Image of the week - All about ALICE
Also known as A Large Ion Collider Experiment, ALICE is a massive physics experiment that will help physicists learn more about how matter was created and what it is made of.
ALICE will allow researchers to study the primordial “soup” of elementary particles that existed microseconds after the Big Bang.
Called Quark-Gluon Plasma, this cosmic “soup” is created when protons and neutrons melt into new forms of matter. This occurs at temperatures 100,000 times hotter than the center of the Sun, and under enormous pressures: so great that the pyramid of Kheops could be compressed into a pinhead.
Enter the LHC
These extraordinary conditions will be created inside the Large Hadron Collider, an underground particle accelerator that will become the world’s largest machine when it starts up next year.
The LHC works by shooting beams of sub-atomic particles around its 27 kilometer circular racetrack. Using magnets, the speed of these particles is increased until the beams are traveling at close to the speed of light. Despite their huge velocity, the particles are so small that their kinetic energy is similar to that of a flying mosquito.
When two counter-running particles collide head-on inside the ALICE detector, their energy is concentrated into a volume 100 billion times smaller than that of a mosquito, thus creating the energy density required to trigger creation of the Quark-Gluon Plasma “soup.”
These collisions occur about 8000 times every second and the particles produced leave behind millions of tracks. The ALICE detectors record these tracks to a fraction of a millimeter, creating as many as three DVDs of data every minute.
All this data is stored and then internationally distributed to thousands of collaborators via the Worldwide Large Hadron Collider Grid.
The world’s physicists are then free to study this information from the comfort of their own desks, searching for signs that may lead humanity to a new understanding of the universe.
Even the kids can share in the excitment: why not join ALICE in the adventure cartoon: Alice and the soup of quarks and gluons.
This year the ALICE team was recognized as a winner of the Computerworld “Best Practices in Storage” awards, in the category of Systems Implementation. The winning ALICE data-acquisition system can buffer up to eight hours of data, reading and writing data linearly by separating the two data streams to different discs. This innovation allowed the team to exceed their goal of 2.5 GB per second—the same rate as roughly 84 million mobile phone calls per second.
ALICE is hosted at CERN, the European Laboratory for Nuclear Research, and involves an international collaboration of more than 1000 researchers from 30 countries.