Researchers Dig Deeper On Why The Universe Is Made Up Of Matter; New Tool Is Used
Scientists around the world including the team of Stefan Ulmer from RIKEN are designing and carrying out high-precision measurements to an attempt of discovering fundamental dissimilarities between matter and antimatter. They are trying to reveal if it could lead to some discrepancy.
In a research published in Nature Communications, the team of Ulmer found that the magnetic moment of the antiproton is extremely close to that of the proton. The experts used a sophisticated technique with six-fold higher accuracy than the previous one. It involves individual particles to be trapped in a magnetic field.
In the study, the researchers took antiprotons generated by CERN's Antiproton Decelerator and placed them into a powerful magnetic field, which is called Penning trap. To get the measurements, they took individual antiprotons from containment trap and transferred them into another trap, where they were cooled to nearly absolute zero and put into a powerful complex magnetic field. It then allows the research team to measure the magnetic moment, according to IFL.
Phys.org reported that the group found, based on six measurements done using this method, that the moment (g-factor) of the antiproton is 2.7928465(23), while that of the proton was previously found to be 2.792847350(9) -- with the number in parentheses indicating the amount of uncertainty in the final digits. This puts the two measurements to both absolute, rather than relative ones to within 0.8 parts per million of one another.
Ulmer said that, "We see a deep contradiction between the standard model of particle physics, in which the proton and antiproton are identical mirror images of one another, and the fact that on cosmological scales, there is an enormous gap between the amount of matter and antimatter in the universe. "
He added that, "Our experiment has shown, based on a measurement six times more precise than any done before, that the standard model holds up, and that there seems, in fact, to be no difference in the proton/antiproton magnetic moments at the achieved measurement uncertainty. We did not find any evidence of CPT violation."