Geneva, 30 April 2009-Final LHC magnet goes underground

Final LHC magnet goes underground

Geneva, 30 April 2009. The 53^rd and final replacement magnet for CERN's¹ 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

1. 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.

Cern 16 April 2009 The last repaired dipole for Sector 3-4 has been lowered into the LHC tunnel.

The Latest from the LHC
The last repaired dipole for Sector 3-4 has been lowered into the LHC tunnel.

© CERN

Watch the video Here !

Δες το Βίντεο Εδώ !


The 39th and final repaired dipole magnet was lowered into Sector 3-4 and installed on Thursday 16 April. This is the last of the LHC’s easily recognizable 15-metre-long blue superconducting dipoles required for the 3-4 repair. Only two more Short Straight Sections (SSS) remain to be installed in 3-4.

Since the start of the repair work in Sector 3-4, the Vacuum Group have been cleaning the beam pipes to remove metallic debris and soot created by the short circuit last September. Firstly all 4800 m of the beam pipes in Sector 3-4 were surveyed cm by cm to document the damage before the cleaning work started. The cleaning process involves passing a brush through the pipe to clean the surface mechanically, followed by a vacuum to remove any debris both inside and outside the beam pipe. This procedure is repeated ten times, followed by a final check with an endoscopic camera. So far 68% has been completed.

Work to install the new pressure release ports has now started in the areas outside the arc sections – in particular on the inner triplets (the focusing magnets either side of the collision point). The ports have been slightly modified to fit the geometry of these magnets.

A new test has been developed to measure the electrical resistance of the connection joining the ‘busbars’ of the superconducting magnets together. The busbar consists of a superconducting cable surrounded by a larger copper block known as a ‘stabilizer’. The copper helps to conduct electricity in the event that part of the superconducting cable becomes normally-conducting (for example during a quench). The new test allows the electrical continuity of this copper part to be checked. This provides another important quality control safety check for the electrical connections.

Cern 24 April 2009-T2K neutrino beam starts operation

News: 24 April 2009

T2K neutrino beam starts operation

The Tokai to Kamioka (T2K) neutrino oscillation experiment confirmed the first neutrino beam yesterday. The team verified the neutrino beam by observing the muons produced by the proton beam in the neutrino facility at the Japan Proton Accelerator Complex (J-PARC).

The T2K project, which is a CERN recognized experiment, involves sending a neutrino beam from J-PARC at Tokai to the Super-Kamiokande neutrino observatory some 300 km away. In a similar manner to the neutrino beam sent from CERN to experiments in Gran Sasso (Italy), the T2K experiment hopes to increase our understanding of neutrino mass by looking at oscillations between different types of neutrinos.

In 2005 CERN donated a magnet originally built for the UA1 detector to the Japanese High Energy Accelerator Research Organization (KEK) for use in the T2K experiment. More details available here.

Read the full KEK press release here:
http://www.kek.jp/intra-e/press/2009/J-PARCT2K.html

Cern 23 April 2009-First beam in the SPS after the winter shut-down

News: 23 April 2009

First beam in the SPS after the winter shut-down

The first beam was injected today from PS into SPS. After some earlier repairs to the ejection and injection components the teams managed to get first beam exactly on schedule.

Cern 6 April 2009-PS has beam ahead of schedule

Ανακοινώθηκε με χαρά!!!





The Latest from the LHC

The campaign to install the new helium pressure release system is progressing well. The first sector to be fully completed is 5-6, with all 168 individual pressure release ports installed. These ports will allow a greater rate of helium escape in the event of a sudden increase in pressure of the insulation vacuum. To install them the teams had to initially open the ‘W bellows’ – the large accordion-shaped sleeves that cover the interconnections between two magnets. Now that all the pressure release ports have been fitted, these ‘W bellows’ can start to be closed up again – marking the end of the consolidation work in 5-6. Preparations are starting to be made to cool the sector down: this week the first three ‘vacuum sub-sectors’ have been sealed. Each sub-sector is a 200 metre-long section of the insulating vacuum chamber that surrounds the magnet cold mass. Once sealed the sub-sector is pumped out and tested for leaks.

The damaged area of Sector 3-4 is buzzing with activity. Teams are working through the night and on weekends to install the replacement magnets at a rate of 6-7 per week. With more and more magnets installed and aligned, the pace of the work to join all the various connections from each magnet to its neighbours, has increased sharply over the past few weeks: for example, the soldering of electrical joints has gone up from 2 to 8 interconnects per week within a fortnight.

Work to fit the replacement magnet in Sector 1-2 has been completed. This magnet replaces one that was found to have high internal resistance and was previously removed (see previous update - http://cdsweb.cern.ch/record/1158758?ln=en).

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News: 6 April 2009
PS has beam ahead of schedule

Protons are circulating again in the PS after the winter shut-down: Saturday morning at 2:14, a few days ahead on the official schedule, the PS received its first beam of protons of the year just a few days after the LINAC 2 and the PS Booster.

After having been partially refurbished, the injector chain is performing well and the non-LHC physics programme is progressively restarting. The next in the chain is the SPS, expected to re-start in the week after Easter.

* View the 2009 Injector Accelerator Schedule on the BE department website (PDF format)


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Το Άγιο Φως..Ένα Πραγματικό θαύμα

Πραγματικά ένα βίντεο το οποίο πρέπει να το δουν όλοι οι Χριστιανοί του κόσμου..
Τα λόγια εδώ δεν μπορούν παρά να σβήσουν σαν την αμαρτία μπροστά στον θεό.

...Δείτε το μεγαλείο του θεού μας...

Μακάρι κάθε Χριστιανός να είχε αυτήν την εμπειρία..