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View Full Version : New particle baffles physicists?



Irishman
2004-Jul-02, 09:10 PM
http://physicsweb.org/article/news/8/6/11


The heaviest of the nominal heavy-light mesons was discovered by the SELEX collaboration at Fermilab. It consists of a charm and a strange quark, producing a particle that decays in ways not predicted by quantum physicists.

ToSeek
2004-Jul-02, 09:32 PM
It will make the particle physicists happy. They keep looking for something that will break the Standard Model so they can try to put it back together again.

Gullible Jones
2004-Jul-03, 02:00 AM
Interesting. Very interesting.

Eta C
2004-Jul-03, 05:23 AM
I'm reading the preprint now. I've learned to distrust popular summaries of physics experiments. They usually mis-state things as they simplify. On the surface, there's nothing particularly unusual about the particle itself. C - S bar mesons fall directly into the standard model structure. What's unusual is the decay mode. I'll be back with any comments later this weekend.

Plat
2004-Jul-03, 05:32 AM
wow, we truly dont know anything about the universe

Eta C
2004-Jul-04, 11:44 PM
On the contrary, PtRhymer, we know a lot. We also don't know a lot which is why new discoveries always come along. But to pretend that we know nothing is disingenuous, insulting, and naive.

I've read the pre-print. It's an interesting result. However, it's too soon to say if it indicates new physics. To quote the paper (Fermilab Pub-04/087E, submitted to PRL)
SELEX reports these peaks as the first observation of yet another narrow, high-mass Ds state decaying strongly to a ground state charm plus a pseudoscalar meson. The mechanism which keeps this state narrow is unclear.
That is, there are several possible explanations. It may indicate new physics. The explanation may also turn out to be very prosaic. They sum up by saying
To place this new state in the spectroscopy of the charm-strange meson system will require careful study from a number of experiments in the future.
So, there's a lot of work to be done. Too soon to go jumping to conclusions.

Tensor
2004-Jul-04, 11:55 PM
I've read the pre-print. It's an interesting result. However, it's too soon to say if it indicates new physics. To quote the paper (Fermilab Pub-04/087E,

snip....

So, there's a lot of work to be done. Too soon to go jumping to conclusions.

Thank you Eta. I was waiting for your take. Thanks for the easy to understand explanation.

The Bad Astronomer
2004-Jul-05, 12:47 AM
wow, we truly dont know anything about the universe

Um, what? I think the fact that we even know about these kind of mesons points to the idea that we do indeed know quite a bit about it.

Morrolan
2004-Jul-05, 01:34 AM
i loove this stuff! i can still remember seeing a documentary back in the 70s about quark, strangeness and charm and it blew me away! that we have the ability to find out about these things fills me with admiration for the scientists working on this subject...

even if i have a hard time understanding the theories behind it... :(