Simulated results for position dependence of the relative number density of the guided ND<sub>3</sub> molecular beam in the filter with <em>R</em> = 150 mm

<p><strong>Figure 10.</strong> Simulated results for position dependence of the relative number density of the guided ND<sub>3</sub> molecular beam in the filter with <em>R</em> = 150 mm. All data points are normalized to one at the position of = 0°. The right inset shows the relative number density of the packet as a function of the position ranging from = 10° to = 70°.</p> <p><strong>Abstract</strong></p> <p>We propose a scheme of a surface electrostatic velocity filter capable of preparing cold polar molecules on the surface of a substrate by selecting a low-velocity component of an effusive beam from a thermal gas reservoir. Using ND<sub>3</sub> as a molecular sample, the dependence of the performance of the filter on the parameters of both the filter setup and the incident molecular beam is investigated by using a theoretical model and Monte Carlo simulations. A detailed study of the guiding process of molecules, including the evolution of phase space density of the packet in the filter, is carried out and shows that the beam selection process is mainly completed in the front part of the filter.</p>