Our Methods Produce the World's Coldest Antiprotons

Before our methods: Lowest antiproton energy was 21 MeV antiprotons from LEAR at CERN (later reduced to 5 MeV)

After our methods: Antiprotons with more than 10¹⁰ times less energy (0.3 milli-eV, 4.2 Kelvin)

Applications

• Our comparison of Q/M for the antiproton and proton to 9 parts in 10¹¹
• All slow antihydrogen experiments require and use these methods (ATRAP, ATHENA, ALPHA, AEGIS, ASACUSA)

Our Methods Slow some of these antiprotons within matter Capture them in an ion trap for the first time Cool them via collisions with 4.2 K electrons Accumulate antiprotons from successive injections ("stacking")

Electrodes we used to trap the first antiprotons A popular account gives the story of how an initially unfunded postdoc, with his untenured friends and new students, set out on two 24-hour, foolhardy excursions to CERN to prove that they can slow and trap antiprotons for the first time. A review summarizes the low energy antiproton methods that would later make it possible to make slow antihydrogen atoms.