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BigJim
2003-Jun-13, 11:48 PM
http://www.bnl.gov/bnlweb/pubaf/pr/2003/bnlpr061103.htm

Be sure to read the background information if you haven't heard about it yet. Interesting, isn't it? Would this "quark-gluon soup" be the same thing that appears to make up the "quark stars"?

Psi-less
2003-Jun-14, 02:12 AM
I know this is a really stupid question :oops: and I have to do a lot more reading before more than half of that article makes any sense, but is there a particular reason why they use gold ions? Is it believed to have been more common or is there a particular property to it that makes it more suitable? Inquiring minds want to know!

Psi-less

tracer
2003-Jun-14, 02:26 AM
Yeah, you'd think they'd use lead and try to turn it into gold. ;)

ToSeek
2003-Jun-14, 02:34 AM
Another thread, same topic (http://www.badastronomy.com/phpBB/viewtopic.php?t=6234)

tracer
2003-Jun-14, 02:39 AM
Would this "quark-gluon soup" be the same thing that appears to make up the "quark stars"?
Quark stars are thought to be made up of "strange quark matter" -- and by "strange", they don't merely mean odd, they mean specifically strange-flavored quarks, the counterpart to charm-flavored quarks. (Particles consisting of 1 or more strange quarks have thus far only been seen in high-energy particle accelerators, and their half-lives are measured in microseconds or picoseconds.)

A quark-gluon soup would presumably consist primarily of good old-fashioned garden-variety up-flavored and down-flavored quarks, the same kinds of quarks that make up common household protons and neutrons.

Grey
2003-Jun-14, 03:40 AM
I know this is a really stupid question :oops: and I have to do a lot more reading before more than half of that article makes any sense, but is there a particular reason why they use gold ions? Is it believed to have been more common or is there a particular property to it that makes it more suitable? Inquiring minds want to know!
They'll be using a variety of heavy ions, but gold is a favorite choice. Having large nuclei provides a lot of energy and particles to interact, so that's good, but it's also good to have a high particle density. As nuclei continue to get larger, though, the density of the nucleus actually starts to decrease a little, so gold ends up being a nice compromise between having a heavy nucleus with a reasonably high nuclear density.


Yeah, you'd think they'd use lead and try to turn it into gold. :wink:
They can do that pretty easily in an accelerator. Unfortunately, with the quantities that particle accelerators work with (RHIC will use less than a gram of gold over 20 years), and the amount of energy it takes, it not a particularly cost-effective undertaking. :(

Psi-less
2003-Jun-14, 02:26 PM
Thanks, Grey, that makes sense! Now, to do some more reading on quarks.

Psi-less

jkmccrann
2005-Dec-01, 09:12 AM
Who decided on these names for quarks? Charm & Strange, Up & Down are all very peculiar examples of scientific terms. And aren't there 2 more that I can't remember. If it does one thing though, I guess it kinda personalises these particles to the general public, in a way.........

Swift
2005-Dec-01, 03:49 PM
top and bottom
I love the names, though I don't know who named them

Kaptain K
2005-Dec-01, 06:50 PM
Just goes to show that scientists have a (very quirky) sense of humor. The word "quark" comes from Finnegans Wake, by James Joyce - "Three quarks for muster mark" (what ever that means :think: ). Then there's "gluons" that "glue" quarks together. Or the "axion", a particle named for a laundry detergent. Not to mention "wimps" (Weakly Interacting Massive Particles) and "machos" (Massive And Compact Halo Objects).

Kullat Nunu
2005-Dec-01, 08:06 PM
top and bottom
I love the names, though I don't know who named them

They're so boring names. Truth and Beauty were much better, but alas they're not used anymore.

jkmccrann
2005-Dec-02, 04:00 AM
How can they be Truly beautiful if we can't see them?

publiusr
2005-Dec-02, 10:47 PM
Now let me get this straight. A Quark star is between a neutron star (that still has recognizable carbon and oxygen down in it) and a black hole, right?

Kullat Nunu
2005-Dec-02, 11:17 PM
Neutron stars are thought to consist of primarily neutrons (which don't normally survive outside atom nuclei). Yet-to-be confirmed quark stars consist of free quarks (which don't survive outside protons or neutrons). Therefore a quark star is somewhat denser than a neutron star.

Kullat Nunu
2005-Dec-02, 11:23 PM
Normal matter has only two quarks, Up and Down. The matter in these stars have additional type of quarks, the Strange quark. Therefore this matter is sometimes called "strange matter" (it may have some really weird properties, so the name is really apt).