Single and loving it!

Left to right: Cecilia Gerber, of the University of Illinois at Chicago, presented the DZero result and Rainer Wallny, of UCLA, showed CDF's result

Single physicist searching for single red, blue or green, top quark for fun and possible long term relationship. Must like high speeds and live life fast. I'll be waiting for you in the control room of a large Fermilab particle detector.

Fourteen years ago this month, the DZero and CDF experiments jointly announced the discovery of top quarks. In those observations, top quarks were always produced in pairs. A quark and antiquark from the proton and antiprotons in the beam annihilated into a gluon that then became a top quark and an antimatter top quark. By capturing just a couple of dozen collisions in which these quarks were made, scientists were able to definitively say top quarks existed.

Pairs of top quarks are relatively easy to see since they have a distinct signature, but it has long been assumed that it is also possible to create collisions producing a single top quark. As an example, in these types of collisions, a quark and antimatter quark from the beams combine and create the weak-force carrying W boson. This W boson then decays into a top quark and a bottom antimatter quark. Because the W boson only has half the mass of a top quark, this kind of event could not occur without the principles of quantum mechanics. The W boson in these events briefly has about double the regular mass, allowing the reaction to proceed.

Physicists have been combing the data from billions of collisions for years, looking for events in which single top quarks have been made. Even though the Tevatron produces about the same amount of top quark pairs as single tops, these events are trickier to isolate. The false positive rate is much higher. It’s much harder to mistakenly find two top quarks than just one.

However DZero and CDF jointly presented yesterday to a packed house at Fermilab their newest results: a discovery of the single top quark .A celebration in the Fermilab User’s Center followed the presentation. Yet another piece of the Standard Model puzzle has clicked neatly into place.

Single and loving it ...

-- Don Lincoln and Craig Group

The evidence for the single top quark production was shown at Fermilab at a special seminar to a standing-room only crowd.

Congress Sends $410 Billion Spending Bill to Obama for Signing

From Bloomberg, March 11, 2009

The U.S. Congress gave final approval to a $410 billion bill that will boost domestic spending, loosen the trade embargo on Cuba and fund thousands of congressional pet projects known as earmarks.

The Senate, after a delay last week that highlighted Democrats' tenuous grip on the chamber, approved the so-called omnibus bill on a voice vote yesterday. Moments earlier, the bill cleared a key procedural vote, 62 to 35. The legislation, which the House passed Feb. 25, heads to President Barack Obama for his signature into law.

Democrats said the bill would provide needed funding increases for federal agencies that saw too many lean years during former President George W. Bush's administration.

"The agencies of our government have been so under-funded and under-resourced during the Bush years that these agencies need this money so they can function properly," said Senate Majority Leader Harry Reid, a Nevada Democrat.

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Indian Association of Fermilab presents Dandia/Garba dance event March 27

The Indian Association of Fermilab, Drishiti, will host a celebration in honor of the Indian Holi festival with dancing done in two styles: Dandia and Garba. The open celebration takes place from 4 to 6:30 p.m. on Friday, March 28, in Kuhn Barn in the Fermilab Village.

These dances feature circular movements timed to the clapping of hands or jingling of sticks along with the sounds of various musical instruments.

Garba, a popular folk dance, is a unique group dance where people dressed in colorful dresses move gracefully in a circle. Dandia, a light-spirited dance, is performed with decorated bamboo sticks called dandies held in the hands. Drishiti will provide Dandia sticks for the dance, and will offer free lessons for newcomers.

View a demonstration of Dandia here.

A potluck dinner will follow the dance. Please bring your favorite dish to share. Tickets are $5 per person, and reservations are required. Please RSVP by March 16 to Fermilab.Drishti@gmail.com.