Cern's Large Hadron Collider makes first collisions

By Paul Rincon, Science reporter, BBC News

Engineers operating the Large Hadron Collider (LHC) have smashed together proton beams in the machine for the very first time.

The low-energy collisions came after researchers circulated two beams simultaneously in the LHC's 27km-long tunnel earlier on Monday.

Cern's director of communications, Dr James Gillies, said the first collisions had taken place just as a news conference was under way on Monday to discuss progress following the machine's restart at the weekend.

"We didn't have time to analyse them then. We waited until all four of the (detectors) had seen good candidates (for collisions)," he told BBC News.

The spokesperson for the Alice experiment, Jurgen Schukraft, said cheers erupted with the first collisions.

"This is simply tremendous," he said.

Engineers restarted the LHC on Friday evening after a 14-month hiatus while the machine was being repaired.

It had to be shut down shortly after its inauguration when an electrical fault led to magnets being damaged and to one tonne of liquid helium leaking into the tunnel.

Particle beams injected into LHC for first time since September 2008

Engineers working on the Large Hadron Collider (LHC) have successfully injected beams of particles into two sections of the vast machine.

An LHC spokesperson said this was the first time particle beams had been inside the LHC since it was shut down late in September 2008.

Scientists working on the giant particle accelerator described the success as "a milestone".

They plan to circulate a beam around the 27km-long tunnel in November.

On 23 and 25 October, beams of protons and of lead ions were injected into the LHC ring, and successfully guided both clockwise and anti-clockwise through two of the eight sectors. Each sector is approximately 3.5km long.

The extreme cold allows the magnets inside the LHC, which align and accelerate the beam, to become "superconducting". This means they channel electric current with zero resistance and very little power loss.

The Big Bang, the LHC and the Evolution of the Creation of the Universe by Brian Cox

In "There's probably no God, the Atheists Guide to Christmas" edited by Ariane Sherine, Brian Cox has a chapter on the Big Bang titled "The Large Hadron Collider: A scientific creation story".

The LHC recreates the conditions of the universe less than a billionth of a second after the big bang. The job of the LHC is too study the universe during the time when the Higgs particles are thought to have been generated. The history of the universe is thus:

• 13.7 billion years ago universe begins (t=0)
• gravity separates from the other forces of nature (t+10-43 seconds)
• exponential expansion of universe (t+10-36 s)
• from size of electron to size of melon (t+10-32 s)
• with formation of sub-atomic particles
• and Higgs field (t+10-12 s)
• gives mass to sub-atomic particles
• Higgs acts like cosmic treacle
• if Higgs particles aka Higgs Boson, aka The God Particle (Leon Lederman) exist (after 40 years we don't know) then Higgs Boson must be created in LHC (Standard Model)
• Higgs particles decays too quickly to be seen even in LHC 
• but Muon will be seen from decay of Higgs particle 
• Higgs Boson is tens or hundreds of times heavier than the protons that were smashed together (mini big bang) to create it (E=mc2). Energy=mass
• because Higgs particles are light enough to show up in LHC
• if Higgs particles are NOT found in LHC 
• some other mechanism (Minimally Supersymetric Standard Model?) will show up in LHC which creates mass
• and explains Dark Matter

After t+10-12 s time we already know what happened to the universe because smaller cousins to LHC (eg Fermilab Tevatron?) have been working for decades:-

• 4 forces of nature (strong nuclear, electromagnetic, weak, gravity) formed (t+10-6 s)
• strong nuclear force
• binds quarks together in nucleus of atom
• electromagnetism
• holds electrons in place around nucleus
• weak force
• allows sun to shine, explains radioactive decay
• gravity
• is missing from Standard model
• creates infinities when gravity is added 
• if treat particles as tiny points, when they come infinitely close together, gravity becomes infinitely strong 
• by treating particles as strings (not tiny points) we have a way for gravity to work
• but gravity is included in Einstein's General Relativity
• a Theory of Everything would combine Standard model with General Relativity
• String Theory combines all particles and forces (and makes a decent cup of coffee!)
• quarks and leptons interact
• quarks stick together to give protons & neutrons, neutrinos roam universe (t+1 s)
• protons & neutrons form elements (t+3 minutes)
• Hydrogen 75% : Helium 25% ratio fixed (t+30 m)
• Light as Photons set free from dense universe: cosmic microwave background (t+ 380,000 years)
• gravity collapses H & He to form stars
• 4 forces of nature interact: x3 He fuse to give Carbon
• more fusions give oxygen and other light elements
• stars run out of fuel, explode 
• scattering C & Oxygen & other light elements
• creating Gold, Silver & other heavy elements
• gravity forms stars & dense rocky planets orbit
• on at least one planet, occurs self replication & life & us!

Additional material added above from the 5 YouTube videos:-

This work by crabsallover is licensed under a Creative Commons Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales License.

Talks Brian Cox: What went wrong at the LHC

CERN on YouTube

Final LHC magnet goes underground

A quadrupole magnet in the LHC tunnel

Geneva, 30 April 2009. The 53^rd and final replacement magnet for CERN's Large Hadron Collider (LHC) was lowered into the accelerator's tunnel today, marking the end of repair work above ground following the incident in September last year that brought LHC operations to a halt. Underground, the magnets are being interconnected, and new systems installed to prevent similar incidents happening again.

The LHC is scheduled to restart in the autumn, and to run continuously until sufficient data have been accumulated for the LHC experiments to announce their first results.

"This is an important milestone in the repair process," said CERN's Director for Accelerators and Technology, Steve Myers. "It gets us close to where we were before the incident, and allows us to concentrate our efforts on installing the systems that will ensure a similar incident won't happen again."

The final magnet, a quadrupole designed to focus the beam, was lowered this afternoon and has started its journey to Sector 3-4, scene of the September incident. With all the magnets now underground, work in the tunnel will focus on connecting the magnets together and installing new safety systems, while on the surface, teams will shift their attention to replenishing the LHC's supply of spare magnets.

In total 53 magnets were removed from Sector 3-4. Sixteen that sustained minimal damage were refurbished and put back into the tunnel. The remaining 37 were replaced by spares and will themselves be refurbished to provide spares for the future.

"Now we will split our team into two parts," explained Lucio Rossi, Deputy head of CERN's Technology Department. "The main group will carry out interconnection work in the tunnel while a second will rebuild our stock of spare magnets."

The LHC repair process can be divided into three parts. Firstly, the repair itself, which is nearing completion with the installation of the last magnet today. Secondly, systems are being installed to monitor the LHC closely and ensure that similar incidents to that of last September cannot happen again. This work will continue into the summer. Finally, extra pressure relief valves are being installed to release helium in a safe and controlled manner should there be leaks inside the LHC's cryostat at any time in the machine's projected 15-20 year operational lifetime.

CERN is publishing regular updates on the LHC in its internal Bulletin, available at www.cern.ch/bulletin, as well as via twitter and YouTube at www.twitter.com/cern and www.youtube.com/cern