Everyone's favorite particle smasher, the Large Hadron Collider (LHC) has almost reached 1.9 Kelvin (-465F), colder than deep space. Never before has a physics experiment so enormous and complex been operated at such extremely low temperatures.
It contains 7,000 magnets that will be maintained at colder than space temperatures using liquid helium, in order to make them superconducting. The magnets are arranged in a ring that runs through the underground tunnel.
Cooling the Collider is a process that takes a couple of weeks, and that's only if everything goes as planned. If a sector has to be brought back up to room temperature for inspection and repairs and then recooled, the project is setback for months. Of the LHC's eight sectors, six are at temperatures between 4.5 and 1.9 kelvin.
To put perspective on just how frigid these temperatures are, desolate regions of outer space are about 2.7 Kelvin. Two sectors are not cold enough to undergo electrical testing, and so their cooling equipment will be moved to an area that offers better protecttion against super fast colliding particles.
Spanning the border between Switzerland and France at about 100 m underground, the machine will mimick the conditions right after the Big Bang, when an extremely hot and dense universe underwent some cosmic explosion that created space and time as we know it today.
When up and running the LHC will excite clusters of protons to record-breaking high energies, and then smash them into each other 30 million times a second.
Among the particle debris left over from these collisions, scientists hope to find the Higgs boson ( you know, the "god particle"), and the particle that makes up the identity of dark matter.
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Monday, July 21, 2008
Large Hadron Collider: Colder Than Deep Space
Wednesday, June 25, 2008
Blogosphere Reacts to LHC Report
"Breaking: LHC Still Will Not Destroy the Earth"
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Monday, June 02, 2008
Magnetosphere Mondays
An exciting way to start off the week: Astrophysicists at NASA have recently discovered that energetic protons from the plasmasphere control pressure in the earth's magnetosphere. The term magnetosphere (aside from sounding sinister), is used to describe the surrounding region of planets dominated by a magnetic field, like Earth, Jupiter, Saturn, Uranus, and Neptune. The discovery challenges the way most scientists previously thought about the magnetosphere, as being most affected by solar wind.
They used a model to stimulate superstorm plasmas (the above picture shows what the Earth's magnetosphere looks like during a superstorm), which are often caused by sporadic ejections of solar material from the sun. These coronal mass ejections send billions of tons of plasma shooting out of the sun and hurling towards the earth at high speeds (millions of miles per hour).
Superstorm plasma isn't without its consequences on Earth, usually in the form of awesome visual displays like the Northern Lights (pictured to the right, as seen from Bear Lake, Alaska). But more damaging effects of plasma include disruption of communications between airplanes and satellites traveling near the North Pole, and suspending global positioning system and power grid functions.
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Wednesday, October 11, 2006
Matter/AntiMatter Molecule Created
Scientists at CERN, a giant particle accelerator straddling the border between France and Switzerland, have created the first molecule made of both matter and antimattter.
The researchers made the molecules by slowing antiprotons and letting them interact with hydrogen molecules, leading to molecules consisting of a single proton bound to a single antiproton, as well as leftover hydrogen atoms.
(Bear in mind that scientists have long ago managed to join electrons and positrons together into positronium, which is a lot like a molecule, but molecules really should have atoms in them, rather than just electrons and their antimatter positron partners.)
The researchers reported their work in this week's edition of Physical Review Letters.
Now the big question -- what do we call the stuff?
The CERN folks are going with "antiprotonic hydrogen." A bit hard on the tongue, I think.
My friends at Physics News Update (PNU), who reported the story first, like "protonium." That's probably the best bet, but if we are following convention established with positronium (which is named after the antimatter particle), it should be called "antiprotonium."
Wikipedia already has an entry for protonium, so I think my PNU friends have made the right call.
Regarding the graphic above, you can't really take pictures of atoms and small molecules, but these shapes (spherical harmonics) are closer to the way hydrogen atoms would actually look if you could see them. If CERN releases images of protonium/antiprotonium/anitprotonic hydrogen, I'll post those instead.
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Thursday, September 28, 2006
PASER schmazer
You know what a laser is of course. The term stands for Light Amplification by Stimulated Emmission of Radiation. You may not know that they were based on principles developed with the maser (Microwave Amplification by Stimulated Emmission of Radiation), and have led to the saser(a sound laser). Now there's the paser, a particle version of the laser.
A paper in this week's Physical Review Letters describes the first paser. You can read more about it on the American Institute of Physics web page Physics News Update.
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