Physicists at CERN say new data crunching indicates the LHC discovery last July is almost certainly a Higgs boson, though there’s still some mystery as to which kind of the previously-theoretical particle it might be. The ATLAS and CMS teams manning the Large Hadron Collider (LHC) have worked their way through 2.5x the data that was possible for the Higgs boson announcement last year, they said this week, and that initial confidence looks to have been prescient. “The preliminary results with the full 2012 data set are magnificent and to me it is clear that we are dealing with a Higgs boson” CMS spokesperson Joe Incandela said of the latest findings.
However, there’s still work to be done, and the Higgs still has some mysteries to be unlocked. “We still have a long way to go to know what kind of Higgs boson it is” Incandela concedes, with the identification process to be followed by a measurement one.
That second stage is already underway, in fact. “The beautiful new results represent a huge effort by many dedicated people. They point to the new particle having the spin-parity of a Higgs boson as in the Standard Model” ATLAS spokesperson Dave Charlton said. “We are now well started on the measurement programme in the Higgs sector.”
CERN made headlines last year when it announced that evidence from the LHC indicated what had previously been only a theoretical particle had been identified in real life. To do that, the LHC had been systematically smashing particles together and examining the results:
“Whether or not it is a Higgs boson is demonstrated by how it interacts with other particles, and its quantum properties. For example, a Higgs boson is postulated to have no spin, and in the Standard Model its parity – a measure of how its mirror image behaves – should be positive. CMS and ATLAS have compared a number of options for the spin-parity of this particle, and these all prefer no spin and positive parity. This, coupled with the measured interactions of the new particle with other particles, strongly indicates that it is a Higgs boson” CERN
Actual LHC testing won’t resume for some time, however, with the system currently down for maintenance. That’s not expected to be completed until 2015, though the CMS and ATLAS teams say they’ve a backlog of data to work through which should keep them going until more collisions can be run.