io9: mad physics

Large Hadron Collider Less Than Two Weeks Away From First Experiments

Annalee Newitz — Fri, 13 Nov 2009 11:20:00 PST

It's been plagued by everything from liquid helium leaks to wayward baguettes, but the mega-physics experiment known as the Large Hadron Collider (LHC) is finally ready to start smashing protons into each other. Particle collisions could begin in two weeks.

The LHC is a 27-kilometer underground tunnel designed to accelerate atomic particles and smash them into each other. The goal is to see what happens when such particles interact with tremendous amounts of energy, the way they might under extreme conditions in outer space. The results of LHC experiments will reveal a lot about the origins of our universe, and the composition of matter within it.

CERN, the Swiss facility where the enormous underground experiment is located, has announced that test beams in the LHC have zoomed around most parts of the accelerator without incident:

Particles are smoothly making their way around the 27 km circumference of the LHC. Last weekend (7-8 November), the first bunches of injection energy protons completed their journey (anti-clockwise) through three octants of the LHC's circumference and were dumped in a collimator just before entering the CMS cavern. The particles produced by the impact of the protons on the tertiary collimators (used to stop the beam) left their tracks in the calorimeters and the muon chambers of the experiment.

One of the coolest parts about accelerators is that when the microscopic particles smash into the walls, they are moving so fast that they leave long tracks in their wakes. (Researchers can gain information from examining these tracks.)

If everything keeps moving smoothly, we could see some particle-on-particle smashage as early as two weeks from now. As long as the world doesn't end, we're going to get some long-awaited answers to our questions about our universe.

via CERN Bulletin

Experiment Where Scientists Locate 1 Atom in 10,000,000,000,000,000,000,000,000,000

Annalee Newitz — Wed, 06 May 2009 16:30:00 PDT

Over at the Enriched Xenon Laboratory (pictured) at Stanford, something very tiny is going on. So tiny, in fact, that it involves finding "a single barium atom in a 10 ton bath of liquid xenon–10^28 atoms." (That's 10,000,000,000,000,000,000,000,000,000 atoms to you.) Researchers are trying to observe something called "neutrinoless double beta decay," which must be cool because it involves anti-particles. I'll let Symmetry Breaking explain the weirdness:

This means watching for an isotope of xenon decaying into barium, giving off two electrons (the double beta decay), but without giving out any neutrinos. A beta decay process gives off one neutrino, so how could this even be possible? It only works if the neutrino is its own antiparticle, so that the two beta decays each have a neutrino which essentially cancel each other out, like matter and antimatter annihilating. And the possibility that process exists is the reason for the experiment.
If neutrinoless double beta decay is observed, it means the neutrino must be its own antiparticle, a key unknown in the study of neutrinos. If the neutrino is indeed its own antiparticle, it has all kinds of implications for the structure of the Standard Model and the relationships between the fundamental particles.

OK, now I understand both the plot of A Scanner Darkly and what will happen during the season finale of Fringe. It all totally makes sense now.

via Symmetry Breaking

Most Awesome Chemistry Machine at the Photon Factory

Annalee Newitz — Mon, 23 Mar 2009 12:30:00 PDT

This crazy machine is a new kind of microscope that can identify a chemical based on just a few atoms. Awesomely, it sucks up intense X-ray beams from a synchrotron to do it.

Developed by a research team in Japan, this method of magnifying the nanoverse is called Synchrotron Radiation Scanning Tunnelling Microscopy. Testing was a joint effort of the University of Hyogo and the KEK Photon Factory (best name evar). How does it work? According to Physics World:

It involves placing a sample of interest in the intense x ray beam of a synchrotron source.
Photons from the beam excite core electrons in the sample's atoms, which then spit out "secondary" electrons as they decay back down to their ground states. These secondary electrons are then detected by the tip of the scanning tunnelling microscope (STM) as they tunnel across the gap. The size of the current depends on the specific type of atom that has produced the secondary electrons, which means that each element has a unique "fingerprint."

