Back-to-Back b Baryons

Using the Tevatron collider, DZero found 19 cascade b baryons, while the CDF experiment had 17.

Scientists at Fermilab have announced the observation of the cascade b baryon—again.

In a paper submitted for publication to Physical Review Letters on June 12, scientists of Fermilab's DZero experiment announced their discovery of the "triple scoop" baryon, which contains one quark from each generation of matter.

Then, on June 15, scientists from Fermilab's CDF experiment announced their own independent cascade b observation.

Read the press release

ATLAS Toroid lowered into cavern at CERN

The first Toroid End Cap magnet just before it was placed in the ATLAS cavern. (Click on image for larger version.)

What do you get when you cross a 260-ton magnet with an experienced and talented assembly team at CERN? The successful installation of the first Toroid End Cap magnet for the ATLAS detector, which was completed early last week.

This 12-meter tall component complements the barrel toroid magnet, one of the largest magnets ever built. The size is necessary to produce magnetic fields tens of meters across within the ATLAS detector. Such fields are critical in measuring muons, the longest lasting of the unstable elementary particles.

In addition to being very large, the toroid end-cap magnets are also very delicate, containing eight super conducting magnetic coils.

"It was one of the most difficult objects we have had to lower into the cavern," said ATLAS project engineer Mark Hatch.

Using the 280-ton overhead crane---not the most agile of machines---the team at CERN carefully lowered the End Cap 240 feet into the ATLAS cavern. They then fit it into place within the Barrel Toroid, the main piece of magnetic hardware, without damaging any of the experiments many sensitive components.

Teams from SLAC have been involved with the ATLAS experiment for the past 11 months. Projects include work on the pixel detector, the trigger, and the commissioning of studies. (Click here to read a related SLAC Today story.)

-- Ken Kingery, SLAC

From New York Times Sunday Book Review, June 24, 2007

Meta Physicists

As though their knowledge of the quantum secrets came with the power of prophecy, some three dozen of Europe's best physicists ended their 1932 meeting in Copenhagen with a parody of Goethe's "Faust." Just weeks earlier, James Chadwick had discovered neutrons - the bullets of nuclear fission - and before long Enrico Fermi was shooting them at uranium atoms. By the time of the first nuclear explosion a little more than a decade later in New Mexico, the idea of physics as a Faustian bargain was to its makers already a cliché. Robert Oppenheimer, looking for a sound bite, quoted Vishnu instead: "Now I am become Death, the destroyer of worlds."

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