The new data allowed physicists to make the most accurate measurement of the mass of the W-boson.
After a decade of analysis, physicists have been able to measure the mass of the W boson most accurately, which could change physics as we know it. According to the authors, their measurement is very different from predictions based on the Standard Model.
The Standard Model of particle physics was developed in the 1970s: it explains how particles interact and fundamental forces work. It doesn’t cover everything – it doesn’t explain dark matter or even gravity. But now the authors of the new work have studied the W-boson well and want to revise the General Model.
The mass of a particle can be calculated through its ratio with other particles in the Standard Model. Further, this predicted mass can be compared with the actual measurements that were made in the collider. It turned out that both values diverge greatly, in the case of the W-boson.
W-bosons are elementary particles that carry a weak force and affect nuclear processes, such as those that occur in the Sun. According to the Standard Model, their mass is related to the mass of the Higgs boson and the mass of a subatomic particle, the top quark.
In a new study, almost 400 scientists in collaboration with Fermilab (CDF) have been studying 4.2 million potential W-boson candidates for a decade. They were searched based on data for 26 years of operation of the Tevatron collider. As a result, the team was able to calculate the mass of the W boson to within 0.01%.
According to their calculations, the W boson has a mass of 80,433.5 megaelectronvolts (MeV) with an uncertainty of only ±9.4 MeV. This is within the range of some previous measurements, but well above the predictions from the Standard Model. According to it, the mass is 80 357 MeV, ± 6 MeV.