Dynamics of molecular beams in a traveling-wave Stark decelerator

Artem Zapara

Published Jan 1, 2019• 2 citations

Abstract

Physicists have observed all the elementary particles predicted by the Standard Model. These particles, however, account for only 5% of the total mass-energy of the Universe. In the quest to solve the mystery of missing matter and to extend our knowledge about nature, a large number of experimental research programs are devoted to find a glimpse of New Physics. Table-top high precision measurements on molecules can contribute to these efforts in a manner complementary to high-energy experiments at colliders. In this thesis, we describe the operation of a traveling-wave Stark decelerator. This device is designed and constructed in order to slow down heavy polar molecules for various future explorations. Deceleration is achieved by manipulation of the molecules in controllable electric fields. We demonstrate in an experiment the successful operation of the Stark decelerator by slowing down a beam of SrF molecules to one-third of their initial velocity, thus removing almost 90% of the initial kinetic energy. We also reveal limiting conditions for this process. These results are of importance for many exciting experiments using heavy molecules in the near future. One relevant and promising example of such experiments is the search for a permanent electric dipole moment of the electron.

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