Unblinding the most precise W mass measurement today December 14, 2006Posted by dorigo in news, physics, science.
Today, at 3.30PM Chicago time, CDF will make public its measurement of the W boson mass, which has a total uncertainty of 48 MeV (a 0.06% of the value) and is therefore the most precise single determination of this fundamental parameter of the standard model. I will post the number here as soon as it is broadcast. Stay tuned!
As for the significance of a low or high measurement with respect to the current world average (80392+-29 MeV), I will speak about it in the next post, where I intend to answer a long list of questions by a reader who left a comment in https://dorigo.wordpress.com/2006/12/13/more-speculations-on-non-175-gev-single-top-from-d0-data/ .
For the time being, suffices to say that the probability that the CDF result is lower than the world average is 155/200, since the preliminary (blind) measurement is 80336 MeV with a blind offset of +-100 MeV, and the blind offset has of course a flat probability distribution, 155/200 of which lies below 80392 MeV.