 to install the additional relief
valves on four of the LHC's eight sectors, at the same time as repairs in
the sector damaged last September and other consolidation work already
foreseen. The dipoles in the remaining four sectors will be equipped in
2010.
Contact information:
James.Gillies@cern.ch
+ 41 22 767 4101
* CERN, the European Organization for Nuclear Research, is the world's
leading laboratory for particle physics. It has its headquarters in
Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the
Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy,
Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden,
Switzerland and the United Kingdom. India, Israel, Japan, the Russian
Federation, the United States of America, Turkey, the European Commission
and UNESCO have Observer status.
