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New 'Mystery Meson' Sub-Atomic Particle Discovered
securitas writes "The BBC reports that scientists in Japan have discovered a new sub-atomic particle that defies current theories of matter and energy. The 'mystery meson' X(3872) was revealed while studying beauty quarks at the KEK High Energy Accelerator Research Organization Tsukuba meson factory. 'It weighs about the same as a single atom of helium and exists for only about one billionth of a trillionth of a second before it decays into other longer-lived, more familiar particles.' Scientists say the lifespan 'is nearly an eternity for a sub-atomic particle this heavy' and may require a change in current theory. Possible explanations for this include the particle being comprised of two quarks and two antiquarks, instead of the usual one-one pairing. More explanation and illustrations at KEK."
from the Institute of Physics
When anger rises, think of the consequences.
Confucius (551 BC - 479 BC)
gotta love how they study something by smashing it into peices. I always pictured using the same technique to study how a radio works by shooting bullets into it, and then observing the peices as they fly out of the radio :-)
I Am My Own Worst Enemy
Save Sam and Max!
How do we know that you didn't have a purple dragon in your garage for about one billionth of a trillionth of a second?
Overall, money invested in science has historically paid off at better than 10-1. You see a lot of projects that dead-end or don't produce all that much of value, but every once in awhile you get a major, bonanza strike. Problem is, you can't tell which projects will be the big hits until afterward, so it looks like a big waste of money.
:-)
It isn't. We're still benefiting (enormously!) from the basic research done in the 1950s; they had ideas back then we still haven't fully tapped. Every time someone looks back at one of those obscure reports and says "hey, wait a minute!".... it's a payoff. We have long, long since paid off the money we invested in the 1950s, and made a handsome profit to boot. Everything after that is gravy.
Research... the gift that keeps on giving.
"Another Contradiction" is much too strong a statement. The Standard Model has two problems (1) it doesn't play well with gravity, so it can't be the "final answer", and (2) it is so ridiculously successful that no one knows quite where to go next in theoretical particle physics. The SM is more or less able to give the right answer to any question we're able to ask it, right up to the edges of black holes or the first tiny fraction of a second after the birth of the universe. There are some problems too complex for our calculational techniques and approximations (i.e. we can't calculate the physics of many bound states precisely or derive human behavior), but there aren't really any contradictions. The recently reported new particle is more likely to lead us to tell us our calculational approximations aren't very good, rather than that something fundamentally new (though one can always hope!) Particle physicists are always hoping to find something fundamentally wrong with the standard model - it's just an extremely good approximation to the right answer, and until the approximation breaks down you don't know how to improve it.
A college Philosophy professor of mine tells a story about high energy physics and the practitioners thereof. He was researching a book on the philosophy of science and was interviewing one of the researchers at Fermilab (I think).
After discussing some of the esoterica of the field, my professor says "Okay. Off the record, do you *actually* believe that some of these particles exist outside of mathematical equations?"
Scientist looks around and replies "Not really. But this stuff is a lot of fun!"
"As God is my witness, I thought turkeys could fly." A. Carlson
Probably not very much, but who knows? String theory generally deals with phenomena at energy scales MUCH higher than these accelerators are dealing with, so high in fact that it really doesn't make any useful predictions about ordinary phenomena (even particle accelerator phenomena!) It's sort of like trying to predict the shape of a snowflake if all you've ever seen is steam. That's one of the main complaints about the theory - it may be right, it may be wrong, but it doesn't have any major prospects for predictions we could even test!
>
> Spend the money on Earth sciences or, heck, build a dozen stations on the moon and start beaming energy down here. That would benefit the whole world and it can be done NOW.
~ wavy lines as the Time machine takes us back to 1908, where the poster's great-grandfather is ranting at "Printdot" ~
~ Thus endeth the flashback ~
Just one more sensation out of misunderstood
//charge +1 //charge -1 //charge 0 //charge 0 //charge 0
//charge +1 //charge 0 //charge -1
scientific paper.
I work with the team which confirmed it at Fermi in X(3872) -> J/Psi Pion Pion.
Some background on quarks first:
There are six quarks d, u, s, c, b, t. The heaviest are on the right.
And six antiquarks d(bar), u(bar), s(bar)... you've got the idea.
d, s, b have charge -1/3.
u, c, t have charge 2/3,
antiquarks and quarks have opposite charge.
All the matter consist of the particles which
are combinations of quarks. There are several
types of observed combinations: Mesons, Barions,
Tetraquarks, Pentaquarks. They are correspondingly
consist from 2, 3, 4 or 5 quarks.
All the Mesons consist of quark and antiquark. Examples:
Pion = (u, d(bar));
Kaon =(s, u(bar));
J/Psi =(c, c(bar));
D =(c, u(bar));
D(bar)=(c(bar), u);
Barions consist of 3 quarks. Examples:
Proton =(u, u, d );
Neutron =(d, d, u );
Antiproton =(u(bar), u(bar), d(bar));
You may continue it yourself for Tetraquarks and Pentaquarks.
Make sure the total charge of the particle is integer.
Heavy quarks want to decay to a ligter ones.
Eventually to u, d, u(bar), d(bar) and also
leptons (electron, muon) neutrinos and photons.
Some people think that X(3872) is one of the exited states of (c, c(bar)). Some people think
that it could be a tetraquark (c, c(bar), u, u(bar)). We should observe other modes
to know for sure. I am looking for X(3872) -> DD (bar).
No luck so far.
It is definitely very exiting to see a new particle like it would be exiting
to see a new chemical element. As far as I know it fit quite nicely
in the standard model - the analog of the Mendeleev table for particle physics.