Measurement of Vacuum Pressure with a Magneto-Optical Trap: a Pressure-Rise Method

The lifetime of an atom trap is often limited by the presence of residual background gases in the vacuum chamber. This leads to the lifetime being inversely proportional to the pressure. Here we use this dependence to estimate the pressure and to obtain pressure rate-of-rise curves, which are commonly used in vacuum science to evaluate the performance of a system. We observe different rates of pressure increase in response to different levels of outgassing in our system. Therefore we suggest that this is a sensitive method which will be useful in applications of cold atom systems, in particular where the inclusion of a standard vacuum gauge is impractical.