BASE Penning Trap System (IMAGE) Johannes Gutenberg Universitaet Mainz Caption This is the BASE Penning trap system that was used to measure the magnetic moment of the antiproton. Credit photo/©: Georg Schneider, JGU Usage Restrictions This image may only be used in connection with the press release "Magnetic moment of a single antiproton determined with greatest precision ever", issued by Johannes Gutenberg University Mainz on January 19, 2017. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.