CERN: World Record Current in Superconductor

The 20-metre long electrical transmission line containing the two 20 kA MgB2cables. 

Credit: CERN

In the framework of the High-Luminosity LHC project, experts from the CERN Superconductors team recently obtained a world-record current of 20 kA at 24 K in an electrical transmission line consisting of two 20-metre long cables made of magnesium diboride (MgB2) superconductor.

This result makes the technology a viable solution for long-distance power transportation.

"The test is an important step in the development of cold electrical power transmission systems based on the use of MgB2," says Amalia Ballarino, head of the Superconductors and Superconducting Devices section at CERN.

"The cables and associated technologies were designed, developed and tested at CERN."

"The superconducting wire is the result of a long R&D effort that started in 2008 between CERN and the manufacturer, Columbus Superconductors in Genova, Italy."

The result was achieved at a temperature of 24 K (about -249 ˚C) using a test station that was purpose-designed and assembled at CERN.

The temperature is kept homogeneous over the 20-metre length of the line by a forced flow of helium gas.

Following intense development, the full 2 x 20-metre long MgB2 superconducting line was successfully powered to the world-record current of 20 kA, showing that this technology has great potential for the transmission of electrical power.

The superconducting properties of this relatively cheap material were discovered in 2001, but conductor technology only existed in the form of tape.

Round wire, which is more appropriate for assembling into high-current cables, was not available when the CERN project started.

"First, it was necessary to develop quality round wires adapted for use in this project, with high current density and uniform superconducting properties," says Ballarino.

"This work was done through a close collaboration between CERN and Columbus Superconductors, which manufactured different generations of wires with different architectures and with improved properties. In parallel, we at CERN developed the high-current cables and the electrical transmission line."

Jet motorbike: Record breaking Attempt

RICHARD BROWN is a man with unfinished business.

In 1999, he smashed the one-way speed record for a motorbike by hitting 584 kilometres per hour on the salt flats of Bonneville in northern Utah. But his claim on the outright world record - which is based on the average of two runs in opposite directions - was thwarted by technical problems.

Now he is trying again. He hopes to be the first person to exceed 720 km/h on a motorbike while achieving an average two-way speed of at least 640 km/h. Any old bike will not do: he will be using one that is jet-propelled.

While cars used in land-speed-record attempts, like the Bloodhound jet car that will attempt the challenge in 2012, and certain types of boat have taken advantage of jet thrust since the 1950s, all record-breaking motorbikes have used a conventional engine that drives the rear wheel.

This is because it is difficult to pack a jet engine into a two-wheeled frame capable of enormous speed with any degree of safety. Fast cars can be built around old jet fighter engines, but these are far too heavy to fit into a bike that must be balanced by the driver making tiny steering adjustments to the front wheel.

So for his new bike, called Jet Reaction, Brown has redesigned a 930-kilowatt helicopter engine to produce thrust instead of turning a rotor. It was "quite difficult", he says.

"One is working with very fine tolerances in very difficult materials. If you get it wrong, destroying the engine is the most likely result."

Brown has also added his own reheat unit, or afterburner. It sprays fuel into the hot exhaust gases, causing it to ignite and generate yet more thrust. The idea sounds simple enough, though he says that getting it to work at something approaching its theoretical potential "requires much more development". The reheat burner sits above two canisters that deploy braking parachutes when needed.

Brown has a track record in ambitious jet engine projects. Following his 1999 record attempt he built a sub-orbital rocket, but the launch in South Africa had to be cancelled. He is also working on a gas-turbine-powered jet pack, similar to one developed by the US military, that he hopes will allow the wearer to remain airborne for 10 minutes.

Brown's 1999 record attempt involved his own Gillette Mach 3 Challenger bike, which featured a custom-built hybrid rocket engine. The attempt failed because soft ground forced the team to use tyres rather than the usual aluminium wheels. The tyres were only designed to withstand speeds of 380 km/h or so. Eventually the massive centrifugal forces on the rear tyre caused it to deflate.

The current motorbike land-speed record, 606 km/h, was set in 2010 by Rocky Robinson on a bike called the Ack Attack Streamliner. Such record-breakers feature elongated metal bodies - as does Jet Reaction - making them look more like giant bullets than motorcycles. They are also fitted with retractable stabilisers for balance when moving slowly or stationary.

Brown expects to carry out trials with Jet Reaction at a UK airfield in March next year, with an attempt on the world record back at the Bonneville salt flats pencilled in for 2013.

It won't be easy, says Mark Chapman, Bloodhound's chief engineer. "The biggest issue is air intake," he says. "You have to be sure the air flow through the jet is stable or the engine could surge, which could be dangerous."

LHC sets new world record for energy particle accelarator

CERN's Large Hadron Collider has today become the world's highest energy particle accelerator, having accelerated its twin beams of protons to an energy of 1.18 TeV in the early hours of the morning.

This exceeds the previous world record of 0.98 TeV, which had been held by the US Fermi National Accelerator Laboratory's Tevatron collider since 2001. It marks another important milestone on the road to first physics at the LHC in 2010.

"We are still coming to terms with just how smoothly the LHC commissioning is going," said CERN Director General Rolf Heuer. "It is fantastic. However, we are continuing to take it step by step, and there is still a lot to do before we start physics in 2010. I'm keeping my champagne on ice until then."

These developments come just 10 days after the LHC restart, demonstrating the excellent performance of the machine. First beams were injected into the LHC on Friday 20 November.

Over the following days, the machine's operators circulated beams around the ring alternately in one direction and then the other at the injection energy of 450 GeV, gradually increasing the beam lifetime to around 10 hours. On Monday 23 November, two beams circulated together for the first time, and the four big LHC detectors recorded their first collision data.

Last night's achievement brings further confirmation that the LHC is progressing smoothly towards the objective of first physics early in 2010. The world record energy was first broken yesterday evening, when beam 1 was accelerated from 450 GeV, reaching 1050 GeV (1.05 TeV) at 21:28, Sunday 29 November. Three hours later both LHC beams were successfully accelerated to 1.18 TeV, at 00:44, 30 November.

"I was here 20 years ago when we switched on CERN's last major particle accelerator, LEP," said Research and Technology Director Steve Myers. "I thought that was a great machine to operate, but this is something else. What took us days or weeks with LEP, we're doing in hours with the LHC. So far, it all augurs well for a great research program."

Next on the schedule is a concentrated commissioning phase aimed at increasing the beam intensity before delivering good quantities of collision data to the experiments before Christmas. So far, all the LHC commissioning work has been carried out with a low intensity pilot beam. Higher intensity is needed to provide meaningful proton-proton collision rates.

The current commissioning phase aims to make sure that these higher intensities can be safely handled and that stable conditions can be guaranteed for the experiments during collisions. This phase is estimated to take around a week, after which the LHC will be colliding beams for calibration purposes until the end of the year.

Prof John Womersley, Director Science Programmes at STFC said; "this is another fantastic milestone for the LHC. To see such a complex project make progress at this impressive rate is testament to the tremendous efforts that have been made by all of those involved. I look forward to seeing the continued success of the LHC and to early 2010 when we can expect it to deliver the first data for physics analysis".

First physics at the LHC is scheduled for the first quarter of 2010, at a collision energy of 7 TeV (3.5 TeV per beam).