Pulsed molecular‐beam sources

A new type of fast, pulsed molecular‐beam source for collision studies and molecular spectroscopy appears to have several advantages over the traditional continuous‐flow sources. It improves signal‐to‐noise in the detectors, produces very “cold” beams with little or no rotational or vibrational excitation, and it allows good time‐of‐flight measurements to determine velocity spectra. The source was developed by W. Ronald Gentry and Clayton Giese at the University of Minnesota. Their work employs two such sources to investigate collisions between two molecular beams.