ALPHA is an international collaboration based at CERN, and which is working with trapped antihydrogen atoms, the antimatter counterpart of the simplest atom, hydrogen. By precise comparisons of hydrogen and antihydrogen, the experiment hopes to study fundamental symmetries between matter and antimatter.


CERN People

22 Feb 2012

ALPHA is featured in a new documentary following life at CERN. See the first video on youtube or check out the film's page for more articles and videos.

The Carlsberg Foundation of Denmark has awarded a large research grant to ALPHA Spokesperson Professor Jeffrey Hangst of Aarhus University.  The award, of 3.3 million Danish kroner, will be used to purchase a new superconducting solenoid magnet for our next generation antihydrogen trapping device, known as ALPHA-2.  In 2012, the ALPHA-2 machine will replace the current ALPHA device, which is the first (and so far the only) machine to magnetically trap atoms of antihydrogen.  The new apparatus will allow ALPHA researchers to begin precision laser and microwave spectroscopy of trapped antimatter atoms.  The goal is to test whether atoms of matter and atoms of antimatter obey the same laws of physics.  The Carlsberg Foundation was created by Carlsberg founder J.C. Jacobsen in 1876 and has a long history of supporting scientific research in Denmark.  We in ALPHA would like to thank the Carslberg Foundation for their generous support.

The American Physical Society Division of Plasma Physics awarded its John Dawson award for excellence in plasma physics research to several ALPHA members. Will Bertsche, Paul Bowe, Mike Charlton, Joel Fajans, Makoto Fujiwara, Jeffrey Hangst, Niels Madsen, Francis Robicheaux, Daniel Silveira, Dirk Van der Werf and Jonathan Wurtele were cited "For the introduction and use of innovative plasma techniques which produced the first demonstration of the trapping of antihydrogen."

A schematic of the ELENA ring, to be built at the CERN AD.

The first construction meeting for the Extra-Low ENergy Antiproton (ELENA) Ring kicks off at CERN today. ELENA, approved by the CERN research board last July, is an additional ring in the Antiproton Decelerator (AD) building, designed to slow the 3.5 MeV beam from the AD to 100keV before delivering the beam to the experiments. What this means for experiments like ALPHA is that we can use much thinner matter foils to slow the antiproton beam down before capturing them in the trap, which in turn can mean a hundredfold increase in capture efficiency.

The meeting involves presentations from the experiments on past achievements, and future goals, from the CERN departments on the technical challenges and plans to meet them, and from external institues, committing financial and technical add to the project.

Read more at the CERN press release.

In a paper published online at Nature Physics, ALPHA announces confinement of antihydrogen atoms for at least 1000s.

Last November, we announced in Nature that we had successfuly trapped 38 antihydrogen atoms for at least 172 ms.  In fact, 172 ms is the shortest time we can trap atoms and be sure that we've removed all of the other particles that can be around. By simply leaving the magnetic atom trap on, we can easily make measurements for longer times.

Our complete data set from last year is made up of 309 annihilation events consistent with antihydrogen annihilation, 19 of which occur after holding the trap for at least 1000s. In the figure here, we show the number of atoms trapped as a function of the confinement time.

These results strongly imply that the antihydrogen atoms have reached their lowest-energy (ground) state while in the trap, which is important for the ground-state spectroscopy that ALPHA plans to perform on the trapped atoms. In addition, the large number of atoms allow us to compare the time and position at which the atoms escape the trap to simulations and shed light on the energy distribution of the trapped atoms.

Read more about the results here or read the full paper. See the news sites reporting on this story.