Fermilab statement on
magnet test failure

An inner-triplet quadrupole during installation in June 2006.

On Tuesday, March 27, there was a serious failure in a high-pressure test at CERN of a Fermilab-built "inner-triplet" series of three quadrupole magnets in the tunnel of the Large Hadron Collider. The magnets focus the particle beams prior to collision at each of four interaction points around the accelerator.

Safety precautions were followed during the test, and no one was injured.

A full investigation of the failure is underway, but preliminary indications are that structures supporting the inner "cold mass" of one of the three magnets within its enclosing cryostat broke at a pressure of 20 atmospheres, in response to asymmetric forces applied during the test. Such forces are expected on occasion during normal operation of the LHC. The failure does not concern the magnets or the cold masses themselves, but rather their assembly in the cryostat.

While the full cause of the problem is not yet known, failure to account for the asymmetric loads in the engineering design of the magnet appears to be a likely cause. The test configuration corresponds to conditions that occur during a magnet quench, when a superconducting magnet suddenly "goes normal," releasing large amounts of energy. They may also occur during magnet cooldown and during certain other conditions such as refrigerator failure. From 1998 to 2002, Fermilab conducted four engineering reviews of the magnets by experts from Fermilab, other US national laboratories and CERN. The reviews do not appear to have addressed these asymmetric loads. Tests at Fermilab were done on single magnets where such loads do not develop.

At this point the consequences, if any, for the LHC schedule are not yet known.

Read more

Captured in Ice

Sky map from the AMANDA neutrino telescope showing the 1,112 atmospheric neutrino candidates observed. Scale reflects excess or deficit from mean background events. Image courtesy of Andrea Silvestri, AMANDA, UCI

As scientists explore the most violent phenomena in the universe, the tiny, almost massless particles called neutrinos are valuable messengers, traveling unimpeded across the vast distances of space.

"By analyzing neutrino data on the TeraGrid we've been able to validate a new kind of 'telescope' that gives a dramatic new view of the universe through the window of high-energy neutrinos," says University of California at Irvine astrophysicist Andrea Silvestri. "This can help scientists unravel a number of longstanding mysteries about the origin and apparent surplus of the highest-energy cosmic rays."

Read More

Wednesday's story on the attempted theft of scrap metal incorrectly described the container involved as a dumpster, instead of as a recycling area. Fermilab Today regrets the error.

The Arizona Republic
March 28, 2007:

Giant telescope a point of pride

Device a big step for science in Mexico, world

SIERRA NEGRA, Mexico - It looms over Mexico from a mountain so high it's hard to breathe, a massive white radio telescope of monumental proportions.

Its dish is half the width of a football field, stands as high as a 20-story building and watches the sky from a mountain taller than any peak in the contiguous United States.

The Large Millimeter Telescope is the most ambitious scientific project Mexico has ever undertaken, the government says. It also is part of a growing trend, as U.S. and European astronomers search the world for higher, drier sites where they can collect more of the faint signals from space.

Read More