The new W-mass value leads to an estimate for the mass of the yet-undiscovered Higgs boson that is lighter than previously predicted, in principle making observation of this elusive particle more likely by experiments at the Tevatron particle collider at Fermilab.
Commenting on this finding CDF collaborator Dr Mark Lancaster from University College London said, “This result is very encouraging for Higgs hunters at the Tevatron and the Large Hadron Collider (LHC). It confirms the Higgs is light and now we have to find it. After more than 10 years we are now honing in on the Higgs. Further data from the Tevatron or new data from the LHC in the next 2-3 years should be enough to finally confirm or rule out the existence of the mythical Higgs particle once and for all.”
Scientists working at the Collider Detector at Fermilab measured the mass of the W boson to be 80,413 +/- 48 MeV/c^2, determining the particle’s mass with a precision of 0.06 percent. Calculations based on the Standard Model intricately link the masses of the W boson and the top quark, a particle discovered at Fermilab in 1995, to the mass of the Higgs boson. By measuring the W-boson and top-quark masses with ever greater precision, physicists can restrict the allowable mass range of the Higgs boson, the missing keystone of the Standard Model.
“This new precision determination of the W boson mass by CDF is one of the most challenging and most important measurements from the Tevatron,” said Associate Director for High Energy Physics at DOE’s Office of Science Dr. Robin Staffin. “Together, the W-boson and top-quark masses allow us to triangulate the location of the elusive Higgs boson.”
The CDF result is now the most precise single measurement to date of the W boson mass. Combining the CDF result with other measurements worldwide leads to an average value of the W-boson mass of 80,398 +/- 25 MeV/c^2.
Prior to the announcement of the CDF result, ALEPH, an experiment at CERN, the European Center for Nuclear Research, held the record for the most precise W mass measurement. ALEPH and its three sister experiments at CERN, which operated until 2001, made significant contributions to the measurement of the W’s mass. The experiments relied on electron-positron collisions produced by the LEP collider at CERN. In contrast, CDF experimenters are analyzing proton-antiproton collisions produced by Fermilab’s Tevatron, the world’s most powerful particle collider.
“Compared to the electron-positron collisions at LEP, the proton-antiproton collisions at the Tevatron result in a ‘dirty’ environment experimentally,” said Jacobo Konigsberg, University of Florida physicist and CDF co-spokesperson. “Every collision produces hundreds of particles along with the W boson that need to be properly accounted for. That’s why our analysis is so challenging.”
Now, having gained a much better understanding of their detector and the processes it records, CDF scientists are optimistic that they can further improve the precision of their W-mass result by a factor of two in the next couple of years.
“You have to sweat every detail of the analysis,” said Fermilab physicist and co-spokesperson Robert Roser. “Our scientists cannot take anything for granted in an environment in which composite particles such as protons and antiprotons collide. We need to understand the many different subatomic processes and take into account the capabilities of our detector for identifying the various particles.”
In a talk at Fermilab on Friday, January 5, Ashutosh Kotwal, CDF collaborator and Professor of Physics at Duke University, presented the W-mass result to the scientific community. The result will be submitted in a paper to Physical Review Letters.
This W mass measurement is yet another major result of Tevatron Run II announced by scientists in the last year, indicating the progress that experimenters have made with both the CDF and the DZero experiments at Fermilab. As the two collaborations continue to take data, collaborators press the search for the Higgs boson as well as for signs of dark matter particles and extra dimensions.
"The CDF and DZero experiments have much more data to analyze, and they are observing more and more collisions at a faster and faster rate,” said Fermilab Director Pier Oddone. “Our experimenters are now in a position to look for some of the rarest and most amazing phenomena that theorists have predicted, as well as to find the completely unexpected. This is a very exciting time."
Gill Ormrod | alfa
Taking a spin on plasma space tornadoes with NASA observations
20.11.2017 | NASA/Goddard Space Flight Center
NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
20.11.2017 | Earth Sciences
20.11.2017 | Earth Sciences
20.11.2017 | Life Sciences