The effect of vacuum system time constants on thermal desorption spectra

A numerical analysis of the pressure time equation relating to first order single-step gas release has been performed. This has been done for two configurations of vacuum system, each having a volume into which gas release proceeds linked by a conductance C to a detector volume. The differences between the release function and the observed pressure transient have been characterized by observing the manner in which the maximum release rate ρm, the temperature for maximum release Tm and the leading and trailing 1/e widths We1 and We2 change as a function of the various vacuum system parameters.