Patent ID: 7807973
Filing Date: 2010-10-05
Classification: G01T

Abstract:
1. A method of detecting a pileup from an output signal of a preamplifier of an energy-dispersive radiation spectrometry system, wherein a filter of said energy-dispersive radiation spectrometry system generates a first pulse in response to said output signal, said energy-dispersive radiation spectrometry system having one or more fast channels, wherein each of said fast channels has an associated energy of full efficiency that depends on a threshold energy associated with the fast channel wherein substantially all photons received by said energy-dispersive radiation spectrometry system having at least said associated energy of full efficiency are detected by the fast channel, the method comprising: measuring an above threshold time duration, said above threshold time duration being a time during which said first pulse is above a minimum detectable threshold energy of said filter; determining that at least one of said one or more fast channels has not made any detections while said first pulse is above said minimum detectable threshold energy of said filter; in response to said determining, declaring a pileup if said above threshold time duration exceeds a longest expected pulse duration, said longest expected pulse duration being a duration of a second pulse that would be output by said filter in response to a single photon being received by said energy-dispersive radiation spectrometry system, wherein said single photon has an energy equal to the associated energy of full efficiency of the particular one of the one or more fast channels which have not made any detections that has the lowest threshold energy.