June 27, 2005


In quark world, a strange discovery (Byron Spice, June 27, 2005, Pittsburgh Post-Gazette)

Like a grocery shopper peering at a jar of spaghetti sauce in search of flecks of basil, physicists have taken a long look at the proton and have found an extra, if long-suspected, ingredient inside.

Physicists know that the positively charged protons in atomic nuclei are made primarily of two types of elementary particles, the so-called up and down quarks. But now an experiment called G-Zero at Jefferson Lab in Newport News, Va., has confirmed the presence of a third type, or "flavor" of quark, the strange quark.

To find that protons contain strange quarks isn't a major surprise, said Brian Quinn, a Carnegie Mellon University physicist who is part of the international G-Zero collaboration. But what was somewhat startling was the degree to which strange quarks actually affect the structure and behavior of the proton, he added.

"We're showing that they could be a significant part of what makes up the proton," agreed Gregg Franklin, another Carnegie Mellon physicist among the 108 scientists on the G-Zero team.

Gotta admire the faith of folks who can miss an entire quark but still convince themselves the quark is indivisible.

Posted by Orrin Judd at June 27, 2005 12:00 AM

There are four types of quarks..

Up, Down, Strange, and Charmed...

Posted by: Bartman at June 27, 2005 8:36 AM

...and richardbenjamin

Posted by: oj at June 27, 2005 9:00 AM


Actually, there are six known quarks, the four you list plus the "top" and "bottom" quark (originally "truth" and "beauty" but that was too cute even for particle physicists).

Mr. Judd;

The strange quark has been known about for decades. Its presence in the proton is not as a constituent part but part of the vacuum fluctuation, so it hardly counts as a "miss".

Posted by: Annoying Old Guy at June 27, 2005 10:59 AM

Wow? decades? We really are at the ends of knowledge now....

Posted by: oj at June 27, 2005 11:07 AM

Gotta love the experiment description: "Rather than bust the nuclei apart, the electron beam dislodged some nuclei, sending them careening away from the target. By detecting these scattered protons and applying some "mathematical trickery," the researchers were able to discern the presence of the strange quark ...." Mathematical Trickery, indeed!

Posted by: jd watson at June 27, 2005 1:42 PM


That's why so much is "long suspected" rather than "known".

Posted by: Annoying Old Guy at June 27, 2005 4:12 PM

"That's why so much is 'long suspected' rather than 'known'."

. . . ..

The scientists' disciplined nature that leads to a distinct reduction in BS ... demonstrates what you, oj, are clearly lacking.

OK, guys, resume this humanities-oriented farce.

Posted by: LarryH at June 28, 2005 7:00 PM

If you start with BS, all the discipline in the world won't allow you to finish with other than BS.

Posted by: oj at June 28, 2005 7:53 PM

I once read a article in a physics journal with the title "New subatomic particles or why I believe in quarks." My reaction was "Every time a physicist says 'I don't believe in quarks,' somewhere a quark dies."

Posted by: Joseph Hertzlinger at June 30, 2005 12:04 AM