Publications de Benjamin Bertsche

Dynamics of gas phase Ne* + NH3 and Ne* + ND3 Penning ionisation at low temperatures

Andreas Osterwalder, Justinas Jankunas, Benjamin Bertsche

Two isotopic chemical reactions, Ne* + NH_3, and Ne* + ND_3, have been studied at low collision energies by means of a merged beams technique. Partial cross sections have been recorded for the two reactive channels, namely, Ne* + NH_3 → Ne + NH^+_3 + e −, ...

American Institute of Physics2014

Low-temperature Collisions between Neutral Molecules in Merged Molecular Beams

Andreas Osterwalder, Justinas Jankunas, Benjamin Bertsche

We have developed an experiment for the investigation of neutral molecular collisions in the gas phase at temperatures as low as 100 mK. These low temperatures are obtained by merging two supersonic expansions, using an electric and a magnetic guide, and b ...

Schweizerische Chemische Gesellschaft2014

Low Energy Collisions in Merged Neutral Molecular Beams

Benjamin Bertsche

Within this thesis two experiments will be described. In the first experiment a velocity filter was used to obtain a beam of polar molecules (ND3) with a translational temperature of less than 5K. For the first time the dynamics of individual rotational st ...

EPFL2014

Study of the Ne(3P2) + CH3F Electron-Transfer Reaction below 1 K

Andreas Osterwalder, Justinas Jankunas, Benjamin Bertsche

Relatively little is known about the dynamics of electron-transfer reactions at low collision energy. We present a study of Penning ionization of ground-state methyl fluoride molecules by electronically excited neon atoms in the 13 μeV–4.8 meV (150 mK–56 K ...

Amer Chemical Soc2014

Preparation of Translationally Cold Neutral Molecules

Andreas Osterwalder, Giulia Di Domenicantonio, Benjamin Bertsche

Efforts at EPFL to obtain translationally cold neutral molecules are described. Active deceleration of polar molecules is performed by confining the molecules in moving three-dimensional electrostatic traps, and by appropriately choosing the velocity of th ...

2011

Dynamics of individual rotational states in an electrostatic guide for neutral molecules

Andreas Osterwalder, Benjamin Bertsche

The guiding properties of individual rotational states of deuterated ammonia inside an electrostatic hexapole guide are presented. The guide is combined with resonance enhanced multiphoton ionization detection to assess the guiding probabilities and veloci ...

2011

State-selective detection of velocity-filtered ND3 molecules

Andreas Osterwalder, Benjamin Bertsche

Translationally cold and slow ND3 is prepared by filtering the slow molecules from a thermal gas-phase sample using a curved electrostatic hexapole guide. This filter, like the curved quadrupole guide introduced by Rangwala et al. Phys. Rev. A 67 043406 (2 ...

2010