The physics story of the moment is probably the detection of single top quarks at Fermilab. Top quarks, like most other exotic particles, are usually produced in particle-antiparticle pairs, with some fraction of the kinetic energy of two colliding particles being converted into the mass of the quark-antiquark pair (see this old post). There's a very rare process, though, mediated by the weak nuclear force, that allows the production of a single top quark, without an anti-top (it's paired with a bottom quark and a W boson).
The D0 (or DZero) collaboration at Fermilab recently announced the observation of single top quarks in their data, and links abound. There's a press release here, Gordon Watts provides the view from inside the collaboration, as well as links to talk slides about the result. Tommaso Dorigo of the CDF collaboration (who are also looking for single tops at Fermilab) has his own report, as well as an explanation of the process.
And if you're wondering how they detect all this stuff, JoAnne Hewett explains detectors (or you could check out this old post).
It's also worth noting exactly what particle physicists mean when they describe a process as "rare"-- D0 is reporting the detection of sixty-odd single top quarks. That's out of a dataset derived from trillions of particle collisions. That's trillions, with a "tr," the sort of number you usually only see in discussions of planetary GNP. That's pretty damn impressive.
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Don't you mean national economic measures? Isn't the US economy of something like 12 trillion dollars in size alone? (Not to mention the national debt...)
By the way, off-topic but also interesting: apparently today is the centenary of the publication of Planck's paper.
Don't you mean national economic measures? Isn't the US economy of something like 12 trillion dollars in size alone? (Not to mention the national debt...)
Yeah, but they're talking about hundreds of trillions of events...
By the way, off-topic but also interesting: apparently today is the centenary of the publication of Planck's paper.
Well, the centehexenary, or whatever the word for "106 years ago" would be. Still, pretty cool.
Ah. An order of magnitude. Thanks for the detail.
Is that even a word? If not, I think you get to make a resoundingly successful company out of it =).
the press release is poorly worded.
Presumably the top quark was not naked and single, but was part of some integer electric charge combination of other quarks and anti-quarks, and what they saw was a t-quark bound to other quarks, as opposed to a t-\bar t combo?
It was better in Carl Anderson's day, when you could win a Nobel Prize by flying a lump of emulsion and a magnet in a balloon. Or Robert A. Millikan's day, spraying oil droplets. Oh, wait... except for the number of coauthors, postdocs, PhD dissertations, and subcontractors in the experiment. Never mind...
Ah, to my chagrin I neither heard the broadcast correctly, nor read the transcipt closely enough. 1900 indeed. Where is my mind these days? (I personally blame all the Shiner, but that's a whole nother saga you don't want to hear...)
Hi Chad,
thanks for the link... By the way, I like the title of this post, and I think it could have been even nicer if instead than "no freaks" you had put "no strings attached"... ;) The reference to color strings of gluons emitted preferentially in pair production and suppressed in EW production of single top being subtle...
Cheers,
T.