I just want to know why the STM is covered in tinfoil. Or whatever that puffy, shiny stuff is. Also, that is seriously the coolest lab picture ever. Tangled wires! X-rays shooting everywhere! Hopefully somebody will get superpowers out of this.

via Physics World

First Particle Beam to Shoot Through the Large Hadron Collider Tomorrow

Annalee Newitz — Fri, 08 Aug 2008 10:36:29 PDT

The Large Hadron Collider (LHC) will smash up its its first proton beams this weekend in a test, arousing the fears of conspiracy lovers everywhere. If you'll recall, the LHC is that super-mega physics experiment in Switzerland's CERN Lab that some believe might destroy the world by producing black holes. Above, you can see a visualization of how large the facility is, as it loops under the ground outside Geneva. So what's in store tomorrow when the first beams start circling?

Physicists working on the LHC say that even if the device does produce tiny black holes, they will exist for such a short time that they couldn't possibly do any damage. Instead, they're interested in experiments that could reveal for the first time what dark matter is, and what the universe looked like after the big bang.

Though the LHC won't be in full operation until September 10, when the first real experiments there will get underway, this weekend marks the first time the facility will be used. Researchers will shoot a few particle beams through the magnetized, reinforced tunnels that make up the giant particle accelerator. According to Popular Mechanics:

As part of a scheduled injection test, the LHC will be closed off this Friday, and researchers at CERN will fire protons through one of the eight sectors that make up the sprawling concrete-lined collider tunnel. The purpose of this test? “It’s, ‘Let’s see what happens,’ ” says Judy Jackson, head of the Office of Communications at Fermilab. “It’s a very complex machine. This is a step towards getting ready.”

Let's see what happens? You mean, like whether it produces tiny black holes that last longer than a nanosecond? Awesome.

Start Date for the Large Hadron Collider [Popular Mechanics]

"Ghost" Photographs Created via Quantum Entanglement

Annalee Newitz — Mon, 30 Jun 2008 10:28:35 PDT

Within a few years, we'll be able to take clear pictures of objects through clouds, smoke, or fog. We'll do it using quantum entanglement cameras. How do you translate theoretical physics into photography? Imagine you are trying to photograph a boat behind a bank of fog. You'll use two light-sensitive devices: aim one at a light source that's illuminating your fog-shrouded boat (such as the sun, or a searchlight); then aim the other where you think the boat is likely to be. Then you use a computer program to combine the patterns of photons you've received from the object and the light.

Once the two patterns have been compared, you get a kind of black-and-white silhouette of the object you want to photograph. Scientists call this a "ghost photograph." University of Maryland physicist Yanhua Shih has been working on this "ghost photography" for a while, and has been talking to the military about using it in UAVs for photographing bomb damage through smoke.

According to the Air Force Times:

Albert Einstein explored the basic research behind ghost imaging — quantum entanglement — which he called "spooky action at a distance" in 1935. Shih discovered ghost imaging in 1995, but the theory has yet to leave the laboratory.
Air Force satellites could use ghost imaging by pointing a light sensor toward the Earth's surface and another toward the sun. The technique could allow the service to penetrate clouds or the smoke that follows airstrikes . . . Defense manufacturer Lockheed Martin has shown interest in quantum entanglement, acquiring a U.S. patent in May to develop quantum radar that could defeat stealth aircraft and find camouflaged improvised explosive devices and mines, according to the patent.

I'm still unclear on how this works if you don't know the precise location of the object you want to photograph.

Discovery May Make Ghost Imaging a Reality [Air Force Times]

Magnetic Fusion in the Spherical Torus Experiment

Annalee Newitz — Tue, 08 Jan 2008 10:40:10 PST

Right now, you are looking into a space where plasmas are crushed into a torus shape, subjected to a magnetic field, and then heated and pressurized until their nuclei fuse. It's called the National Spherical Torus Experiment. This glowing, sideways view of the chamber where plasmas undergo magnetic fusion was taken by Elle Starkman and Charles Skinner of the Princeton Plasma Physics Lab. Check out the exterior and a schematic for the chamber below (yes, several humans could fit inside it).

Here is the Spherical Torus from above in the Princeton Plasma lab:

And here's a schematic to give you a better idea of what it looks like.

Apparently plasma toroids are all the rage in physics circles right now, so it's time to get rid of all your old-fashioned plasma spheres and ovoids. Also, dear readers, if any physics geeks out there would care to explain the principles of magnetic fusion to us in layperson's terms we'd love to know.

National Spherical Torus Experiment