"Cascade B" Particle Discovered At Fermilab

pnotequalsnp writes to note that physicists at Fermilab have discovered a new heavy particle called the Cascade B. This is the first particle ever seen that is made up of quarks representing all three quark families. A team of 610 physicists from 88 institutions reported the discovery in a paper submitted to Physical Review Letters last week. This must be the discovery that triggered rumors that the Higgs had been found.

Comments

To quote "Napolean Dynamite"...

[TheDarkener]

"I don't understand a word you just said."

Re:What's the significance?

[zahl2]

http://dorigo.wordpress.com/2007/06/10/cascade-b-b aryons-in-the-bag/

...it is a very nice new bit of evidence that our understanding of heavy hadrons (particles composed of quarks, one of which a b or a c) is very accurate. The particles, yielding a signal whose significance exceeds seven standard deviations, have a mass in perfect agreement with theoretical expectations.

http://www.pegasusnews.com/news/2007/jun/14/uta-fe rmilab-physicists-discover-triple-scoop-bary/

Its discovery and the measurement of its mass provide new understanding of how the strong nuclear force acts upon quarks, the basic building blocks of matter.

"Knowing the mass of the cascade b baryon gives scientists information they need in order to develop accurate models of how individual quarks are bound together into larger particles such as protons and neutrons," said Physicist and Associate Director for High Energy Physics for the Department of Energy's Office of Science Robin Staffin.

So, yeah, Standard Model stuff. Practical? Well:

http://motls.blogspot.com/2007/06/d0-discovers-cas cade-b.html

Shows that YES! Building particle detectors involves a large waterpark a la Waterworld. You can make money off of that, therefore, it must be practical. (Seriously, is my browser showing this wrong? I see no indication that this guy is joking?)

Not related to Higgs boson

[hweimer]

This is completely unrelated to the search for the Higgs boson. While the Higgs is believed to be the elementary particle responsible for giving mass to all other particles, the Xi_b mentioned here is a composite particle consisting of three previously known quarks. So while it is good to know that the particle really exists as predicted by the standard model, this is definitely not the Nobel prize physics the discovery of the Higgs would be.

not the higgs

[kakapo]

This particle is not related to the rumored detection of the Higgs. It is 30 times lighter than the unexplained resonance that is at the basis of these rumors.

Re:Unlikely to match the Higgs rumors...

[jpflip]

Fair enough - it was late and I threw in a bit of jargon there :) A bit of explanation:

(1) 1 GeV is approximately the proton mass, so this new particle is a bit over 5x the proton mass

(2) "Resonance" in this case means a feature in their data that looks like a new particle. When analyzing data from an accelerator, you basically add up the energies of all the particles coming out of a collision and histogram the result for a lot of collisions. If you see a peak in the histogram, it may mean that something interesting is happening at collisions of a particular energy, and such a peak is a signature that a particle is being created. The rumors related to a peak at ~180 GeV, which means it probably isn't the same peak that led to the discovery of the 5 GeV "cascade B" mentioned in this article.

(3) Dzero (or D0) is one of the two major detectors at the Tevatron particle accelerator (the other is CDF). They are the source of the rumors and of this new discovery.

(4) I say this is probably an "analysis issue", in that the 180 GeV feature could turn out to be an analysis mistake. It's probably being rechecked extensively by the folks working on Dzero, and they'll eventually let us know if it's real.