News at a glance: A particle ’s weighty measurement, Marburg in Africa, and a fossil called “the blob”

PARTICLE PHYSICS Particle mass dispels hint of new physics A fleeting, weighty elementary particle called the W boson has just the mass predicted by theory, physicists working with Europe’s Large Hadron Collider (LHC) reported this week at a conference in Italy. The finding comes from ATLAS, one of four large particle detectors fed by the LHC, and it contradicts the eyebrow-raising measurement reported last year in Science that suggested the W was heavier than predicted by physicists’ prevailing standard model . That discrepancy could have signaled that massive new particles lurking in the vacuum alter the mass of the W, which conveys the weak nuclear force just as the photon conveys electromagnetism’s force. The hint that the W boson might be extra-hefty came from an analysis of data from a particle detector called D0, which was fed by the now-defunct Tevatron collider at the Fermi National Accelerator Laboratory. The analysis disagreed not only with the standard model, but also with D0’s previous measurement. Now it is even more of an outlier. EPIDEMIOLOGY Marburg cases widen in Africa Public health experts are combating two outbreaks of the deadly Marburg virus on opposite sides of the African continent. Authorities in Equatorial Guinea have reported nine confirmed and 20 probable cases of the hemorrhagic fever since early January; 27 of the 29 patients have died. The cases a...
Source: ScienceNOW - Category: Science Source Type: news