Cold antiProtons for Better Antimatter Research

The matter-antimatter asymmetry is a major unsolved problem in physics: Why do we live in a universe dominated by matter although physics tells us that equal amounts of matter and antimatter have been created at the Big Bang?The AEgIS project at CERN studies this problem by measurements of antihydrogen.

Just last year, AEgIS achieved the pulsed formation of antihydrogen and enters now a new era of antimatter research, measuring the gravitational acceleration of antihydrogen and forming new, more complex antiprotonic atoms for spectroscopic investigation.However, the sensitivity of these measurements is limited by the thermal motion of antiprotons, in the case of pulsed formation of a neutral antihydrogen beam.

The antiproton temperature could be lowered drastically by thermalization with laser-cooled ions.

Laser-cooling, however, has never been realized with negative ions, as needed for cooling antiprotons, because almost no atomic anions do have strong optical transitions suitable for laser cooling.The goal of this project is to demonstrate laser cooling of the diatomic carbon anion – making it the first negative ion and the first molecular ion to be laser cooled.

To reach this challenging goal, we will use an interdisciplinary approach, making use of the complementary backgrounds of the applicant (molecular physics) and the host (elementary particle physics).The impact of this project goes beyond antimatter research.

Laser-cooled diatomic carbon anions can cool any other negative ion, thus enabling new experiments in atomic and molecular physics or physical chemistry.

Furthermore, the transdisciplinary knowledge transfer between the host and the applicant, and the bridges built between atomic/molecular physics and antimatter research will lead to new research initiatives, keeping Europe at the forefront of this emerging, interdisciplinary field.