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Closing In On The Quark-Gluon Plasma
Martin writes "A series of presentations and a press conference was held today at Brookhaven National Laboratory about new
results from the Relativistic
Heavy Ion Collider. The latest run was finished only a few weeks
ago. The results are a new milestone in the search for the Quark-Gluon Plasma, a new
state of nuclear matter. The data were analyzed on large
Linux clusters at BNL and in Japan and France, with the biggest cluster of
about 1100 dual-CPU nodes located at the RHIC
Computing Facility. It's nice to see that results are out so soon
after the data were taken. There were previous stories about RHIC on /.,
here(1),
here(2)
and here(3)."
Pretty cool.
I don't know what half this stuff means. But I think it's cool that someone else does.
g yulass y/Welcome.html).r 06110 3.htm.)
Here's the body of the email update:
INTRIGUING ODDITIES IN HIGH-ENERGY NUCLEAR COLLISIONS. Missing
debris in the smashup between gold nuclei going at close to the
speed of light suggests the creation of a highly unusual plasma
environment, researchers have announced at Brookhaven National
Laboratory. By smashing together gold ions at Brookhaven's
Relativistic Heavy Ion Collider (RHIC), scientists are attempting to
make and study a state of matter that existed only millionths of a
second after the big bang. Called a quark-gluon plasma (QGP), it is
a hot, dense soup of individual quarks and gluons. In today's
universe, by contrast, quarks come in groups of twos and threes,
held together by gluons. This spring, Brookhaven researchers
performed a "control" experiment, in which they collided a gold
nucleus with a deuteron, a light nucleus consisting of just a proton
and neutron. In these and other kinds of nuclear collisions, a pair
of quarks from a proton or neutron occasionally gets ejected. In
turn each ejected quark produces a stream or "jet" of particles in
its wake. In some of the gold-deuteron collisions, the researchers
indeed observed pairs of jets flying in opposite directions. But in
head-to-head collisions between two gold nuclei, researchers
observed only one, rather than two, jets. This property, called jet
quenching, suggests that the particle jet traveling in the direction
of the collision region is getting absorbed by a hot, dense state of
matter. Jet quenching is predicted to occur in the correspondingly
hot, dense environment of a quark-gluon plasma, but RHIC
experimentalists are not ready to claim the QGP prize quite yet. To
verify its presence and rule out rival scenarios, they are planning
numerous other experiments for finding other signatures of a QGP.
However, the new data has convinced Columbia theorist Miklos
Gyulassy that the RHIC team is already seeing a QGP (see
http://www-cunuke.phys.columbia.edu/people/
The gold-gold collisions, he and his colleagues calculate, produce
an environment 100 times denser than ordinary nuclear matter and
display properties predicted in QGP models based on quantum
chromodynamics (QCD), the theory of the strong force which holds
nuclei together. On June 18, three of the four RHIC experimental
groups have submitted papers on the new results to Physical Review
Letters and researchers discussed these new results at a special
Brookhaven colloquium today. (Brookhaven press release, June 11,
http://www.bnl.gov/bnlweb/pubaf/pr/2003/bnlp
Isn't this the same thing they said about Lasers in the 50s?
I read the internet for the articles.
...Scientists can use these jets to probe your anus...
These article posting trolls seem to be gaining in popularity lately... Maybe because the mods don't take the time to read them fully before modding them up.
I'm going to name my band "Quark-Gluon Plasma". All my fans will call it "QGP" for short. It's much cooler than "Bose-Einstein Condensate".
On a slightly more serious note...
The article links to a helpful physics primer if you, like me, need a little help understanding subatomic physics. (I'm just have a lowly Math degree.)
A little googling turned up this awesome page on subatomic particles called The Particle Adventure. This is the most accessible physics lesson I've ever received. Awesome.
This is the most fun I've ever had with subatomic physics: Quark Dance!
obviously no deficiencies vs. no obvious deficiencies
Given they're physicists, methinks it's in Kelvins.
Here's a decent Nature article on QGP http://www.nature.com/nsu/000217/000217-5.html
In Soviet Russia, beowulf clusters imagine YOU!
This one doesn't seem to be in the catalogue of Start Trek Particles...
At least not yet.
Samsung took back my unlocked bootloader because Google wants me to rent movies. They're both evil.
The difference in the gravitational field of person and the satellites skews the GPS results somewhat. One needs to compensate for this to have a useable result for GPS.
Burn Hollywood Burn
It's early (or late..)for me but this is not what I read:
from the metaresearch link:
2. What relativistic effects on GPS atomic clocks might be seen? General Relativity (GR) predicts that clocks in a stronger gravitational field will tick at a slower rate. Special Relativity (SR) predicts that moving clocks will appear to tick slower than non-moving ones. Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth. So if a hypothetical clock at Earthâ(TM)s north or south pole is used as a reference, a clock at Earthâ(TM)s equator would tick slower because of its relative speed due to Earthâ(TM)s spin, but faster because of its greater distance from Earthâ(TM)s center of mass due to the flattening of the Earth. Because Earthâ(TM)s spin rate determines its shape, these two effects are not independent, and it is therefore not entirely coincidental that the effects exactly cancel. The cancellation is not general, however. Clocks at any altitude above sea level do tick faster than clocks at sea level; and clocks on rocket sleds do tick slower than stationary clocks. For GPS satellites, GR predicts that the atomic clocks at GPS orbital altitudes will tick faster by about 45,900 ns/day because they are in a weaker gravitational field than atomic clocks on Earth's surface. Special Relativity (SR) predicts that atomic clocks moving at GPS orbital speeds will tick slower by about 7,200 ns/day than stationary ground clocks. Rather than have clocks with such large rate differences, the satellite clocks are reset in rate before launch to compensate for these predicted effects. In practice, simply changing the international definition of the number of atomic transitions that constitute a one-second interval accomplishes this goal. Therefore, we observe the clocks running at their offset rates before launch. Then we observe the clocks running after launch and compare their rates with the predictions of relativity, both GR and SR combined. If the predictions are right, we should see the clocks run again at nearly the same rates as ground clocks, despite using an offset definition for the length of one second. We note that this post-launch rate comparison is independent of frame or observer considerations. Since the ground tracks repeat day after day, the distance from satellite to ground remains essentially unchanged. Yet, any rate difference between satellite and ground clocks continues to build a larger and larger time reading difference as the days go by. Therefore, no confusion can arise due to the satellite clock being located some distance away from the ground clock when we compare their time readings. One only needs to wait long enough and the time difference due to a rate discrepancy will eventually exceed any imaginable error source or ambiguity in such comparisons.
Different effects cancel eachother?
Is this what I read. And (this is what I read some where else) we wouldnt do anything different if it we never had GR or SR.
It was discredited with the simple truthful statement that a neutrino interacting with matter in the Earth could potentially release more energy than RHIC could generate in it's lifetime. i.e. higher energy reactions than those generated at RHIC occur all the time, all around us; and, we're still here.
of course, I'm paraphrasing a little...
...and almost every component in it is based on the results of pure, academic research that was performed with no immediate apparent application.
The laser, for example, was a curiosity sat around in research labs for a decade or more before anyone thought of anything to do with it.
It's official. Most of you are morons.
It's "hear, hear." "A shout of support or agreement. Originated in the British parliament in the 18th century as a contraction of 'hear him, hear him'. It is still often heard there although sometimes used ironically these days." http://phrases.shu.ac.uk/meanings/178100.html