Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

CERN group traps antihydrogen atoms for more than 16 minutes

06.06.2011
ALPHA collaboration readying experiments to probe antihydrogen energy levels

Trapping antihydrogen atoms at the European Organization for Nuclear Research (CERN) has become so routine that physicists are confident that they can soon begin experiments on this rare antimatter equivalent of the hydrogen atom, according to researchers at the University of California, Berkeley.

"We've trapped antihydrogen atoms for as long as 1,000 seconds, which is forever" in the world of high-energy particle physics, said Joel Fajans, UC Berkeley professor of physics, faculty scientist at Lawrence Berkeley National Laboratory and a member of the ALPHA (Antihydrogen Laser Physics Apparatus) experiment at CERN in Geneva, Switzerland.

The ALPHA team is hard at work building a new antihydrogen trap with "the hope that by 2012 we will have a new trap with laser access to allow spectroscopic experiments on the antiatoms," he said.

Fajans and the ALPHA team, which includes Jonathan Wurtele, UC Berkeley professor of physics, will publish their latest successes online on June 5 in advance of print publication in the journal Nature Physics. Fajans, Wurtele and their graduate students played major roles in designing the antimatter trap and other aspects of the experiment.

Their paper reports that in a series of measurements last year, the team trapped 112 antiatoms for times ranging from one-fifth of a second to 1,000 seconds, or 16 minutes and 40 seconds.

Since the experiment first successfully trapped antihydrogen atoms in 2009, the researchers have captured 309.

"We'd prefer being able to trap a thousand atoms for a thousand seconds, but we can still initiate laser and microwave experiments to explore the properties of antiatoms," Fajans said.

In November 2010, Fajans, Wurtele and the ALPHA team reported their first data on trapped antihydrogen: 38 antiatoms trapped for more than one-tenth of a second each. They succeeded in capturing an antiatom in only about one in 10 attempts, however.

Toward the end of last year's experiments, they were capturing an antiatom in nearly every attempt, and were able to keep the antiatoms in the trap as long as they wanted. Realistically, trapping for 10-30 minutes will be sufficient for most experiments, as long as the antiatoms are in their lowest energy state, or ground state.

"These antiatoms should be identical to normal matter hydrogen atoms, so we are pretty sure all of them are in the ground state after a second," Wurtele said.

"These were likely the first ground state antiatoms ever made," Fajans added.

Antimatter is a puzzle because it should have been produced in equal amounts with normal matter during the Big Bang that created the universe 13.6 billion years ago. Today, however, there is no evidence of antimatter galaxies or clouds, and antimatter is seen rarely and for only short periods, for example during some types of radioactive decay before it annihilates in a collision with normal matter.

Hence the desire to measure the properties of antiatoms in order to determine whether their electromagnetic and gravitational interactions are identical to those of normal matter. One goal is to check whether antiatoms abide by CPT symmetry, as do normal atoms. CPT (charge-parity-time) symmetry means that a particle would behave the same way in a mirror universe if it had the opposite charge and moved backward in time.

"Any hint of CPT symmetry breaking would require a serious rethink of our understanding of nature," said Jeffrey Hangst of Aarhus University in Denmark, spokesperson for the ALPHA experiment. "But half of the universe has gone missing, so some kind of rethink is apparently on the agenda."

ALPHA captures antihydrogen by mixing antiprotons from CERN's Antiproton Decelerator with positrons – antielectrons – in a vacuum chamber, where they combine into antihydrogen atoms. The cold neutral antihydrogen is confined within a magnetic bottle, taking advantage of the tiny magnetic moments of the antiatoms. Trapped antiatoms are detected by turning off the magnetic field and allowing the particles to annihiliate with normal matter, which creates a flash of light.

Because the confinement depends on the antihydrogen's magnetic moment, if the spin of the antiatom flips, it is ejected from the magnetic bottle and annihilates with an atom of normal matter. This gives the experimenters an easy way to detect the interaction of light or microwaves with antihydrogen, because photons at the right frequency make the antiatom's spin flip up or down.

Though the team has trapped up to three antihydrogen atoms at once, the goal is to trap even more for long periods of time in order to achieve greater statistical precision in the measurements.

The ALPHA collaboration also will report in the Nature Physics paper that the team has measured the energy distribution of the trapped antihydrogen atoms.

"It may not sound exciting, but it's the first experiment done on trapped antihydrogen atoms," Wurtele said. "This summer, we're planning more experiments, with microwaves. Hopefully, we will measure microwave-induced changes of the atomic state of the antiatoms."

The work of the ALPHA collaboration is supported by numerous international organizations, including the Department of Energy and the National Science Foundation in the United States.

Among the paper's 38 authors are UC Berkeley graduate students Marcelo Baquero-Ruiz and Chukman So.

Robert Sanders | EurekAlert!
Further information:
http://www.berkeley.edu

Further reports about: Big Bang CERN CPT Nature Immunology Nature Physics hydrogen atom magnetic moment

More articles from Physics and Astronomy:

nachricht New NASA study improves search for habitable worlds
20.10.2017 | NASA/Goddard Space Flight Center

nachricht Physics boosts artificial intelligence methods
19.10.2017 | California Institute of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>