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A Measurement of the K_S Lifetime

NA48 Collaboration
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Abstract

A measurement of the K_S lifetime is presented using data recorded by the NA48 experiment at the CERN-SPS during 1998 and 1999. The K_S lifetime is derived from the ratio of decay time distributions in simultaneous, collinear K_S and K_L beams, giving a result which is approximately independent of the detector acceptance and with reduced systematic errors. The result obtained is tau_S=(0.89598 +- 0.00048 +- 0.00051)x10^(-10) s, where the first error is statistical and the second systematic.

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NA48 Collaboration. 2002-05-04. A Measurement of the K_S Lifetime. https://doi.org/10.1016/s0370-2693(02)01837-3

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