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International Journal of Modern Physics A

MANY SUCCESSIVE MEASUREMENTS AND EXPONENTIAL DECAY

K. Urbanowski

Published Mar 10, 1991• 11 citations
Publisher

Abstract

A multiple repeated measurement of the unstable state evolving in time is discussed. We show that there is no decay in the limit of continuous measurements and there is a purely exponential decay law in other cases. We also give formulae for the effective decay width in the cases of very short, intermediate, relatively long and very long time intervals separating successive measurements. Our results are compared with the Weisskopf-Wigner formula for weak decays. Based on our model of a measurement, we show that the decay width does not depend on properties of the real detectors in practice.

DOI
10.1142/s0217751x91000587

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