LHC is back!

This comes fresh off the press, i.e internal CERN release to personnel:

Geneva, 20 November 2009.
Particle beams are once again circulating in the world's most powerful particle accelerator, CERN*'s Large Hadron Collider (LHC). This news comes after the machine was handed over for operation on Wednesday morning. A clockwise circulating beam was established at ten o'clock this evening. This is an important milestone on the road towards first physics at the LHC, expected in 2010.

"It's great to see beam circulating in the LHC again," said CERN Director General Rolf Heuer. "We've still got some way to go before physics can begin, but with this milestone we're well on the way."

The LHC circulated its first beams on 10 September 2008, but suffered a serious malfunction nine days later. A failure in an electrical connection led to serious damage, and CERN has spent over a year repairing and consolidating the machine to ensure that such an incident cannot happen again.

"The LHC is a far better understood machine than it was a year ago," said CERN's Director for Accelerators, Steve Myers."We've learned from our experience, and engineered the technology that allows us to move on. That's how progress is made."

Recommissioning the LHC began in the summer, and successive milestones have regularly been passed since then. The LHC reached its operating temperature of 1.9 Kelvin, or about -271 Celsius, on 8 October. Particles were injected on 23 October, but not circulated. A beam was steered through three octants of the machine on 7 November, and circulating beams have now been re-established. The next important milestone will be low-energy collisions, expected in about a week from now. These will give the experimental collaborations their first collision data, enabling important calibration work to be carried out. This is significant, since up to now, all the data they have recorded comes from cosmic rays. Ramping the beams to high energy will follow in preparation for collisions at 7 TeV (3.5 TeV per beam) next year.

Particle physics is a global endeavour, and CERN has received support from around the world in getting the LHC up and running again.

"It's been a herculean effort to get to where we are today," said Myers. "I'd like to thank all those who have taken part, from CERN and from our partner institutions around the world."

A press conference will be held at CERN, at the Globe of Science and Innovation, at 2pm on Monday 23 November, and webcast at: webcast.cern.ch...

Great news indeed and quite exciting! I'll be at CERN next week and will report more.

reply to post by buddhasystem

Look out Higgs!

You can run but you can't hide.

Just hope those pesky future particles and the sneaky birds don't attack again. Tempted to say, "Resistance in usless - unless its at least 50K Ohms."

Originally posted by urwatu8
reply to post by buddhasystem

 

Look out Higgs!

You can run but you can't hide.

Just hope those pesky future particles and the sneaky birds don't attack again. Tempted to say, "Resistance in usless - unless its at least 50K Ohms."

Funny you should say that. If memory serves me right, the last year's blowout of LHC magnets was related to residual resistance of 10^-9 Ohm in one of the junctions. The rest was a domino effect due to serial explosions of the magnets.

First "beam splash events" have been recorded:

atlas.web.cern.ch...

History is being made.

Another event:

files.abovetopsecret.com...

Yay! They finally got it online!
I really hope everything goes alright this time...

Got the news from this source: Engadget

Fresh news:

LHC's twitter

Fresh press-release from CERN:

Geneva, 23 November 2009. Today the LHC circulated two beams simultaneously for the first time, allowing the operators to test the synchronization of the beams and giving the experiments their first chance to look for proton-proton collisions. With just one bunch of particles circulating in each direction, the beams can be made to cross in up to two places in the ring. From early in the afternoon, the beams were made to cross at points 1 and 5, home to the ATLAS and CMS detectors, both of which were on the lookout for collisions. Later, beams crossed at points 2 and 8, ALICE and LHCb.

“It’s a great achievement to have come this far in so short a time,” said CERN Director General Rolf Heuer. “But we need to keep a sense of perspective – there’s still much to do before we can start the LHC physics programme.”

Beams were first tuned to produce collisions in the ATLAS detector, which recorded its first candidate for collisions at 14:22 this afternoon. Later, the beams were optimised for CMS. In the evening, ALICE had the first optimisation, followed by LHCb.

First public images of collisions, recorded by Atlas experiment, have just become available here.