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new probabilistic method places higgs boson at higher energy level

“ The new technique took a probabilistic approach to the measurements gleaned from the Fermilab collider. When the accelerator smashes a quark and an anti-quark together, a top quark and an anti-top quark are occasionally created. These quickly decay into other particle types, which themselves decay into yet more particles before the Fermilab detectors can begin to study them. This means the researchers have to work backward, looking at the third generation particles and inferring how they were made back in time, much like looking at a scattering of pool balls and deducing where they were three moves ago. Traditionally, researchers would assign a mass to the initial top and anti-top quarks and figure out what the decayed results should look like, then compare those results with what the detectors actually saw. The new technique works similarly, but assigns probabilities to a range of initial masses, giving more importance to the most accurate readings. The result, when played out over many collisions, is a measurement that’s much more precise.”

“ When the real-world data was parsed, the method yielded a nearly 40 percent increase in precision; less than predicted, but still a tremendous boon to physicists. The improved method allows researchers to glean as much information from the available data as would have been possible from a sample two and a half times as large, which is invaluable when collecting data from each collision is such an delicate and arduous task.

“The second major fallout from the new measurements is that the Higgs boson - the particle that is theorized to give rise to mass itself - apparently exists at higher energy levels than where scientists have been searching. Since all subatomic particles are related to each other, changes in the characteristics of one ripples through other particles, and since the top quark is especially massive, changes to it result in the largest changes in other particles - especially the Higgs. Based on the old accepted value of the top quark mass, physicists expected to find the Higgs boson at around 96 GeV/c2 (gigaelectron-volts), but have been able to rule out that it actually exists there. That threw the whole Standard Model into a quandary. The new measurement for the top quark mass, however, now places the Higgs at about 117 GeV/c2, which is a range accelerators haven’t yet searched, putting the elusive Higgs back into play.”


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