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LHC Discovers Pentaquark Particles
mrspoonsi sends news that researchers running experiments at the Large Hadron Collider have published findings confirming the existence of pentaquark particles, first predicted in the 1960s by Murray Gell Mann and George Zweig. The particles consist of five quarks bound together. Further research will examine exactly how this binding works.
Previous experiments had measured only the so-called mass distribution where a statistical peak may appear against the background "noise" - the possible signature of a novel particle. But the collider enabled researchers to look at the data from additional perspectives, namely the four angles defined by the different directions of travel taken by particles within LHCb. "We are transforming this problem from a one-dimensional to a five dimensional one... we are able to describe everything that happens in the decay," said Dr. Koppenburg, who first saw a signal begin to emerge in 2012. "There is no way that what we see could be due to something else other than the addition of a new particle that was not observed before."
He's actually referring to this famous Onion article:
http://www.theonion.com/blogpo...
We hope your rules and wisdom choke you / Now we are one in everlasting peace
General Relativity is a shining example of this, and the Standard Model is even more so. These theories are among the most accurate predictors of new discoveries, sometimes ridiculously so.
Meanwhile, String Theory is still kicking around, getting more and more complex, but coming up with very little in the way of prediction. I'm not busting on it... I keep up with the latest work (as much as a non-expert can anyway) and find it fascinating (and/or incomprehensible).
We are definitely tapping into something real, but whether or not it's fundamental is another question entirely. Newton seemed fundamental, but wasn't. Einstein seems fundamental, but might not be. It seems like there's usually another layer of reality below the one which seems to be fundamental. But everything we uncover is fascinating.
I guess what I'm trying to say is, "Science is cool".
You are in a maze of twisty little passages, all alike.
+1.
In detail...
up quark: +2/3
down quark: -1/3
charm quark: +2/3
anti-charm quark: -2/3
2/3 + 2/3 - 1/3 + 2/3 - 2/3 = +1.
If it weren't for deadlines, nothing would be late.
Thanks - so why don't the charm and the anti-charm go "poof" ?
They might not be antiparticles of each other, as they might differ in color charge.
I think that would violate color confinement because the resulting pentaquark would have a net color.
Red up quark, blue down quark, blue charmed quark, green up quark, antiblue anti-charmed quark. Net color = R+B+B+G-B = R+B+G = colorless. (Shamelessly lifted from the "2015 LHCb results" section of the Wikipedia page for the pentaquark.)
You left out, as Paul Harvey says, the rest of the story.
While they planned the route fourteen years ago, they've spent the last nine years (since launch) analyzing the spacecraft's current trajectory and making mid course corrections as needed to ensure that New Horizons hit the window. If they hadn't done so, less than forty minutes after launch New Horizons would have been doomed to miss Pluto entirely. (The booster ended up performing a little 'hot' - when the final stage was discarded, it was actually going too fast.)
Don't get me wrong, it's still a fantastic achievement that all they needed was 20 m/s (give or take a little) of course correction - but the fact remains that New Horizons wasn't passively ballistic, it was actively flown.