A molecular synchrotron offers unique possibilities to study molecular collisions at low energies. For such a study, it is imperative that the velocity of the stored molecules can be tuned over a wide range. Bunching elements, used to provide the necessary longitudinal focusing forces in a synchrotron, introduce instabilities for certain velocities of the stored molecules. Here we present an experimental study of these motional resonances and show how they can be avoided. A packet of $\mathrm{N}{\mathrm{D}}_{3}$ molecules is stably confined in the synchrotron as its injection velocity is continuously scanned from $60\phantom{\rule{0.3em}{0ex}}\mathrm{m}∕\mathrm{s}$ $({E}_{\mathrm{kin}}=3.0\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1})\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}87.5\phantom{\rule{0.3em}{0ex}}\mathrm{m}∕\mathrm{s}$ $({E}_{\mathrm{kin}}=6.4\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1})$.A molecular synchrotron offers unique possibilities to study molecular collisions at low energies. For such a study, it is imperative that the velocity of the stored molecules can be tuned over a wide range. Bunching elements, used to provide the necessary longitudinal focusing forces in a synchrotron, introduce instabilities for certain velocities of the stored molecules. Here we present an experimental study of these motional resonances and show how they can be avoided. A packet of $\mathrm{N}{\mathrm{D}}_{3}$ molecules is stably confined in the synchrotron as its injection velocity is continuously scanned from $60\phantom{\rule{0.3em}{0ex}}\mathrm{m}∕\mathrm{s}$ $({E}_{\mathrm{kin}}=3.0\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1})\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}87.5\phantom{\rule{0.3em}{0ex}}\mathrm{m}∕\mathrm{s}$ $({E}_{\mathrm{kin}}=6.4\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1})$.

Physical Review ASep 23, 200812 citations

Atomic and Molecular Beams

Tosi, Paolo, Bassi, Davide

Springer eBooksJan 1, 2001180 citations

A novel molecular synchrotron for cold collision and EDM experiments

Shunyong Hou, Bin Wei, Lianzhong Deng +1 more

Limited by the construction demands, the state-of-the-art molecular synchrotrons consist of only 40 segments that hardly make a good circle. Imperfections in the circular structure will lead to the appearance of unstable velocity regions (i.e. stopbands), where molecules of certain forward velocity will be lost from the structure. In this paper, we propose a stopband-free molecular synchrotron. It contains 1570 ring electrodes, which nearly make a perfect circle, capable of confining both light and heavy polar molecules in the low-field-seeking states. Molecular packets can be conveniently manipulated with this synchrotron by various means, like acceleration, deceleration or even trapping. Trajectory calculations are carried out using a pulsed (88)SrF molecular beam with a forward velocity of 50 m/s. The results show that the molecular beam can make more than 500 round trips inside the synchrotron with a 1/e lifetime of 6.2 s. The synchrotron can find potential applications in low-energy collision and reaction experiments or in the field of precision measurements, such as the searches for electric dipole moment of elementary particles.Limited by the construction demands, the state-of-the-art molecular synchrotrons consist of only 40 segments that hardly make a good circle. Imperfections in the circular structure will lead to the appearance of unstable velocity regions (i.e. stopbands), where molecules of certain forward velocity will be lost from the structure. In this paper, we propose a stopband-free molecular synchrotron. It contains 1570 ring electrodes, which nearly make a perfect circle, capable of confining both light and heavy polar molecules in the low-field-seeking states. Molecular packets can be conveniently manipulated with this synchrotron by various means, like acceleration, deceleration or even trapping. Trajectory calculations are carried out using a pulsed (88)SrF molecular beam with a forward velocity of 50 m/s. The results show that the molecular beam can make more than 500 round trips inside the synchrotron with a 1/e lifetime of 6.2 s. The synchrotron can find potential applications in low-energy collision and reaction experiments or in the field of precision measurements, such as the searches for electric dipole moment of elementary particles.

Scientific ReportsSep 7, 20168 citations

Atomic and molecular beam experiments

Isidor Isaac Rabi, E. Montaldi

Il Nuovo CimentoJul 1, 19560 citations

A Forty-Segment Molecular Synchrotron

Peter C. Zieger, Chris J. Eyles, Sebastiaan Y. T. van de Meerakker +3 more

We present a synchrotron for polar molecules consisting of 40 straight hexapoles arranged in a circle with a 50 cm diameter. The mechanical design and alignment procedure as well as the trigger scheme used to switch the voltages applied to the hexapoles are described in detail. The stability of the synchrotron is demonstrated by measurements in which multiple packets are stored for over 13 s, during which they have completed over 1000 round trips and traveled a distance of over one mile. Furthermore, we demonstrate the simultaneous trapping of 26 packets; 13 revolving clock-wise and 13 counter clock-wise, that are injected into the synchrotron by two Stark decelerator beamlines. We discuss the opportunities for using the synchrotron as a low-energy collider.We present a synchrotron for polar molecules consisting of 40 straight hexapoles arranged in a circle with a 50 cm diameter. The mechanical design and alignment procedure as well as the trigger scheme used to switch the voltages applied to the hexapoles are described in detail. The stability of the synchrotron is demonstrated by measurements in which multiple packets are stored for over 13 s, during which they have completed over 1000 round trips and traveled a distance of over one mile. Furthermore, we demonstrate the simultaneous trapping of 26 packets; 13 revolving clock-wise and 13 counter clock-wise, that are injected into the synchrotron by two Stark decelerator beamlines. We discuss the opportunities for using the synchrotron as a low-energy collider.

Zeitschrift für Physikalische ChemieJan 1, 20136 citations

\mathrm{N}{\mathrm{D}}_{3}

molecules is stably confined in the synchrotron as its injection velocity is continuously scanned from

60\phantom{\rule{0.3em}{0ex}}\mathrm{m}∕\mathrm{s}

$({E}_{\mathrm{kin}}=3.0\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1})\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}87.5\phantom{\rule{0.3em}{0ex}}\mathrm{m}∕\mathrm{s}$ $({E}_{\mathrm{kin}}=6.4\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1})$.