  Mass spectrometry is used in a wide range of scientific disciplines including
proteomics, pharmaceutics, forensics, and fundamental physics and chemistry.
Given this ubiquity, there is a worldwide effort to improve the efficiency and
resolution of mass spectrometers. However, the performance of all techniques is
ultimately limited by the initial phase-space distribution of the molecules
being analyzed. Here, we dramatically reduce the width of this initial
phase-space distribution by sympathetically cooling the input molecules with
laser-cooled, co-trapped atomic ions, improving both the mass resolution and
detection efficiency of a time-of-flight mass spectrometer by over an order of
magnitude. Detailed molecular dynamics simulations verify the technique and aid
with evaluating its effectiveness. Our technique appears to be applicable to
other types of mass spectrometers.

Atomic Physics;Chemical Physics