Matt Strassler took some time last week to note at his blog that the CDF recalculation of the W boson mass (which was 0.1% higher than other measurements and also much higher than the Standard Model prediction from other known physical constants, which seems modest but is a little more than eight standard deviations higher than the expected value) was wrong.
The Standard Model electroweak fit from other physically measured constants (shown as the dashed line in the chart below) is as follows:
80,357 ± 4 [inputs] ± 4 [theory] MeV/c2
Since the ATLAS and CMS results are both consistent with all other previous measurements as well as with the Standard Model, and since CMS has even reached the same level of uncertainty obtained by CDF, this makes CDF by far the outlier, as you can see above. The tentative but reasonable conclusion is that the CDF measurement is not correct.
This was pretty much what everyone had suspected in April of 2022 when this CDF result was announced. The source of the error in the CDF measurement and reanalysis of data is still not entirely clear.
A Particle Data Group review article on the subject is here. The PDG world average doesn't yet include the 2024 experimental results.
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