Abstract Positron emission tomography (PET) systems employ mixed-signal front-end to carry out relatively simple, and ad hoc , processing of the charge pulses generated upon event detection. To obtain, and maintain over time, proper calibrations of the mixed-signal circuitry for generating accurate event information is a challenging task due to the simplicity of the event processing, and the huge number of channels and multiplexing of the input signals found in modern PET systems. It is also difficult to modify or extend the event-processing technologies when needs arise because it would involve making changes to the circuitry. These limitations can be
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A Multi-threshold Sampling Method for TOF-PET Signal Processing
Abstract As an approach to realizing all-digital data acquisition for Positron Emission Tomography (PET), we have previously proposed and studied a multi-threshold sampling method to generate samples of a PET event waveform with respect to a few user-defined amplitudes. In this sampling scheme, one can extract both the energy and timing information for an event. In this paper, we report our prototype implementation of this sampling method and the performance results obtained with this prototype. The prototype consists of two multi-threshold discriminator boards and a time-to-digital converter (TDC) board. Each of the multi-threshold discriminator boards takes one input and provides
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Difference Between Survey Meters, Geiger Counters and Dosimeters
Meters and dosimeters have separate roles in indicating the presence of hazardous radiation levels and are critical life-saving tools in nuclear emergencies. Survey Meters The following instruments measure exposure rate or the intensity of radiation at a location at some point in time: survey meters, field survey meters, rate meters, radiac meters, radiation detection meters, low-range meters, high-range meters, airborne meters, fallout meters, remote monitors, Geiger counters, and even dose rate meters. Like the speedometer of a car shows miles/hr, they all show measurements relative to time, such as R/hr or mR/hr. If you enter a radioactive area and your
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