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Medical Term:

time of flight


the time for a photon created by annihilation of a positron-electron pair to reach a detector; because annihilation photons are created in pairs and travel in opposite directions at about 3 × 1010 cm/sec, measurement of the difference in arrival time at detectors with subnanosecond resolution allows calculation of the location of the event; the basic physics of positron emission tomography.

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.