In a talk at the ongoing Rencontres de Moriond conference, the ATLAS collaboration presented the result of its latest test of a key principle of the Standard Model of particle physics known as lepton flavour universality. The precision of the result is the best yet achieved by a single experiment in decays of the W boson and surpasses that of the current experimental average. Most elementary particles can be classed into groups or families with similar properties. For example, the lepton family includes the electron, which forms the negatively charged cloud of particles surrounding the nucleus in every atom, the muon, a heavier particle found in cosmic rays, and the tau-lepton, an even heavier short-lived particle only seen in high-energy particle interactions. As far as physicists know, the only difference between these particles is their mass, as generated through their different strengths of interaction with the fundamental field associated with the Higgs boson. In particular, a rem
Examining the delicate balance of lepton flavors phys.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from phys.org Daily Mail and Mail on Sunday newspapers.
".even if we don't understand each other, that's not a reason to reject each other. There are two sides to any argument. Is there one point of view that has all the answers? Give it some thought." -Alder, from Pokémon
“What might we learn from lines of research that are off the beaten track? They check accepted ideas, always a Good Thing, and there is the chance Nature has prepared yet another surprise for us.” -Jim Peebles
It's been a huge week here at Starts With A Bang, and one of our busiest on record. If you thought that Pluto's demotion was the biggest news about the outer Solar System, just wait until you get to the highlight of this week: