Submitted by sulmer on

The IUPAP Prize for Atomic, Molecular, and Optical Physics 2019 was awarded to the BASE members Christian Smorra (RIKEN and CERN) and Andreas Mooser (RIKEN and MPIK). The highly competitive research prize was awarded…

“…for outstanding contributions to determine the most precise comparison of the proton-to-antiproton charge-to-mass ratios and the most precise comparison of the proton and antiproton magnetic moments, constituting two different world-record tests of the fundamental charge, parity, and time reversal symmetry in these systems.

We congratulate Christian and Andreas with pleasure to this great success!!!


Christian Smorra joined the RIKEN group in BASE as a post-doc in 2012, within his work he designed major parts of the BASE apparatus, contributed to the high-precision measurement of the proton-to-antiproton charge-to-mass ratio, and the invention and commissioning of the BASE reservoir-trap method. In 2017, in the framework of a CERN-fellowship, he published a 1.5 p.p.b. measurement of the magnetic moment of the antiproton using a newly invented two-particle / three trap method. This result improves upon previous best competing Penning trap efforts by more than a factor of 3000. In 2018 he became co-spokesperson of the BASE collaboration, still being a member for RIKEN Fundamental Symmetries Laboratory, within this position he is currently leading the BASE-Mainz experiment.


Andreas Mooser performed the first direct high-precision measurement of the magnetic moment of the proton with a fractional precision of 3.3 p.p.b.. He joined BASE’s RIKEN group in 2014 in the framework of a competitive RIKEN FPR fellowship, and was working at BASE-CERN in the 2014/2015 antiproton runs. As a RIKEN fellow he continued working at BASE-Mainz until 2018, under his supervision the Mainz team improved the precision of the proton magnetic moment to the level of 300 p.p.t. and started implementing methods to sympathetically cool protons with laser cooled Be+ ions. Since 2018 he is leading a Max Planck/RIKEN research group at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany, in the framework of the MPG-RIKEN-PTB Center for Time, Constants and Fundamental Symmetries.  


The award of the prize is without any doubt a great honour for the BASE collaboration, however only possible thanks to the strong and very generous support by RIKEN (Japan), the Max Planck Society (Germany), and CERN (Switzerland). We would like to thank the fantastic AD-operators team, CERN’s engineering departments, CERN’s cryolab for the everlasting and reliable support, and all the other CERN groups which are supporting us.

IUPAP Prize for Atomic, Molecular, and Optical Physics 2019 awarded to BASE members Christian Smorra and Andreas Mooser