Scientists at the U.S. Department of Energy's Fermi National Accelerator Laboratory have obtained the world's most precise measurement of the W boson's mass. This has led to a reduction of territory where the Higgs boson could actually exist. The collaboration between the Tevatron, a particle accelerator at FermiLab, and CDF and DZero experiments have determined that the Higgs particle cannot have a mass between 160 and 170 GeV/c2. Dennis Kovar, Associate Director of the Office of Science for High Energy Physics at the U.S. Department of Energy says "We're looking forward to further Tevatron constraints on the Higgs mass." The analysis data from earlier measurements had predicted that the Higgs particle should have a mass between 114 and 185 GeV/C2. FermiLab's results eliminate a significant fraction of Higgs territory and provide stricter bounds on the mass of the Higgs boson.
So what makes the Higgs boson so important? In a single phrase, the Higgs is believed to be a particle, or set of particles that might give others mass. An adapted analogy from CERN is the following; Imagine that a room full of physicists chattering quietly is like space filled with the Higgs field. Suddenly, Einstein walks in, creating a disturbance as he moves across the room and attracting a cluster of admirers. With each step his resistance to movement increases, in other words, he acquires mass, just like a particle moving through the Higgs field. Now picture that a rumor crosses the room. It creates the same kind of clustering, but this time among the scientists themselves. In this analogy, these clusters are the Higgs particles.
The Higgs particle is an important element of the theoretical framework known as the Standard Model. According to the Standard Model, the Higgs boson would be able to explain why some particles have mass and others do not. To increase the chances of of finding the Higgs boson, the CDF and DZero scientists combine their results from separate analysis and create twice the amount of data. The Director of TRIUMF, Nigel Lockyer was co-spokesperson from 2002-2004 for the CDF experiment and helped pave the way for future accomplishments, "During my tenure as co-spokesperson, CDF made the transition from collaboration focused on the detector upgrade to one in which faculty, staff scientists, post-docs, and, most importantly, thesis students focused on extracting the most physics from our data." This experience, among others, widened his knowledge of accelerator physics which is reflected through his leadership at TRIUMF, home to the world's largest cyclotron.
By Maria Jose Crousillat
Communications Assistant
Based on Fermilab's Press Release
http://www.fnal.gov/pub/presspass/press_releases/Higgs-mass-constraints-20090313.html