Simulated results of position dependence of the transverse temperature (a) and the longitudinal temperature (b) of the guided packet in the filter with different radii <em>R</em> of curvature

<p><strong>Figure 9.</strong> Simulated results of position dependence of the transverse temperature (a) and the longitudinal temperature (b) of the guided packet in the filter with different radii <em>R</em> of curvature. The right insets show a close-up of the transverse temperature in the relevant region (a), or an overview of the longitudinal temperature for the case of <em>R</em> = 50 mm (b).</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>