3 τ lifetime

A total of 6 τ lifetime measurements are averaged. All are included in the 2022 edition and 2023 update of the Review of Particle Physics [8]. The fit has χ²/d.o.f. = 1.87/5, corresponding to a confidence level CL = 87%. Table 2 and Figure 2 report the experimental inputs and the calculated average, which are also available at [9].

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Table 2: τ lifetime measurements and their average.

τ lifetime [fs]	Experiment	Reference
290.10 ± 1.50 ± 1.10	ALEPH	[18]
290.17 ± 0.53 ± 0.33	Belle	[19]
289.00 ± 2.80 ± 4.00	CLEO	[20]
290.90 ± 1.40 ± 1.00	DELPHI	[21]
293.20 ± 2.00 ± 1.50	L3	[22]
289.20 ± 1.70 ± 1.20	OPAL	[23]
290.29 ± 0.53	HFLAV average

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PNG format	PDF format

Figure 2: τ lifetime measurements and their average.

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