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More Faults Found in LHC, But No Further Delay to Start-up

The LHC repairs are progressing well (CERN)

In September 2008, the Large Hadron Collider (LHC) suffered a catastrophic quench, triggered by a faulty connection in the electronics connecting two of the supercooled magnets between Sections 3 and 4 of the 27 km-circumference particle accelerator. The "S34-incident" caused tonnes of helium coolant to explosively leak into the LHC tunnel, ripping the heavy electromagnets from their concrete mounts.

Naturally, this was a huge blow for CERN, delaying the first particle collisions by several months. However, the repair work is progressing well, and hopes are high for commencement of LHC science as early as this summer. Now engineers are working hard to avoid a recurrence of the S34 Incident, tracking down similar electrical faults between the accelerator magnets. It seems like they have found many more faults than expected…

According to a recently published progress report, the LHC repairs are progressing as planned, but more electrical faults have been discovered in other sections of the accelerator. An electrical short has been blamed for the quench four months ago, only weeks after the first circulation of protons around the LHC in the beginning of September 2008. It is now of paramount importance to isolate any further potential shorts in the complex experiment. It would appear engineers are doing a good job in tracking them down.

Ribbons of superconducting niobium-titanium wire is used by the LHC to carry thousands of amps of current to the magnets. Connecting the ribbon from electromagnet-to-electromagnet are splices that are soldered in place. Should one of these splices be weakened by poor soldering, an electrical short can occur, making the magnets lose superconductivity, initiating a quench, rapidly heating the sensitive equipment. Various sections are being re-examined and re-soldered. The good news is that this additional work is not compounding the delay any further.

It has been confirmed that there was a lack of solder on the splice joint. Each sector has more than 2500 splices and a single defective splice can now be identified in situ when the sector is cold. Using this method another magnet showing a similar defect has been identified in sector 6-7. This sector will be warmed and the magnet removed. The warm up of this additional sector can be performed in the shadow of the repair to sector 3-4 and will therefore not add any additional delay to the restart schedule. — CERN

Hopefully we'll see a second circulation of protons this summer, and according to informal rumours from a contact involved in the LHC science, the first particle collisions could start as early as October 2009. I will listen out for any further official confirmation of this information…

Sources: CERN, Nature.com

Source: http://www.universetoday.com/2009/02/02/more-faults-found-in-lhc-but-no-further-delay-to-start-up/

Waiting for the Higgs Boson

Elizabeth Kolbert on the Large Hadron Collider :

To theorists, the tantalizing promise of the L.H.C. is that it will, finally, supply the evidence of “new physics” that they’ve been waiting for. Certain patterns of missing energy, for example, would suggest the existence of extra dimensions, as would the creation of mini black holes. Different results—also in the form of missing energy—would indicate the existence of squarks or other superparticles. There are good theoretical reasons to expect these phenomena to begin to appear at the energy level of the L.H.C., or so at least Arkani-Hamed tried to explain to me over several more espressos. He told me that he was completely confident the Higgs would be found at the collider: “I would bet many, many months’ salary.” He also said that if the Higgs was the only result, the L.H.C. would be a disappointment. “We theorists, we’re a hard lot to please. We’ve taken things for granted for so long we say, ‘Oh, yeah, for sure you’ll discover the Higgs.’ But the things we’re really interested in are all these major puzzles.”

Brian Greene talks about the promise offered by LHC in finding the Higgs Boson:

where does mass itself come from?

More than 40 years ago, a number of researchers, including Peter Higgs, an English physicist, suggested an answer: perhaps space is pervaded by a field, much like the electromagnetic fields generated by cellphones and radio broadcasts, that acts like invisible molasses.

When we push something in the effort to make it move faster, the Higgs molasses would exert a drag force — and it’s this resistance, as the Higgs theory goes, that we commonly call the object’s mass. Scientists have incorporated this idea as a centerpiece of the so-called standard model — a refined mathematical edifice, viewed by many as the crowning achievement of particle physics, that since the 1970s has described the behavior of nature’s basic constituents with unprecedented accuracy.

The one component of the standard model that remains stubbornly unconfirmed is the very notion of the Higgs’ “molasses” field. However, collisions at the Large Hadron Collider should be able to chip off little chunks of the ubiquitous Higgs field (if it exists), creating what are known as Higgs bosons or Higgs particles. If these particles are found, the standard model, more than a quarter-century after its articulation, will finally be complete.

It’s totally irrelevant, but I enjoyed the bad web design of the LHC site. Compare to NASA and Fermilab.

Martin Schmaltz writes another introduction. Steven Hawking bets that people won’t find the Higgs boson, and that would make physics even more interesting.

I get all gushy about big science, if only because it is completely beyond my comprehension. As I look through Wikipedia, it’s clear to me how often theoretical possibilities inspire great science fiction. (See also this). By the way, currently, LHC is down for repairs; expected to come online again in July 2009. Wikipedia says it might take up to 3 years to gather enough data to prove or disprove the existence of the Higgs boson.

Joel Aschenbach defends basic science projects like LHC:

Some U.S. money has gone into the LHC, which will cost billions of dollars: five, maybe ten—the exact number is elusive (the science will be precise, but the accounting apparently follows the Uncertainty Principle). But most of the engineering is being done by European firms. Jürgen Schukraft, who supervises an LHC experiment named ALICE (which will re-create conditions the same as those just after the big bang), said, "The brain drain that used to go from Europe to the States definitely has reversed."

The cynic might say that there’s no practical use for any of this, that there might be other uses for all the money and brainpower going into these particle guns. But we live in a civilization shaped by physics. We know that the forces within an atom are so powerful that, unleashed and directed against humanity, they can obliterate cities in an instant. The laptop computer on which I’m writing uses microprocessors that would not exist had we not discovered quantum physics and the quirky behavior of electrons. This story will be posted on the World Wide Web—invented, in case you hadn’t heard, at CERN, by computer scientist Tim Berners-Lee. Maybe you’re reading it while listening to your iPod, which wouldn’t exist but for something called "giant magnetoresistance." Two physicists discovered it independently in the late 1980s, with not much thought of how it might eventually be used. It became crucial to making tiny consumer electronics that used magnetized hard disks. The physicists won a Nobel Prize in 2007, and you got a nifty sound system that’s smaller than a Hershey bar.

Source: http://www.imaginaryplanet.net/weblogs/idiotprogrammer/?p=83400287

CPH Stands of: Creative Particle of Higgs that

propounded by Hossein Javadi in 1987 Biography