Researchers with ALPHA, an international collaboration based at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, claim to have made the first ever measurement of antimatter on the optical spectrum, according to a report from Phys.org.
The researchers used a hydrogen atom in their research because, with only one proton and one electron, it is “the most abundant, simple and well-understood atom in the Universe.” It’s measurements as observed on the light spectrum are well-studied and understood.
Despite the abundance of information on hydrogen atoms available to scientists, there is very little knowledge of antihydrogen atoms and their antiprotons and positrons, Phys.org explains. This is partly due to the fact that antihydrogen atoms must be “produced and assembled.”
“It’s a painstaking process, but well worth the effort since any measurable difference between the spectra of hydrogen and antihydrogen would break basic principles of physics and possibly help understand the puzzle of the matter-antimatter imbalance in the universe,” according to Phys.org.
— Motherboard (@motherboard) December 19, 2016
ALPHA’s observation of the antimatter atoms supports some fundamental theories and expectations about how the characteristics of antihydrogen, and to some extent antimatter in general, could be observed.
“Today’s ALPHA result is the first observation of a spectral line in an antihydrogen atom, allowing the light spectrum of matter and antimatter to be compared for the first time,” the Phys.org article says. “Within experimental limits, the result shows no difference compared to the equivalent spectral line in hydrogen. This is consistent with the Standard Model of particle physics, the theory that best describes particles and the forces at work between them, which predicts that hydrogen and antihydrogen should have identical spectroscopic characteristics.”
While the fact that antimatter being observed on the light spectrum may seem to have simply reinforced the general expectations of physicists, it is nevertheless a major breakthrough in the study of physics.
“This achievement features technological developments that open up a completely new era in high-precision antimatter research,” Phys.org reports. “It is the result of over 20 years of work by the CERN antimatter community.”
Jeffrey Hangst, a spokesperson for the ALPHA collaboration, echoed this sentiment.
“Using a laser to observe a transition in antihydrogen and comparing it to hydrogen to see if they obey the same laws of physics has always been a key goal of antimatter research,” Hangst said, according to Phys.org.
Indeed, ALPHA’s research is being widely regarded as a breakthrough and milestone in the scientific community.
“WOW,” Randolf Pohl, a spectroscopist at Johannes Gutenberg University in Mainz, Germany, exclaimed in an email to the journal Nature quoted by Scientific American’s Davide Castelvecchi.
For the first time, researchers have measured how antimatter absorbs light https://t.co/uTCipjRNIx
— Scientific American (@sciam) December 20, 2016
“After all these years, these guys have finally managed to do optical spectroscopy in antihydrogen,” Pohl said. “This is a milestone in the investigation of exotic atoms.”
Michael Peskin, a theoretical physicist at the SLAC National Accelerator Laboratory in Menlo Park, California, shared Pohl’s enthusiasm.
“It is amazing that one can control antimatter to an extent that this is possible,” Peskin said.
ALPHA plans to study antihydrogen antimatter with even greater precision in the future to search for possible distinctions in the way that matter and antimatter may behave in order to “further test the robustness of the Standard Model,” Phys.org notes.
As mentioned above, it’s a complicated and painstaking process.
ALPHA uses CERN’s Antiproton Decelerator to create antihyrodgen atoms and contain them in a “magnetic trap.”
“Moving and trapping antiprotons or positrons is easy because they are charged particles,” Hangst said. “But when you combine the two you get neutral antihydrogen, which is far more difficult to trap, so we have designed a very special magnetic trap that relies on the fact that antihydrogen is a little bit magnetic.”
This is definitely amazing work on antimatter coming out of ALPHA, and we look forward to hearing more from them. Observed antimatter is surely just one of the breakthroughs to come from ALPHA.
[Featured Image by Getty Images/Peter Macdiarmid]